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Alaska Airlines flight forced to make an emergency landing...
82

Alaska Airlines flight forced to make an emergency landing...

Alaska Airlines flight forced to make an emergency landing...

(OP)
This was a close call...

Alaska Airlines Flight Makes Emergency Landing After Window Blows Out Mid-Air

A photo sent to Oregon's KATU-TV shows a gaping hole in the side of the airplane next to passenger seats.


https://www.huffpost.com/entry/alaska-airlines-eme...

An excerpt from the above item:

An Alaska Airlines flight made an emergency landing in Oregon on Friday after a window and chunk of its fuselage blew out in mid-air, media reports said.

A passenger sent KATU-TV a photo showing a gaping hole in the side of the airplane next to passenger seats. It was not immediately clear if anyone was injured.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

From PPRuNe, apparently the panel that blew out is typically an emergency exit though Alaskan doesn't require it so it's plugged. I guess that didn't work well.

RE: Alaska Airlines flight forced to make an emergency landing...

It was an optional emergency exit that the airline chose not to fully outfit. The door left the airplane and the interior cover to conceal it went with it. I expect affected planes will already be scheduled to be out of service to check that door ahead of the FAA telling them to do so.

RE: Alaska Airlines flight forced to make an emergency landing...

Really big hole. Very lucky no one or a flight attendant didn't get sucked out.

Keep your seatbelt on at all times!

https://www.bbc.co.uk/news/world-us-canada-6789956...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

davidbeach in thread thread815-515237: Boeing again posted this link:
The Oregonian

According to the article, the 737-9 was new - just 2 months old. Brings up the questions. Had that door been properly latched/secured before the interior panel was placed over it? Or, is it some other kind of failure?

RE: Alaska Airlines flight forced to make an emergency landing...

The door is appently normally hinged at the bottom and secured with lugs and an opening mechanism.

If not used the door is still there and just sealed closed and then covered on the inside like any other seat.

Going to be really interesting to see what comes from this.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

it will be a production quality issue.

They are already having to check certain bolts world wide which apparently are not installed properly.

RE: Alaska Airlines flight forced to make an emergency landing...

and from the BBC... Boeing is looking into... I feel safer already. As I noted earlier, I'm glad it was only at 16,000 feet. This was a lucky outcome; at 50,000 37,000 feet, it could have been a little different.

"The Alaska Airlines Boeing 737 Max 9 turned back minutes into its flight to California after an outer section, including a window, fell off on Friday.

There were 177 passengers and crew on board and it landed safely in Portland.

The airline said it would temporarily ground all 65 of its 737 Max 9 aircraft to conduct inspections.

Boeing said it was aware of the incident and was "working to gather more information"."

https://www.bbc.com/news/world-us-canada-67899564

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I can't see them having a plug door in there without hinges and covered up...

Those things are heavy.

RE: Alaska Airlines flight forced to make an emergency landing...

Can a 737 even get to 50,000 feet?

RE: Alaska Airlines flight forced to make an emergency landing...

Tugboat .... This source indicates that max altitude for Boeing 737s is 41,000 ft ...

Optimal altiude for economy is around 37,000 ft

https://www.sheffield.com/2022/what-is-cruising-al....

MJCronin
Sr. Process Engineer

RE: Alaska Airlines flight forced to make an emergency landing...

Not with pax on board.

Think they used to be 37k and the NG 41k.

This is a certification limit. They can go higher depending on the temperature and a few other variables.

Biz jets go up to 50k it's one there selling points above everything else so they can go direct.

Think the old 747 types went higher but the radiation dose goes through the roof.

RE: Alaska Airlines flight forced to make an emergency landing...

It's not a plug door apparently.

But looking closer it seems the ENTIRE door frame fell off. Below is apparently one of these doors before being covered up. See the two lugs on the top.

Then look at what was left.

So it looks very bad if the whole door frame decided to part company.






Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Everything that is permanently attached to the aircraft remained attached. The door pulls in slightly and then slides up to un-align the pins before hinging outward in normal operation.

RE: Alaska Airlines flight forced to make an emergency landing...

3D Dave.

Look closer. The door frame is missing.

All max 9s now grounded in the US.

Now it might have just been ripped out after the door opened and got ripped off in the wind, but it's not just the door which has gone as far as I can see.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Can a 737 even get to 50,000 feet?)


my error... didn't know that. When I've been flying that altitude is about 50,000... I guess not 737s.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Littleinch,

The frame you are looking at is part of the door.

RE: Alaska Airlines flight forced to make an emergency landing...

It looks as if Boing is still suffering with too much MBA oversight on engineering and quality control.
Is the 737 Max becoming the Corvair of the sky?

Quote (Ralph Nader)

Unsafe at any speed!

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Fair enough 3D,

Its the colour that got me.

Still don't understand how it can just pop off though...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

I used to have a Corsair Corsa... it was a really neat car... once you got use to handling it, there was no issue... not a lot different than the Volkswagen or the Porsch 911... the 911 had the handling worked out a little better.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

3DD... excellent clip

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Ralph Nader was wrong :)

The problem with sloppy work is that the supply FAR EXCEEDS the demand

RE: Alaska Airlines flight forced to make an emergency landing...

concur

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

The Corvair and Pinto got all the bad publicity, mostly undeserved. The 737 MAX is definitely deserving of bad publicity. Boeing as a whole really seems to have lost it's way.

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

Its not a production QA problem, Now it's a corporate cultural issue.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

I'd be very interested to see the plug on the opposite side of the plane.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

Its not a production QA problem, Now it's a corporate cultural issue.
Or a corporate cultural problem lading to production QA problems,
Either way,

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

The culture problem started with McD buying Boeing in 1997.

RE: Alaska Airlines flight forced to make an emergency landing...

The saying is that McDonell Douglas bought Boeing with Boeing's money.

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

And wasn't that because McD was going down the tubes partly as a result of their culture problem?
If a culture disrespects engineers, eventually they will no longer have the top tier of engineering talent available.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

I thought that that was;
Boing bought McD with McD's money.

But think about it;
A door blowing out in flight.
That must have been incredibly distracting.
Something like that could result in the pilots forgetting to turn off the anti-icing heaters.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)

Quote (thebard3)


The saying is that McDonell Douglas bought Boeing with Boeing's money.

While this all happened six years after MDC sold our division to EDS, this isn't how we heard it from our old workmates, although in the end, the new Boeing logo did bare an amazing resemblance to the old McDonnell Douglas logo:





Prior to the 1997 acquisition of MDC by Boeing, the Boeing logo consisted of just the word 'Boeing'.

And for the record, I'm drawing a monthly pension from Boeing, a company I never worked for. But then, I'm also drawing a monthly pension from HP, another company I never worked for.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

https://www.youtube.com/shorts/K6hephOelG0?feature...

The way the large doors have to move inside first before the door opens has always made me confident. A plug of this size that depends on just bolts may not be as failsafe.

Why did this plug popout? Who at Boeing is feeling queasy right now?

RE: Alaska Airlines flight forced to make an emergency landing...

I am not sure there would have been the door + frame sitting there covered up.

They want to keep the weight down. Those doors weight plus frame must be around 200kg each. Your not going to fly around nearly a ton of extra metal which does nothing. Apart from anything else it decreases the traffic load by having a higher basic mass plus increases the fuel burn. A220 fuel burn increases by 60kg per 1000kg of weight per hour. That's why its an option which only high capacity airline's go for to be able to get more seats shoe horned in. An extra 50kg per hour doesn't sound much but when the thing is in the sky 12 hours a day that's 600kg. That's 219 tons of fuel per year at 700$ per metric ton. So basically 1.5 million over 10 years.

There are also no rivet holes on the skin round the hole plus no damage to the surrounding skin.

I have zero clue what they might have put instead in that failed. Just don't think it will be what's depicted in the picture. I am quiet happy to be wrong though.

Note the calculation above is done with me thinking there are 4 of these unused. If its only two of them divide by 2.

RE: Alaska Airlines flight forced to make an emergency landing...

Going by the following video (already posted by 3DDave above), the bolts do not hold the non-door plug against pressurisation. It looks to me like the non-door plug is essentially the same structure as a door, but with all of the extra bits removed (i.e. the opening handle and mechanism, pressure equalisation vent, slide, etc), and a full size window instead of the smaller port hole.

737 Mid-Cabin Emergency Exit Doors

As I interpret it, the plug slides downwards (the same as a door, if fitted) behind "stop fittings", and the bolts just prevent it from sliding up again. The air pressure pushes the structural fittings on the plug or door against the structural fittings on the frame, and the bolts should only have minimal stress on them (relative to the in-service maximum of around 8psi (I'm not certain of the max delta on the 737 MAX, but it should be around that) multiplied by the door area from pressurisation). I'm not saying the frame is exactly the same frame used if a door is fitted (it may or may not be), only that the mechanism that resists the pressure looks to be essentially the same.

Purely speculatively, I'm wondering if someone either forgot to fit the bolts, or used insufficient torque or Loctite on them.

RE: Alaska Airlines flight forced to make an emergency landing...

Anyone who hasn't done so - watch the video I posted a link to. The weirdness of the speculations is freaking me out.

Yes, some airlines opted to put an emergency exit door, but inoperative, in place. Others went with a plug door. The inop door means they can reconfigure the seating and interior panel without having to recertify the plane. The plug door means they believe they will never recertify or are willing to eat the cost.

JRS87 - the second video you linked to - that's a different situation caused by a passenger. The plug door that escaped uses the same plug features as Airbus does on all their main doors. The bolts that are installed on the escaped door were supposed to keep the door from moving up to unalign the capture fingers around the door. The features that keep the door from moving outward are the capture fingers, again, the same as Airbus uses on their main doors.

The fasteners are to have castellated nuts and cotter pins. Even without that there is a spring load to supply some friction.

One mystery for me now is that the door has to come in before it can move up, so how was that possible with the plane pressurized? If all the bolts had fallen out (just being loose would not allow movement) then why did this not happen during the taxi process with much vibration and no pressure? There are retaining straps that hold the door from fully opening, so if the door popped open during taxi they would not have been able to pressurize the plane. Or, maybe, that is what happened and the interior cover is what kept the pressure in up until it could not do so any longer and the failed interior cover pushed against the open door and broke the retaining straps.

A passenger could have noticed the wall of the plane was no longer where it should be, but we'll see if that comes out. They may not have realized what it meant or no one was paying attention. The seat next to the panel was unoccupied, so no one would be leaning against it to feel it move. They could also have seen the window was 5-6 inches farther out than all the other windows and not aligned with the interior trim opening by the 1.5 inch vertical movement to release it.

Additionally perplexing is they had pressurization issues reported, but if the door hasn't moved in then why was the door seal not functioning correctly?

I can picture that the door has been loose for a while, the bolts all out, and the door lift spring pushing up and allowing the seal to open just a tiny amount. Then, when pressure is applied the door pushes back and down, sealing correctly. But if the interior panel has been preventing the door from moving fully up in the past, then why did that happen this time?

RE: Alaska Airlines flight forced to make an emergency landing...

Do you know what the weight penalty is between the two?

RE: Alaska Airlines flight forced to make an emergency landing...

Is the strap assembly left in place on these plug doors or is it only installed during maintenance operations?

RE: Alaska Airlines flight forced to make an emergency landing...


Comparing theses two photos, did the door leave by itself or did the door and the door frame leave together?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

You can see the "stop fittings" or fingers sticking out from the frame, and it all looks reasonably intact and normal. It appears that the plug was able to open normally, by first moving upwards to disengage from the frame, then hinging out from the bottom.

RE: Alaska Airlines flight forced to make an emergency landing...

more...

"Thousands of passengers face flight cancellations after major US airlines grounded dozens of Boeing jets after a mid-flight blowout over Oregon.

The US aviation regulator said 171 Boeing 737 Max 9s must be grounded for checks after part of an Alaska Airlines plane's fuselage fell off on Friday.

Alaska said flight disruptions are expected to last into next week. United Airlines has grounded 79 planes.
Disruptions are likely to primarily affect flights in the US.

It follows regulator the Federal Aviation Administration (FAA) ordering "immediate inspections" of 737 Max 9s worldwide."

https://www.bbc.com/news/world-us-canada-67905336

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

3DD -
re: Yes, some airlines opted to put an emergency exit door, but inoperative, in place. Others went with a plug door. The inop door means they can reconfigure the seating and interior panel without having to recertify the plane. The plug door means they believe they will never recertify or are willing to eat the cost.
Boeing has certified all of the configurations, operable door, inop door, plug door, both structurally and for egress vs number of seats; an airline will not need to "recertify". There probably is not a production option to not install any type of door on the -9. An inop door is heavier than a plug door. So an airline which thinks they will never use the door will opt for a plug door to reduce weight and have a standard window. But when they eventually sell the aircraft the new operator may want to install a operating door if they are in a high dense seating arrangement.

The door came cleanly off, there is no sign at all of any damage to the basic fuselage structure. Which as you said is very strange. This plane has been flying since October. Hard to imagine the retaining fasteners coming loose and falling out to allow the door to slide upwards. Perhaps the fasteners were never installed. Hopefully the NTSB/FAA can figure it out.

Also wonder if there is a difference between the -900 (NG) and -9 (Max) door designs.


RE: Alaska Airlines flight forced to make an emergency landing...

Love the expression "fell off"

If you want I can get some close up pics of the door retention mechanism on the a220

RE: Alaska Airlines flight forced to make an emergency landing...

I just realised this, "The impact of this was reduced by two key factors. First of all, the passengers would all have been wearing seatbelts at this stage in the flight, keeping them in their seats."

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Alistair - I know how operative doors are latched and retained. Just have never seen how the plug "doors" are fastened in. You wouldn't be able to get access to an A220 plug door even if that a/c had one, which I don't think it does, as the interior panels cover it.

RE: Alaska Airlines flight forced to make an emergency landing...

A relatively new plane... maybe covered by warranty?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Excellent video. Thanks for posting the link.

Seems likely that the four retaining bolts were somehow not installed at some point in the production process.

RE: Alaska Airlines flight forced to make an emergency landing...

Only flying since 11/11/23 per multiple reports.

When one this sentence into the German to translate wanted, would one the fact exploit, that the word order and the punctuation already with the German conventions agree.

-- Douglas Hofstadter, Jan 1982

RE: Alaska Airlines flight forced to make an emergency landing...

It would be the best possible lucky strike imaginable for Boeing if those bolts were left out and neither were there any serious injuries, or no injuries at all, and also that there is minimal damage to the airframe.

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

We don't have them.

But I know lads in the heavy maintenance hanger doing the C checks who would get them if we did.

I suspect it will be the same as the emergency exit otherwise it would carry a hefty certification penalty.

RE: Alaska Airlines flight forced to make an emergency landing...

The door goes down to open, not up.
CORRECTION
The door goes up to open

Quote (3ddAVE)

Chris Brady misspoke. The springs push the door up. The pins are on the door frame and the groove is on the door.
There are springs to hold the door up into the latches.
With the four blocking bolts missing, vibration may have worked the door down until it cleared the latches.
It looks like Boing's MBA driven management still hasn't got their Quality Control together yet.
After rechecking, I agree Dave.


And then there are the airline MBAs who ignored Boing's deteriorating culture and bought the MAX in anticipation of saving a few bucks.
I wonder if their anticipated savings were more than the lost revenue from this grounding.
Gotta love those MBAs.
The lawyers are going to get rich suing Boing for lost revenue.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

I am guessing that the door is about 2000 square inches.
So for every 1 PSIG delta pressure there will be a ton force on the door.
No wonder it came off cleanly.
Has the door been found or did it part company over the ocean?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

It was tracked on primary radar into a Portland neighborhood, but I see no reports of the recovery. There is a river, so that complicates things.

RE: Alaska Airlines flight forced to make an emergency landing...

Chris Brady misspoke. The springs push the door up. The pins are on the door frame and the groove is on the door.

RE: Alaska Airlines flight forced to make an emergency landing...

There are videos after the incident. The flight looks fairly full. It seems odd that nobody was seated by the door. Perhaps there was a warning sign and the people were moved? It seems like it was fairly violent when it failed. The pictures posted here show the upholstery and padding were sucked off of a seat frame.

RE: Alaska Airlines flight forced to make an emergency landing...

"Bob" found the plug in his back yard in Portland. That should, hopefully, allow them to confirm if it was a case of missing bolts or something else (i.e. if the fittings are all still present and reasonably normal on the plug, and the frame looks normal, it really can only be a case of missing bolts).

NTSB Media Brief - Alaska Airlines Flight 1282 (Jan 7) livestream *UPDATE*

RE: Alaska Airlines flight forced to make an emergency landing...

She sounds like she is very qualified and will get to the bottom of this.

RE: Alaska Airlines flight forced to make an emergency landing...

She's an administrator (currently NTSB Chair), rather than someone with a science and engineering background. She has been with the NTSB since 2018, seems to have bi-partisan support in Congress, and she's publicly called out Musk as the con man that he is (regarding "full self driving").

RE: Alaska Airlines flight forced to make an emergency landing...

the interesting point on those videos of the brief was it was an ETOPS machine. Engines Turning or Pax Swimming as its unofficially an acronym for. Official extended twin operations for more than 60 mins from a diversion airfield.

And they were on about the infant carriage requirements. None FAA we have them strapped to the parent. using a secondary lap belt. And using car seats in the cabin is problematic.

RE: Alaska Airlines flight forced to make an emergency landing...

Tug, I saw on another website, maybe Pprune, that the passengers supposed to be sitting there missed their connection. Quite possibly saved their lives. Even with seatbelt signs still on, many don't really tighten them and lap belts may not stop you getting "extracted", especially that window seat.

But there are now reports that the plane had "pressurisation issues" 3 or 4 times recently and Alaska decided not to fly that plane over water for extended periods.

Seems remarkable that the plug was only restrained in movement by 4 bolts that are difficult to check without removing the internal covers.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

I presume those bolts were meant to be subject to lockwire and a dupe sign off after installation.

RE: Alaska Airlines flight forced to make an emergency landing...

In one of the 737 tech videos above, I think they were shown as having a castellated nut with cotter pin.

RE: Alaska Airlines flight forced to make an emergency landing...

Seems to be a culture difference be it lock wire or cotter pin to do the same job.

BAe aircraft have miles of lockwire on nuts and the technicians perform art work with it.

Bit like the Rudder nuts that have been coming off they are meant to follow a duplicate inspection and sign off process. Be it cotter pin or wirelock.

Quite what the pro's and cons are between the two methods I really don't know. Although personal experience with lockwire involved a hellish amount of blood leakage getting up the experience curve on the very basic stuff never mind the "art work" they do on fuel injectors and the like.

RE: Alaska Airlines flight forced to make an emergency landing...

a precursor... and a known potential problem.

"Alaska Airlines placed restrictions on the Boeing plane involved in a dramatic mid-air blowout after pressurisation warnings in the days before Friday's incident, investigators say.

The jet had been prevented from making long-haul flights over water, said Jennifer Homendy of the US National Transportation Safety Board (NTSB).

The NTSB also says the missing section of plane has now been found - in the back garden of a Portland teacher."

https://www.bbc.com/news/world-us-canada-67909417

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Its seems like most of the plug doors are fitted on N reg aircraft. Either Alaska or United.

Was surprised how few Max 9 there are outside the USA N reg.

RE: Alaska Airlines flight forced to make an emergency landing...

I wonder if the FAA directive is too narrow?
Apparently only planes with that configuration are being checked.
Being as there have been issues with missing bolts or nuts on the rudder assemblies of some planes and the strong suggestions that this is a missing bolt issue;
There may be strong suggestion that this is a bolt issue rather than a door plug issue.
That coupled with Boing's culture of profit over safety;
Maybe it's time to check every bolt on every plane.
It looks as if Boing never did.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Taken as snap shot form the excellent second video listed by 3D Dave. This is the top set of guides and pins. Lower ones go through the vertical spring guide and sleeve. Door is on the left so this is the upper right fixing.

Door very clearly goes up initially to move the main pins away and then looks to have a hinge assembly which allows the door to hinge down.

A number of comments on the video say that the door is commonly removed during interior fit out to allow for access for tools and equipment.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

So, no latch on the plug? (Too heavy?)
Just the interference bolts?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

I guess it was never intended to be removed. I note that Boeing cautioned their customers about the excessive cost in 'returning' the plug to a normal doorway.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

The emergency exit door would fit fine, a drop in replacement. Boeing may not have installed the required wiring that includes a solenoid to prevent the door from being opened in flight like was done on an Airbus by a passenger not too long ago and putting in that wiring would be a considerable expense.

I still believe it requires the FAA to approve the conversion to allow the airline to make use of the additional emergency exit to increase the number of seats.

RE: Alaska Airlines flight forced to make an emergency landing...

Well it must odds on that there simply no bolts installed on that particular air plane.

Even one bolt there would stop the door movement but seems inconceivable that a 3 month old plane could fail in another way.

Only way I can see is if the top bolts were there but the bottom ones not. Then there is a force trying to lift the door up, but hitting the top bolts which finally gave way?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

I doubt that the springs are strong enough to shear the top bolts if the bottom bolts are missing. They should only be strong enough to counter the weight of the plug (or possibly the heavier door), otherwise it would make closing the plug much more difficult than it needs to be.

RE: Alaska Airlines flight forced to make an emergency landing...

Don't they ever look in the box after they're finished, just to see if they forgot something.
I always check my Ikea fitting baggies. You know. Like just to make sure I didn't miss something..


--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Seems United has started finding multiple plug doors which are not as they should be.

RE: Alaska Airlines flight forced to make an emergency landing...

Yup

https://edition.cnn.com/2024/01/08/us/alaska-airli...

And ... get this!

Quote:

The (Alaska) airline had restricted the aircraft in Friday’s incident from flying from over the ocean to Hawaii to ensure the plane could “return very quickly to an airport” in case any warning lights in the aircraft went off, according to Homendy. That decision came after the plane’s auto pressurization fail light came on three times in the past month, Homendy said. It’s not clear whether there is a connection between the warning lights and Friday’s incident, she noted.

So, how is Alaska Air OK with continuing to fly with 3 warnings. I call the repair guy when I get 2 on my dishwasher! OK, how much you want to bet that there IS A FREEKING CONNECTION? This is starting to sound a lot like the Titanic Tour operator. Seems that they should have restricted ALTITUDE TO < 12,500 ft (No supplemental O2 needed for < 30min)

OMG. Voice recorder overwritten (when the 2h loop reinitialized ???).
How's that? What was it recording. Should have been shut down on landing, no?
Did it take more than 2 hours to get to the airport?


--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Murphy, what I meant was that the spring allows for some movement up and down as the plane pressurised, or not as the case seems to have been, but still enough to put a lot of force on the bolts.

But the main thing seems to be no bolts as far as an obvious error seems to be.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

What seems to be the rather undamaged looking door.


Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Good to know the door survived.

I have a hard time putting that in the plus column.

Quote:

The fail light came on December 7 and on January 3 and 4 –- the days leading up to the blowout, she said. Each time, the flight crew flipped a switch to the system’s backup, Homendy said, describing the move as “very normal.”

“They flipped it, they reported it, it was tested by maintenance and then reset.”

What is the "backup" for that? Could be pretty useful for pipelines and pressure vessels. Our operators currently have to hit the "Acknowledge" Button.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Sounds like the loose panel finally popped out. They should interview passengers who sat beside that panel on previous flights to see if anyone noticed whistling or hissing sounds.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (United officials)

bolts that needed additional tightening

RE: Alaska Airlines flight forced to make an emergency landing...

They probably changed seats. Wouldn't you?

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

After 3 alarms, this "accident" was a sure thing.
Pressure Indicator should normally have a probability of working correctly of around 0.975
1 alarm = 2.5 % chance of the PI being error. (1-0.025) = 0.975 chance of AC malfunction.
2 alarms = 99.93% chance of AC malfunction
3 alarms = 99.998% chance of AC malfunction.
Thems bet the ranch odds.
1 alarm is pretty damn critical from my perspective.
I was on a flight that turned back to the Dominican Republic because the cargo door opened.
Even that wasn't a really great feeling.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

I suggest cause was missing bolts or missing/wrong threadlock.

RE: Alaska Airlines flight forced to make an emergency landing...

From the looks of the above diagram plus the picture of the location of the loose bolts found on the United jet, if the bolts fell out of the bottom hinges, that would effectively detach the springs from pushing the plug down into the upper guide fitting.

Without that spring tension, a jolt (like turbulence?) could cause the plug to pop up, clear the upper guide fittings, and open, perhaps?

Here's a picture of one being inspected (posted on Facebook by Uretsky Aviation):

RE: Alaska Airlines flight forced to make an emergency landing...

There is supposed to be 2 bolts in the upper roller guides to also prevent upward movement. They appear to be installed in the photo above.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Roga50)

From the looks of the above diagram plus the picture of the location of the loose bolts found on the United jet, if the bolts fell out of the bottom hinges, that would effectively detach the springs from pushing the plug down into the upper guide fitting.

Without that spring tension, a jolt (like turbulence?) could cause the plug to pop up, clear the upper guide fittings, and open, perhaps?

The springs have the opposite function. They push the plug upwards and out of the upper guide fittings; i.e. they assist in opening the plug, by countering its weight and preventing it falling back down into the closed/locked position. The bolts prevent the door from moving upwards, by blocking the movement of the pins in the upper guide fittings and preventing it from sliding upwards on the tubular section of the hinge.

RE: Alaska Airlines flight forced to make an emergency landing...


From the photo of the failed opening. It appears the failure occurred at the upper guide roller. The picture is poor, but it appears the castellated nut and the upper guide track fitting as well as the roller are intact.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

The guide fitting and nut are not present in that photo, as far as I can see. It appears to be a photo of the open frame, showing only the guide pin. The guide fitting, bolt, and nut are all attached to the plug.

RE: Alaska Airlines flight forced to make an emergency landing...

I assume the guide rollers are primarily to facilitate alignment of the door until the other 12 fasteners can be installed. If the 12 bolts are missing the stresses may cause the guide rollers to fatigue and fail. This case makes the most sense to me as once the door is in the guides it will appear to be closed so any subsequent steps may be forgotten.

We don't have stringent procedures in maritime but I always tell people to never finger tighten a bolt as it has the appearance of being tightened. If you need to install the bolt and intend to tighten it later always back it off so that it's visibly loose.

RE: Alaska Airlines flight forced to make an emergency landing...

Your forgetting that the MAX is a 1960's franken creation with no health monitoring capability.

These systems lights come on and the pilots put them in the tech log and the only information the technicians have is what the pilots verbally or written tell them. The 1980's onwards ECAM systems record all system parameters and its relatively easy for them to down load and run through data processors to nail the reason for the light coming on and also a ruff location for the problem. So they know if its a capacity issue or a outflow valve, sensor etc etc. 737 you have a light go hunt the problem down.

We don't get an indication in the cockpit for all of them but basically every single opening in the hull which has a door / valve on it has a status recorded in the HMU (heath management unit) They even record the length of time for the status to change after being triggered.

With these older machines it was a hunt the fault game with certain issues. They were in and out the hanger, fault tested nothing concrete found tested satis on ground sent out again nothing happens for 10 flights closed.. week later same thing again. Until an experience base is built up this sort of thing is hunting a needle in a hay stack.

As for the Cockpit voice recorder, the older machines started recording when the power went on. These days there is some logic of when it records and stops. I think ours is when we turn the beacon on or it senses weight off wheels. Ours are 25 hour units.

But there is shall we say cultural issues. There is an ability to delete it. Some pilots in some cultures delete it after every flight as is their right under national law. They believe that the airline downloads it and uses it. I am not saying that it will have happened this time. More likely after landing because its a 1960's setup it will just keep on running with any power on the aircraft. On the Jetstream we were meant to remember to hunt the circuit breaker down and pull it after an incident. In the USA there very strong opinion on the CVR and what can and can't be done with it.

This situation after the excitement of the incident its understandable why the pilots forgot. The flight safety incident team should have immediately contacted the technicians and instructed them to secure the CVR. I know its on my works incident checklist. And there are technicians on that team that gets formed to coordinate. They have exercises every couple of months to keep current.

RE: Alaska Airlines flight forced to make an emergency landing...

I don't understand the "stop pad" and "stop fittings", but I haven't seen a clear picture of them with a plug installed and closed.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (TugboatEng)

I assume the guide rollers are primarily to facilitate alignment of the door until the other 12 fasteners can be installed. If the 12 bolts are missing the stresses may cause the guide rollers to fatigue and fail. This case makes the most sense to me as once the door is in the guides it will appear to be closed so any subsequent steps may be forgotten.

Yes, the guide pins/rollers and corresponding fittings on the plug are primarily to align the plug, not to retain it under pressure. The 12 stop fittings on the plug and stop pads on the frame are permanent structural components. There are no fasteners for them (for opening/closing the plug; obviously there is permanent hardware attaching them to the plug and frame). The plug simply slides downwards to engage them; with the plug in the fully closed position, the stop fittings on the plug transmit the pressure force onto the stop pads on the frame.

Only 4 bolts are involved in normal opening and closing of the plug, two on the guide fittings at the top, and two through the collars which slide over the tubular section extending out of the hinge at the bottom. The bolts are intended to keep the stop fittings and pads aligned.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (MintJulep)

I don't understand the "stop pad" and "stop fittings", but I haven't seen a clear picture of them with a plug installed and closed.

The "stop pads" are the 12 tabs sticking out from the frame. The "stop fittings" are the corresponding 12 tabs sticking out from the plug. It's essentially the same attachment method as a DSLR camera lens, if that helps, just with sliding rather than rotation.

RE: Alaska Airlines flight forced to make an emergency landing...

Yeah OK. Anyway I solved my problem in 2018.
My ticket purchase app will not proced to checkout when
If InStr(AC_TYPE, "max") = True
Print "WARNING Unapproved AC Type"
Exit Sub

Think I must change "max" to "boeing"

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Seems like wishful hoping for all 12 stop pad/fittings to share the load anywhere near equally.

What actually holds the pressure in?

RE: Alaska Airlines flight forced to make an emergency landing...

If you look at the construction of the door the horizontal stiffeners are quite robust while the vertical stiffeners are slender. This means the door will be somewhat flexible about a horizontal axis which will help it share the load amongst the stop fittings vs a more rigid door.

RE: Alaska Airlines flight forced to make an emergency landing...

The structure has to take negative pressure 0.5 PSI I think it is before the safety valve triggers to prevent implosion.

I presume the stop pads are to distribute the load to the rest of the hull structure. Any less and you would have to beef up the ribs and stringers. And have cylindrical buckling issues.

The pressurisation system is meant to control things so you don't blow the ears out of everyone onboard. So you really want 500ft/min or less. The aircraft can descend and we do at over 3000 ft/min, above 10k, most company's have limits to reduce that to some max value below that. But 1500/2000ft/min is normal. Cabin at 41k will be at 8000ft. Which gives 14 mins to get it down to sea level (it actually lands with -500ft) . The aircraft can do it in less than 13 mins. So you "catch the cabin" so things have to be protected against implosion.

Again its a 1960's system... Modern aircraft have a schedule which is linked to density and perceived pressure change on the ears so work on a rate of pressure change. So may start off at 800-1000 ft/min high up then reduce to 350ft/min at lower altitudes. I have never managed to catch the cabin on the A220 and I have done some border line emergency descents rates due to Air traffic restrictions. Q400 it was almost daily.

RE: Alaska Airlines flight forced to make an emergency landing...

$ 13B (8%) loss in the market value yesterday. That will go lower still.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

There is some sort of fastener in the stop fittings.

Perhaps to hold on a wear pad and shims?



RE: Alaska Airlines flight forced to make an emergency landing...

I'm thankful the door missed the tail on the way out - I believe that's brought down aeroplanes in the past.

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

RE: Alaska Airlines flight forced to make an emergency landing...

An update brief

https://www.youtube.com/watch?v=kGWLBLb9Pm4&t=...

I must say I am well impressed with that lady. Excellent communicating technical content without dumbing down.

And she obviously "gets" the engineering and understands it.

RE: Alaska Airlines flight forced to make an emergency landing...

Seems on the door there is evidence of fractured guide fittings.

RE: Alaska Airlines flight forced to make an emergency landing...

Looking at the relative size of the guide fittings and stop fittings, I think the guide fittings will remain engaged after the plug has moved upwards off the stop fittings, transferring the full pressure load onto the guide fittings and hinges. That makes the fracture unsurprising to me, and a consequence rather than a cause of the problem.

RE: Alaska Airlines flight forced to make an emergency landing...

As an aside I had 3 pax out 280 moved yesterday ask me about if we had something similar.

One had asked the cabin crew who pointed them towards me.

The public are definitely getting more upfront asking about stuff in the media.

Explained what had happened to the CC during the cruise and the next two they dealt with themselves. Much too thier own amusement after they got a compliment by another pax listening in about thier technical correctness. Which they blamed on me...

RE: Alaska Airlines flight forced to make an emergency landing...

Those connections look pretty flimsy. Is that sort
of thing common in aerospace?

RE: Alaska Airlines flight forced to make an emergency landing...

Such connections are not uncommon in aircraft structures. The plug in question not an especially novel design. It utilises the same means of attachment as the functional emergency exit door it replaces. That exit door configuration existed on 737s prior to MAX.

RE: Alaska Airlines flight forced to make an emergency landing...



Humour that's doing the rounds

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

OMG. Voice recorder overwritten (when the 2h loop reinitialized ???).
Freaking incredible.
The micro chip in my dash cam records good quality video, speed, time and GPS coordinates.
It will run several days before over-writing.
Voice recording? The chip in my dash cam would probably record weeks of audio before over-writing.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Murph 9000)

Looking at the relative size of the guide fittings and stop fittings, I think the guide fittings will remain engaged after the plug has moved upwards off the stop fittings, transferring the full pressure load onto the guide fittings and hinges. That makes the fracture unsurprising to me, and a consequence rather than a cause of the problem.

Having just watched today's NTSB media brief, this was actually stated in it by one of the lead investigators, at 29:12 in the livestream.

NTSB Media Brief - Alaska Airlines Flight 1282 (Jan 8) livestream @ 29:12

RE: Alaska Airlines flight forced to make an emergency landing...

Why do you need a dash cam? So you can record other bad drivers? What are you going to do with it?
I have one, but only because it was on sale, at a good price.

RE: Alaska Airlines flight forced to make an emergency landing...

If it's Boing, I'm not Going.

Boing??
I've checked the spelling several times:

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

A couple of years ago, when Boeing was going through a rough patch due to the 737 (no, this wasn't after the MCAS thing, it was more recent than that), I picked up some shares at $121 per share...They're still ok now at what, $229, but I maybe should have cashed out at $250.

The question is, should I pick some up now?

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (waross)

Quote:
OMG. Voice recorder overwritten (when the 2h loop reinitialized ???).
Freaking incredible.
The micro chip in my dash cam records good quality video, speed, time and GPS coordinates.
It will run several days before over-writing.
Voice recording? The chip in my dash cam would probably record weeks of audio before over-writing.

A few years ago, at SFO airport, an Air Canada flight lined up with a an occupied taxiway for landing. There would likely have been well over 1000 casualties if the plane impacted the other loaded planes on the ground. They came within 15 feet of crashing. The flight data recorder was not preserved. No disciplinary action was taken. Good news, they stopped using that flight number.

https://en.m.wikipedia.org/wiki/Air_Canada_Flight_...

RE: Alaska Airlines flight forced to make an emergency landing...

RE: Alaska Airlines flight forced to make an emergency landing...

That's not one of the bolts that holds the plug in place when it's closed. That's the top of the tubular section that extends out from the hinge, with the green collar around it that should be attached to the plug (and was presumably torn off by the forces presented by the airflow when the plug popped open in flight). The bolt which prevents the plug opening would have gone through a radial hole in that collar and the tubular section of the hinge. The visible nut and washer there, as far as I can tell, is just to retain the plug on the tubular hinge section when it's fully open (otherwise it would just slide off).

There's a bit of a mystery around the "loose bolts" that keep being mentioned. Just being loose would not have allowed this incident to occur, they have to be completely missing/removed to allow the plug to move upwards and disengage the stop fittings/pads. If they are loose, but still in their correct bolt holes and have the cotter pin correctly in place, they should still function adequately to prevent the plug from opening. It's not clear exactly what is being communicated by the mention of loose bolts being found on other MAX 9s. It's probably not desirable to have them too loose, but shouldn't be imminently catastrophic; the plug does not depend on them being tight to keep it in place.

Edit: That's for the 4 bolts involved in opening and closing the plug, and the nut on the end of the tubular hinge extension. Obviously there are other bolts around, possibly related to the plug and frame, which could be critical if insufficiently torqued.

RE: Alaska Airlines flight forced to make an emergency landing...

Thanks murph...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Murph 9000)

Loose bolt talk

You are mostly correct Murph. No bolts keep the plug closed. The pads do not keep the plug closed, they act in the other direction and absorb negative pressure and minor distortion. The plug is held in place by the interference with the frame when in the lower position or perhaps by the roller pin and lower hinges. Two bolts in the pin/catch keep the plug on the track. The mystery is if those bolts went missing and how did the door move up against the force of air pressure? The roller pin and hinges are intact. The bolt in the photo seems completely backed-out, but perhaps the NTSB removed a dangling part and did this.

RE: Alaska Airlines flight forced to make an emergency landing...

There seems to be a circulation of loose and missing hardware in the news.

1) In the rudder control system, which disables pilot inputs, but not the automation input to control yaw stability.
2) Highly suspected in the departure of the door
3) In checking to see that all door hardware is in place, fasteners intended to hold portions of the door brackets to the door have been found unsecured.

The main communication seems to be that there are gaps in the Boeing final assembly area when it comes to ensuring that hardware is where it is supposed to be.

For all I know this is common at all aircraft makers, but the door departure with instant coverage and plenty of people to interview has drawn more attention to it than any of the other 10,000 other manufacturing problems that have made their way into products with some having fatal results.

If I were CEO of Boeing I would be on the factory floor yesterday asking a lot of questions. Were it just one door, sure, bad day. But finding other fasteners loose while inspecting the doors? That's at least a chain 3 deep of QA and QC and manufacturing engineering likely to get fired unless they can demonstrate sabotage has taken place.

RE: Alaska Airlines flight forced to make an emergency landing...

And now I am reading that both Alaska and United have found loose retention bolts as they have started inspections.
These bolts are installed at Spirit.
It will be interesting to see what they find in unbuilt and unshipped hulls.

The only flight that I ever skipped because of the plane was a flight in China on a Russian plane.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (jrs87)

The pads do not keep the plug closed, they act in the other direction and absorb negative pressure and minor distortion.

No, the stop pads very much do absorb positive cabin pressure (i.e. the normal case in flight). The "stop pads" on the frame are outboard, and the "stop fittings" on the plug are inboard when the plug is in the fully closed position, transmitting positive cabin pressure into the frame via the pads. The 4 bolts (2 through the guide fittings, blocking the pin; and 2 through the collar and tubular hinge extension) prevent the door sliding up vertically and disengaging the stop pads and fittings. The plug has to take a positive pressure delta of around 8 psi, and only around negative 0.5 psi (I'm not sure if those are the exact numbers for the MAX, but they should be a rough approximation).

The guide/roller pins and hinges are not really part of handling the positive pressure, although they might be what handles negative pressure.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Murph 9000)

Stop pads

Thank you for the clarification. Very much appreciated. It seems the inflight pressure on the pads would keep the door plug in place unless the plug was partly open before pressurization.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

These bolts are installed at Spirit.
There have been strong suggestions that the bolts may have been removed and the plugs opened at the Boing plant.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

It's certainly been suggested that these doors may have been used for getting things in and out of the cabin during fit out, which could even include the airlines, if they made any changes after delivery.

RE: Alaska Airlines flight forced to make an emergency landing...

I'm guessing that the loose bolts that were found by United are the bolts holding the door/plug lower hinge piece onto the door/plug frame. The part that slides up and down on the hinge tube. The upper bolts retaining the plug in position should still hold the plug in place if this was that case. That might be why the upper pin was found damaged.

RE: Alaska Airlines flight forced to make an emergency landing...

The door must move upwards so that the side pins may clear the stop pads.
There is over-travel on the top guide to allow clearance tolerance so that the stop pins may safely clear the stop pads before dropping in behind the stop pads.
As the door crept upwards, as soon as the stop pins were clear of the stop pads, the door departed.
Th door had not yet lifted far enough for the guide pins to clear the guides so that the guides were damaged.
Four bolts is nice symmetry, but even one bolt should have prevented the door from moving upwards.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
While this has nothing to do with the door itself, other than it ending-up where it did because of the failure, an Apple iPhone was found which appears to have fallen from the plane and not only did it appear to be undamaged, is was still fully functional (this would be a great opportunity for an Apple advert).

Passenger phone found on ground after Alaska Airlines emergency

https://abcnews.go.com/US/passenger-phone-found-gr...

And yes, the phone was in 'Airplane Mode' when it was found winky smile

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

What sort of bolts are they? How do they work? What does “loose” mean?

RE: Alaska Airlines flight forced to make an emergency landing...

There is a bracket that goes between hinge and the frame of the door that has what appears to be 4 fasteners. It slides on the hinge guide. At least 3 visible bolts were clearly loose in that joint.

RE: Alaska Airlines flight forced to make an emergency landing...

“Loose” means not torqued to spec.
Std aerospace bolts, probably Titanium, possibly CRES.
The loose bolts seem to be on the door structure, not 4 used to prevent the door from moving upwards, which must happen to allow the stop pads to clear and allow outward movement.
Loose bolts still not good, as could lead to fatigue failure.
The stop pads are not “flimsy”. We don’t put extra weight into the structure beyond what is required.

RE: Alaska Airlines flight forced to make an emergency landing...

And fuselages, with the doors installed, are statically tested to 2X max design pressure.

RE: Alaska Airlines flight forced to make an emergency landing...

Search Blancolirio on youtube, he is an airline pilot and is the best for explaining anything aircraft accident related.

In one of the photos in this thread, there is one bolt at the bottom of the fitting that does not look tight.

It was the lack of cabin pressure that allowed the door to become disengaged with the lugs, and not being secured would have moved out of position and off it goes.
Be happy there was not a child seated next to it. There should be no seats next to a plug door, and that weight savings can be put into some stronger materials where needed.

No matter what I would still question material choices for what all those poorly attached fittings are attached to, just looks like a problem waiting to happen.

RE: Alaska Airlines flight forced to make an emergency landing...

engines - once again you demonstrate your ignorance. There is nothing to indicate a material problem. Nothing. As far as materials these doors are essentially the same as 10’s of thousands successfully flying every day.

RE: Alaska Airlines flight forced to make an emergency landing...

Those springs on the hinges are to hold the door up when it is open or about to be opened.
If the door slid downwards when it was open, then it wouldn't close.
The stop pins would impact in front of the stop pads instead of behind them.
That said, the springs must be strong enough to support the weight of the plug, and probably strong enough to support the weight of a functional door.
Ther must have been some friction holding the door down in the closed position.
Absence friction the springs would have lifted and disengaged the door.
I surmise that vibration on the ground when the internal and external pressures were equal may have allowed the springs to slowly work the door upwards until the stop pins were just clear of the stop pads but the top guide was still engaged.
The differential pressure at 16,000 ft alt then fractured the still partially engaged upper guides.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

, an Apple iPhone was found which appears to have fallen from the plane and not only did it appear to be undamaged, is was still fully functional

I imagine the terminal velocity of a modern cell phone is quite low. A brush with a tree leafy branch (this was Oregon) on the way down can only help.

RE: Alaska Airlines flight forced to make an emergency landing...

the hull is pressurised to -500ft as soon as the doors are shut and the engines are started.

RE: Alaska Airlines flight forced to make an emergency landing...

Quoting waross

waross, how do you feel about these comments?

Those springs on the hinges are to hold the door up when it is open or about to be opened.
If the door slid downwards when it was open, then it wouldn't close.
The stop pins would impact in front of the stop pads instead of behind them.
That said, the springs must be strong enough to support the weight of the plug, and probably strong enough to support the weight of a functional door. Perhaps counterbalance like garage door or double hung window, spring holds it were other force puts it.
There must have been some friction holding the door down in the closed position.
The spring is basically neutral when the door is closed
Absence friction the springs would have lifted and disengaged the door.
I surmise that vibration on the ground when the internal and external pressures were equal may have allowed the springs to slowly work the door upwards until the stop pins were just clear of the stop pads, but the top guide was still engaged. The aircraft left the factory with the track lock bolts not installed but with the plug set but not fixed in the down position.
The differential pressure at 16,000 ft alt then fractured the still partially engaged upper guides. 14,000 feet, climbed after rapid decompression another 2,000 feet before diving. Fractured guide as last failure point is plausible.

RE: Alaska Airlines flight forced to make an emergency landing...

The root cause is the restraint bolts were not fitted to stop movement.

The failure mode after that is interesting but not really relevant.

There should be a paper work trail with duplicate signatures whenever the doors are closed. If that paper work doesn't exist then a cert of Airworthiness shouldn't have been issued.

We see it in the techlog when the technicians open the normal emergency exits. One stating they were open and another entry saying they were closed. Which I might add we have sensors on and will trigger a caution in the front if they are not "green" we don't see them on the door synoptic page normally unless they are open.

I believe during a C check the job cards have all these signatures and listings. And the CAMO ensures that its all done and signed off before issuing the certificate of Airworthiness.

RE: Alaska Airlines flight forced to make an emergency landing...

I was thinking when they released the original pilot transcript that it was soumding rather "informal".

Did no one ask or state they were squawking 7700?

Or use the words mayday? Or even panpan?

I though everyone used FL 100, not ten thousand feet??

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Transition altitude in the USA is 18000ft before you set 1013 so its normal for them.

By the sounds of it they were struggling with the stabilisation to get it in.

Personally a big bang like that rapid depressurisation I would be doing a compromised airframe decent and approach so the speed would be back at 210knts. Early gear down in case there is issues with that. They were loaded with fuel so its not as if that was an issue taking drag hit and fuel burn. In fact getting rid of it is a bonus.

On a mayday the pilot dictates the requirements so you just tell them your required track miles and they will give it. To be fair the controller was giving hints that it was available and maybe they should.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

The aircraft left the factory with the track lock bolts not installed but with the plug set but not fixed in the down position.

That's been determined and reported already? I've only heard that they have yet to be recovered.

RE: Alaska Airlines flight forced to make an emergency landing...

It remains to be 100% confirmed, but NTSB have already said that they believe the incident was caused by the plug moving vertically up off the stop pads, allowing it to open as designed. The fractured guide fittings are an obvious consequence of it opening while under pressure. The only way that should be possible is with all 4 locking/retaining bolts missing. There shouldn't be enough force available to shear those bolts, even if there was just one present, and it seems unlikely that fatigue would be an issue due to the age of the aircraft. They have the plug, so they can say with a high degree of confidence that the stop pads (on the frame attached to the hull) and stop fittings (on the plug) didn't fail.

It's now more a case of trying to figure out if the bolts were ever fitted, who failed to fit them the last time the plug was closed, and why they failed to fit them. There's a small chance they might have been improperly fitted, but just missing seems quite likely. There's a secondary question about why different bolts that hold some of the fittings to the plug have been found loose on other MAX 9s, but it doesn't look like those other bolts being loose would cause the plug to exit stage left; that's just some other shoddy workmanship that has been discovered in the same area.

RE: Alaska Airlines flight forced to make an emergency landing...

You wonder then if the door had moved a little bit, enough to cause a small leak at the base or top of the door, but not enough to detach itself from the stop pins.

I'm not surprised they've come to that conclusion as it looks like an almost perfect door opening operation, just when it wasn't supposed to.

Those locking/retaining bolts though are pretty small, easily misplaced and not exactly super obvious. No Red paint or warning notice e.g. "BOLT HERE when closed". Will be interesting to see if its even on the checklist.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...



Just a pic how the Canadians do it

RE: Alaska Airlines flight forced to make an emergency landing...

It certainly does appear that at least some of the bolts were missing. However, they're still looking for one of the lower hinge pieces that is bolted to the plug and the spring that pushes it up. In the pictures posted above, the other one is visible still on the airframe and not attached to the plug. So, the failure likely is not as simple as the bolts being missing and the plug popping out of the airframe. The fix won't be as simple as checking that the 4 bolts are installed either.

In the end though, it squarely points to Boeing having serious QC problems.

RE: Alaska Airlines flight forced to make an emergency landing...

2
No, it appears quite simple that the 4 restraining bolts were missing and this allowed the door to open. There is no other plausible cause at this time (though we might yet be surprised). Once the door opened, it swung down on the hinges, as it is designed to do. But it is now in the airstream, so it likely tore off part of one or both hinges as it departed the aircraft.

Yes, a significant quality escape somewhere. As is the number of other loose bolts found in the door structure. See:
https://www.democracynow.org/2024/1/9/boeing_warni...
https://www.msn.com/en-us/money/companies/boeing-s...

RE: Alaska Airlines flight forced to make an emergency landing...

It's already been PROVEN by inspection that OTHER bolts in the door assemblies have been found loose...

RE: Alaska Airlines flight forced to make an emergency landing...

yes, but those loose bolts do not appear to have anything to do with the plug door opening.

RE: Alaska Airlines flight forced to make an emergency landing...

None of the other loose bolts could in any way allow the door to leave. If the bracket retaining bolts had been removed the spring that is to push the door out of position could no longer to that; it would eliminate a way to get the door to leave. Sort of an anti-defect for this accident. As long as the upper keeper bolts were in place the door could not move off the stops.

RE: Alaska Airlines flight forced to make an emergency landing...

Our friend Juan has a good series of videos on this

https://www.youtube.com/watch?v=ubCQZtLTAug&t=...

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

The spring is basically neutral when the door is closed
No, The springs are compressed when the door is closed.
In normal closed position the springs are compressed and pushing upwards.
This is normally restrained by the four bolts on the factory floor.

Quote:

It's already been PROVEN by inspection that OTHER bolts in the door assemblies have been found loose...
.........
yes, but those loose bolts do not appear to have anything to do with the plug door opening.
All points to Boing's deteriorating standards and procedures.
If this is the best that they can do after the original crashes, maybe Boing should not be building civilian planes anymore.
Let's see what the market decides over the next couple of years.
It is certainly a strong disincentive to not buy Boing.
MBAs in purchasing may start to look past the pennies and start asking;
"What will happen next to ground our planes."
Sorry about you pension John.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (All points to Boing's deteriorating standards and procedures.
If this is the best that they can do after the original crashes, maybe Boing should not be building civilian planes anymore.)


One of these times, something serious could happen. bomb

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

...cockpit voice recorders. There should be the requirement that they cannot be 'turned off'.

"It is an anomaly in the era of inexpensive and expansive digital storage, when the phone of each passenger onboard a flight could easily have more capacity than the plane’s voice recorder.

Now, Homendy wants the recording standard to change.

She is calling on the Federal Aviation Administration to require a 25-hour recording window for the cockpit voice recorder in all aircraft – a duration that is already a standard requirement under European airline regulations."


https://www.cnn.com/2024/01/08/us/ntsb-chair-calls...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Dik)

One of these times, something serious could happen.
I love your understated sarcasm, dik.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...



Daily Mail.

It is plausible that the locking bolts were over-tightened and fractured the retaining track?

RE: Alaska Airlines flight forced to make an emergency landing...

If that happened as long as the "vertical movement arrestor bolt(s)" would prevent the door from moving off the stops.

It would tend to bend the guide wall to decrease the width of the groove, rather noticeable, and the NTSB would have mentioned it. I expect the portion that was damaged bent the guide to increase the width of the groove.

RE: Alaska Airlines flight forced to make an emergency landing...

The thing that gets me is that whilst weight is very important, for a door plug which is not used, why they don't have secondary or better locks between the two parts, plane and door.

So e.g a set of C shaped clips to go over say 4 of the stop pads which could then be fixed to the door using cables so they don't get lost if the door is removed at any point.

Those bolts look quite small and difficult to fit.

It's rare for me to praise the Dailly Mail, but that is a very good illustration and explanation of the issue

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (LittleInch )

a set of C shaped clips to go over say 4 of the stop pads which could then be fixed to the door using cables so they don't get lost if the door is removed at any point.

The failure happened because the parts that are already defined as necessary didn't get installed correctly.

Adding more parts to install is not how to solve such failures.

RE: Alaska Airlines flight forced to make an emergency landing...

If everyone does their job correctly when fitting and maintaining the plug, it has double or quadruple redundancy in the locking. I suspect that just a single bolt in any of the 4 holes would be sufficient to prevent opening in all but the most extreme circumstances, and two or more should make it impossible without hull damage to distort the frame. There shouldn't be that much force on the bolts in normal service.

I agree that it looks like it's difficult to fit the bolts. Every picture I have seen of them fitted has the nut and cotter pin on the cabin side, so the bolt has to be inserted by reaching around behind the fittings into the narrow gap between fitting and skin. It makes sense to have the nuts on the cabin side, as it would be an even bigger problem to insert and secure the cotter pin on the skin side, but the overall procedure looks a little difficult.

RE: Alaska Airlines flight forced to make an emergency landing...

It's about making it much easier to see that they are not fixed in place or get lost. Plus those bolts seem rather small.

This door is not removed other than a major strip down so should be positively held jn place IMHO.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

I'm of the understanding that other models use the same door plug. If so, then failure to fit the bolts must be related to the work instructions related to the MAX 9.
Also, the way the bolts are fitted, it seems that neither the top nor the lower bolts can require to be torqued, as this would damage the fitting it passes through. The bolt is really just a pin, with castellated nut and cotter pin to keep it in place. Media reports of 'loose' bolts don't seem relevant.

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

The loose bolts are on neighboring fittings and were discovered during the inspection of these doors on other aircraft. Loose bolts have previously been reported in the rudder control system. Loose fasteners are very much a concern, though not directly related to the departure of the door. None of the bolts found loose or missing should ever be loose or missing.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (waross)

No, The springs are compressed when the door is closed.
In normal closed position the springs are compressed and pushing upwards.

That's my take too, the plug door is being pushed upwards so it can be easily lifted by the operating staff. It makes me think that the plug door without and bolts could move upwards easily when the aircraft hits any bumps while on the ground and not pressurized but would it not easily move back down without being pushed.

RE: Alaska Airlines flight forced to make an emergency landing...

The larger magnitude bumps are in the upward direction, tending to seat the door. In the downward direction is mainly free-fall which exerts no force. Vibration and elasticity of the airframe can allow shaking but there isn't much deflection in a typical fuselage, but that will be symmetric.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (3DDave)

The loose bolts are on neighboring fittings...
Thanks. That's a whole 'nother story. I thought it was in reference to the stop bolts that held the door in position to keep it from moving up. Now I've seen pictures of the closure hardware bolts hanging out. A much bigger issue, to be sure. Now I see why the FAA has kept the planes on the ground. Nobody is even sure what to check for yet.

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

10000 loose bolts flying in close formation ;)

RE: Alaska Airlines flight forced to make an emergency landing...

Weird, my post with a link to Boeing's job application page got removed.

RE: Alaska Airlines flight forced to make an emergency landing...

On alot of commercial BB's links to jobs are removed due to free advertising which is worth quite a bit to the recruiting pimps.

RE: Alaska Airlines flight forced to make an emergency landing...

Murph the A220 is 272 486 computers flying in formation apparently.

Even the toilet has one.

RE: Alaska Airlines flight forced to make an emergency landing...

I can just see... cruising along at 37,000 and hit a slight 'bump'... that dislodges a door that is not properly secured... Why would terrorists strike an Alaskan airline?

It begs the bigger question... how much other stuff has Boeing put out that has been improperly assembled.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Weird, my post with a link to Boeing's job application page got removed.)


Maybe Boeing is looking for new employees... and management thought it was a posting by them?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

It's more likely it's taxing and takeoff runway lights it gives the high g bumps

RE: Alaska Airlines flight forced to make an emergency landing...

https://leehamnews.com/2024/01/11/alaska-1282-isnt...

This is a good discussion of the situation. My guess is that every Boeing plane (of any model) with a plug in place of a door will be subject to added inspections.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Alaska Airlines flight forced to make an emergency landing...

I think all makes will be checking the pins required or not...

Although I can't think of others with plug doors. But I am particularly talent limited on spotting and aircraft specs unless I have to waggle a stick of one

RE: Alaska Airlines flight forced to make an emergency landing...

"Some Boeing critics and the uninformed suggest that the door plug is a remnant of the 1997 merger with McDonnell Douglas Corp. and that MDC-inspired cost-cutting led to the door plug design. Some others suggest the same cost-cutting culture is responsible for launching the MAX.

Both of these theses are wrong, fundamentally because this is a quality control issue and not an airplane issue like the MCAS design. But on the facts, the origination of the MAX was a parallel design study against a new airplane design during the years leading up to the July 2011 launch of the MAX."

That doesn't make me feel any more comfortable... and I'm not sure it is true.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Nah it dates back to the 1960's and prior approval.

It was legal on the NG so don't change anything even if it's safer

Although to be honest in this case I really thing it's a quality issue not design

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
It's been reported that a second Apple iPhone has been found that had fallen from the Alaska Airlines flight which lost the door over Portland. And yes, it was still functional with little or no apparent damage.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

Is this senior plausible? *

1. Exit is open and ready to be closed.
2. Plug was pushed down against the springs and the top tracks and roller pins seated.
3. Two upper cross locking bolts are forgotten but the spring does not push the plug upward and out of the tracks because the stop pads are conical in the fit functions as a strong enough detent.
4. Over time the springs work the plug up leading to leaks detected 3 times.
5. Under flight pressure the stop pads instead of mating, pop past each other and the door blows out.

*Are the stop pads indeed conical to any degree?
By the way, I know of the two upper lock bolts, I hear of two lower lock bolts but have not seen them. The hinge spring over-travel arrester bolts do not lock the plug or do they? As a whole, this method of plugging the exit seems sketchy.
p.s. I like the term anti-defect used by 3DDave.

RE: Alaska Airlines flight forced to make an emergency landing...

I'm pretty certain the bolts which pass radially through the green collar and hinge extension tube are the lower locking bolts, not over-travel bolts. There's a nut and washer on the end (top when closed) of the hinge extension tube, which I believe is to prevent the plug coming off the hinges when open.

RE: Alaska Airlines flight forced to make an emergency landing...

what's the deal with locking wire?

RE: Alaska Airlines flight forced to make an emergency landing...

New from the 737 tech YouTube channel, clarifying the design and function of the plug, and a few new details (e.g. the stop fittings on the plug have adjustable stop pins secured with lock wire):

737 Technical Aspects of AS1282 FAQs

RE: Alaska Airlines flight forced to make an emergency landing...

I don't see Alaska Air as entirely blameless. They had a high enough concern to severly restrict operations of the AC. That indicates it had some probability of failure, apparently from depressurization, yet they restricted the maximum distance from a runway. That makes no sense at all, if the worry is about decompression. If I'm worried about pipeline blowouts, I restrict the operating pressure, not how far I can pump product. The plane's maximum altitude should have been restricted. This makes the lack of a major disaster just freeking luck. That don't cut it for me. Yet Alaska Air isn't catching any sh!t at all.

Quote:

"And she said Alaska’s decision to restrict the jet from long-range routes over water was not required by regulations but was a precautionary measure the airline takes voluntarily to provide an additional safety margin when any important systems show any sign of a repetitive problem."

If that is true, what exactly was the reason for the restriction? Just "too many alarms"? Nobody looked at the alarm log and said, uh it's a pressure problem. Nobody looked to see what the hell it was and deduce the appropriate flight restriction. Really? Nobody?

Quote:

"Intermittent warning lights indicating a brief reduction in cabin pressurization had occurred on flights of this new MAX 9 on Dec. 7 and then again on Jan. 3 and 4, (2 in the previous) two days before the incident."

They had 3 warnings. Increasing in frequency. That is in itself a signal of increasing danger. Then they reach a daily basis. What the hell are they thinking. Keep the plane flying! Just when, or how many warnings does Alaska Air need to stop and figure out what's wrong? 2 per day? 3? 5? What's their limit? It's obviously much higher than mine. Do I have to ask "Hey, how many warning lights did you get lately" each time I board. It looks to me like they are not interested in passenger safety at all. Just giving lip service.

Quote:

Homendy said the policy to restrict it from doing so at any sign of a system issue is “an extra step that Alaska Airlines put in place.”

Guess what. That does no good, none at all, if you do not take the right precautions. FAA, time for a new regulation. PROMENATELY POST THE NUMBER OF WARNING LIGHTS RECEIVED IN THE LAST 30 DAYS and ANY CURRENT RESTRICTIONS ON OPERATIONS OF THE AC. POST IT ON THE PASSENGER ENTRANCE RAMP IN 8" TALL LETTERS. I'll make my own decisions, thank you. With immediate 4x ticket cost cash refunds for anyone deciding not to take their joy rides.

I want to know exactly when an airline can make you fly on whatever POS that they decide to field at the other end of the boarding ramp. What exactly classifies as "not flight worthy", besides the obvious. Are all warning lights 👍? Doesn't look like it.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Hi Murph9000,

Thanks, the video you linked to sends my entire contribution to rubbish bin. Good find.

https://youtu.be/kKSNdqtG3dY



RE: Alaska Airlines flight forced to make an emergency landing...

Referencing this video: 737 Technical Aspects of AS1282 FAQs

If the stop pins are not adjusted correctly then pressurization loads will be taken through the guide track and roller. Given that there are stop pins and stop pads that are intended to transmit the pressurization loads, we could speculate that the guide track and roller are not designed for pressurization loads.

This might explain the reported fracture of the guide track.

Also, if the stop pins are not adjusted correctly, then pressurization will cause the plug to move outward more than intended. This would relax the gasket, possibly explaining the reported depressurization alarms in the days prior.

RE: Alaska Airlines flight forced to make an emergency landing...

But, but

Quote:

we have no indications whatsoever that this (decompression warning lights) correlated in any way to the expulsion of the door plug and the rapid decompression.”

Shush. Nobody even suspects. The probability is only 99.9999

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

New speculation, Boeing accidentally switched the door with another Spirit fuselage's door. The mismatched micro adjustments went unnoticed. This presumes Spirit was responsible for the adjustments.

RE: Alaska Airlines flight forced to make an emergency landing...

"But Homendy said she believes these three incidents are likely unrelated to the door plug blowout and that Alaska’s decision makes sense."
Three pressurization alarms followed by a plug blowout, "likely unrelated"
There goes my respect for Homendy.
Note to Alaskan; The next time that you get a pressurization alarm it may be prudent to check that all the doors and plugs are secure.

And this from Boing;

Quote (Seattle Times)


CEO Dave Calhoun, the new Chief Operating Officer Stephanie Pope, Chief Safety Officer Mike Delaney and Stan Deal, CEO of the Commercial Airplane division, all spoke at noon before about 500 employees in the factory where the MAX is assembled. The meeting was webcast to all Boeing employees.
He said Boeing will try to restore airline confidence by “our willingness to work directly and transparently with them, and to ensure they understand that every airplane that Boeing has its name on that’s in the sky is in fact safe.

The check's in the mail
and
I'm from the Government NTSB and I'm here to help you.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

The more I look at this the worse I think the design is.

Depending on many variations for component dimensions and assembly variation, as the plug is moved down the interaction between the Upper Guide Roller and the Upper Guide Track might pull the plug inwards, or it might push the plug outwards.




RE: Alaska Airlines flight forced to make an emergency landing...

I believe the pin bracket is adjustable, hence the use of bolts rather than rivets to fix it to the fuselage.

RE: Alaska Airlines flight forced to make an emergency landing...

Was there a huge change in Boeing quality after McDonnell Douglas took over? Douglas' manner of doing business?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (3DDave)

I believe the pin bracket is adjustable, hence the use of bolts rather than rivets to fix it to the fuselage.

So that's:
12 stop pins
2 guide brackets
Maybe 2 hinges

16 points of adjustment at assembly to get one plug to close and seal correctly.

RE: Alaska Airlines flight forced to make an emergency landing...

Does the roller guide system have some inherent rattle room?


RE: Alaska Airlines flight forced to make an emergency landing...

4
(OP)
Alaska Airlines is considering a new solution to their problem:

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

Was there a huge change in Boeing quality after McDonnell Douglas took over? well, there was a HUGE change in culture. I was there until 1999, two years after the “buyout” of Boeing. The St Louis mgmt “tong” basically took over and proceeded to destroy the engineering culture. The 787 program was a complete business fiasco, to the tune of $100B+ in losses, due to the “outsourcing” model and other shortcuts. The delays and cost overruns on that program meant there were no resources to develop a new single aisle aircraft. And the mgmt focus was on the stock price, which they have tried to prob up with 10’s of billions of stock buybacks. When AA was about to place a huge order for A320neos instead of 737NGs, Boeing mgmt paniced and launched the 737Max on a rush schedule with limited resources. Hence the string of bad design decisions. The Max grounding and then Covid had a huge aircraft production impact, leading to mass layoffs; the subsequent production ramp up has been (as they usually are) difficult, which may have led to quality issues. Not helping is Boeing putting severe cost pressures on their suppliers.

RE: Alaska Airlines flight forced to make an emergency landing...

And stop with the criticism of the NTSB. They are the most technically competent agency in the entire US government.

RE: Alaska Airlines flight forced to make an emergency landing...

Thx to Murph 9000's 11 Jan 24 22:31 post I finally understand the whole stop pad / pin thing, I'd now like to get a better understanding of how the pressure seal / gasket arrangement (internal / external) works, especially as related to the up /down, inboard / outboard movement of the door / plug. Must be some not so trivial "wiping" of the gasket. or so I suppose....

The problem with sloppy work is that the supply FAR EXCEEDS the demand

RE: Alaska Airlines flight forced to make an emergency landing...

I concur about the NTSB... my only criticism is the length of time involved in the preparation of their reports.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I'm starting wonder if the proximate cause was 4 missing bolts (2 in the tracks and 2 through the spring guides). This allowed to door to move upward and depart. The caveat is someone, based on a misunderstanding, overtightened the stop pins to arrest the movement of the door and keep it fixed. After time whatever was in compression around the frame creeped or shifted and the friction between the pin faces and the stop pads diminished to the point the springs could act on the door.
Just an uneducated theory because a cross section drawing of the door is unavailable.

The person may have used paint containers such as this:


These are clamps, not stop pads. Is it plausible someone mistook to door stop pins for clamps when in reality the plug is not meant to be clamped at all?

RE: Alaska Airlines flight forced to make an emergency landing...

All of you complaining about the “complexity” of the plug door design should see the complexity of the actual operable passenger doors. The plug door is relatively simple. And the basic configuration has to be convertible into an operable exit door.

The Max plug door design is likely the same as that used for the 737-900 (NG), which has been flying for many years. And similar plug doors have probably been used on other aircraft models.

As said before it seems highly likely the the 4 retainer bolts were not installed. One can speculate as to why, and it helps to understand how aircraft assembly factories operate. Highly choreographed, and if things get out of sequence, or rushed, or cycle time reduction pressures too high, or people are nit trained, escapes can happen. There is supposed to be robust quality oversight, but that gets viewed by mgmt as a “non value added” cost, so ………..

RE: Alaska Airlines flight forced to make an emergency landing...

Not knocking the NTSB as a whole, but given the circumstances and a lifetime of trouble shooting I do feel that this one sentence was ill advised, maybe only two words;
"But Homendy said she believes these three incidents are likely unrelated to the door plug blowout and that Alaska’s decision makes sense."
The engineers at the NTSB may be rolling their eyes at that statement.
Three alarms and then a blowout?
That's a huge red flag to a trouble shooter.
(Or has Boing's quality deteriorated to the point that frequent pressurization alarms are common?)
Three spurious back door alarms will ground a school bus.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

I have to agree with waross on this one. Though the NTSB has done some outstanding work, they are not infallible and are showing some troubling attitudes.

RE: Alaska Airlines flight forced to make an emergency landing...

Another possible solution for Alaskan.

Costs a little more, but worth it.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

more fallout...

"A class-action lawsuit was filed Thursday against aircraft manufacturer Boeing on behalf of multiple passengers who were aboard an Alaska Airlines flight last week that was forced to make an emergency landing in Portland, Oregon, after a portion of the fuselage blew out in midair.

The lawsuit — filed on behalf of six passengers and a relative in King County Superior Court in Washington state, where Boeing is headquartered — alleges that "the event physically injured some passengers and emotionally traumatized most if not all aboard."

On the night of Jan. 5, Alaska Airlines Flight 1282 was carrying 174 passengers and six crew members bound for Ontario, California, when a door plug of blew out just minutes after the Boeing 737 Max 9 had taken off from Portland."

https://www.cbsnews.com/news/boeing-alaska-airline...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

For those that have not seen this, the Boeing corporate takeover and subsequent demise of engineering QA/QC can be seen in the aptly named documentary "Downfall" (Netflix).
https://www.latimes.com/entertainment-arts/movies/...

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Is it possible that the springs were faulty or not there?

RE: Alaska Airlines flight forced to make an emergency landing...

If the springs were missing or weak, that would have helped to prevent the incident. The springs assist in opening the plug (and closing it), not keeping it closed. If the springs were too strong, it's highly unlikely that they would have been able to overcome 4 correctly fitted locking bolts.

RE: Alaska Airlines flight forced to make an emergency landing...

Do the people bitching about Alaska ignoring or not properly responding to the warnings not realize that Boeing documentation for the aircraft lists the inspections, repairs and actions that need to happen when the warning goes off? The airline aren't sold a plane and left to blindly figure out how to address any issues with the plane.

If there aren't enough inspection and repair steps after the warning before the plane can fly again then that is also squarely Boeings fault alone.

RE: Alaska Airlines flight forced to make an emergency landing...

The problem could be seen this way - Alaska had several of the same problem and the Boeing solution provided didn't work. Knowing that the solution didn't work, Alaska kept using the plane.

This was the same problem that Lion Air faced before they crashed - a serious number of AoA sensor failures they could not figure out on a relatively new plane. They finally replaced the sensor and immediately got another AoA sensor failure. And then put the plane back into service to crash the next day.

Alaska did not offer that they had found the root cause of the spurious warnings and it was corrected. They recognized the severity of the problem by removing the plane from ETOPS use.

RE: Alaska Airlines flight forced to make an emergency landing...

The ongoing cabin pressure warnings didn't require taking it out of ETOPS. As Juan Browne / blancolirio explained, ETOPS operation allows for loss of pressurisation and the increased fuel burn that would result from returning from mid-ocean at 10,000 feet.

Alaska most likely were operating in "abundance of caution" mode, combined with wanting to keep the plane near maintenance facilities until they figured out what was going on with it. Cabin pressurisation issues are serious, but have very well trained and planned contingencies that do not require grounding an aircraft and performing extraordinary investigation.

RE: Alaska Airlines flight forced to make an emergency landing...

It was required for Alaska's peace of mind or they would not have done it.

A serious problem on a new plane requires an extraordinary investigation. Did what happen seem like a reason to ground planes? Because everyone else does.

RE: Alaska Airlines flight forced to make an emergency landing...

Hindsight is 20/20. Yes, of course it was appropriate to ground them after the loss of the door plug, and I'm a little concerned that the EAD and grounding does not also apply to the 900ER with apparently the same door plugs.

As I understand it, prior to the incident, the plane was not actually losing pressurisation, it was just appearing to be a fault with the automatic pressurisation system. The system has a high level of redundancy, and the ultimate contingency of masks and rapid descent to 10,000. They were following the FAA and manufacturer rules in how they dealt with it.

RE: Alaska Airlines flight forced to make an emergency landing...

It's not hindsight. It's knowing from past industry experience how a severe problem can originate from a minor problem, as the Lion Air crash clearly showed.

Alaska owns a piece of this.

Would you rather this had been discovered before the accident, or is it better to have the accident happen?

RE: Alaska Airlines flight forced to make an emergency landing...

The pressurisation thing could indeed be red herring as it was apparently "solved" by switching computers. If there was a continued air leak, this would not have worked.

I'm pretty sure the 737s don't have an ECAM system for monitoring these things and telling pilots what the issue is and what the fix is so if the first action is try the other computer / monitoring system and the alarm goes away then there's not much record of it.

And intermittent faults are always a bitch to fix.

Having a large part of the aircraft depart in flight is indeed a reason to ground them. An alarm going off three times in 100 flights is not.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

The move to the backup gives time for the seal to be energized by the pressurization system, covering the fact that the seal may not be making initial good contact.

The pilots don't need diagnostic info - that info is available to the maintainers.

There are only a few things to check. Are the sensors working properly? Is the wiring complete? Is the reported problem a pressurization problem?

Rather than take it out of service to find the problem they gambled that it was not a real problem.

RE: Alaska Airlines flight forced to make an emergency landing...

Now if there had been passenger complaints about a whistling noise or air movement next to the plug door, I would grant you it's unreasonable not to suspect something is wrong. But unless they stripped the plane back to skin you would never find bolts missing from a plug door.

So I think this is all very secondary as we don't know what they did or how long it happened for or any real details.

I'm sure someone somewhere will stand in front of a lectern holding four bolts and ask people how much they are worth. In Boeings case $13.5 BILLION dollars.

That's some expensive bolt.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

I really do feel that it's unreasonable to expect Alaska to discover Boeing's failure here (assuming Boeing were the last to close the plug and fit the interior panelling over it). To me, it falls under the saying from the medical profession, "when you hear hoofbeats, think horses not zebras". Boeing/Spirit not properly assembling / securing the plug feels like a zebra to me, as far as dealing with the pressurisation system issues is concerned; I'm not convinced that it was reasonable for them to suspect a problem with the semi-permanently closed plug, based on the information and symptoms presented to them at the time.

RE: Alaska Airlines flight forced to make an emergency landing...

Just to throw this out there, it seems that the first assumption was that a leaking door may have caused the cabin air pressure faults. But, a faulty cabin air pressure system may also cause a high pressure condition that caused the door to fail. We have not heard any statements on whether the pressure was (or was being indicated as) high or low.

RE: Alaska Airlines flight forced to make an emergency landing...

There would not be air movement - it is covered by an insulated panel. Nor would it whistle. Having been seated next to an poorly sealed emergency door the main effect is that the external jet engine noise enters the cabin but, again, this involved a cover panel with insulation.

I guess anyone who ever notices their brakes aren't working should just operate the car as normal and blame the maker when there is a crash?

There should be clear evidence of what caused the pressure system fail indication. It doesn't matter if it's a Zebra. If the problem is that the plane is pressurizing too slowly that means there is a leak. Finding a leak is a common action. If the airline doesn't want to, contact Boeing and have them find it. At worst they do a smoke test to see where smoke exits.

I don't feel like, if I am plummeting through the air to my death, that the last thought would be "I hope the airline can shift blame to the maker for not dealing with a problem they knew about."

RE: Alaska Airlines flight forced to make an emergency landing...

3
"If..."

If that was happening then switching to a different control package would make no difference... And the fault would persist.

We're all making wild assumptions about something we know very little about. There are many causes behind a potential pressurisation fail - it may be lack of pressurising air from the engines, it might be more air going out the vents than is supposed to be, it might be a faulty transmitter, it might be a faulty control circuit, it might...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

737 don't have ECAM or a health monitoring unit.

There are independent pressurization protections for both ends of the envelope that don't involve human or computer input.

And waross Airbus isn't an option for a lot of airlines mainly because the order book is so full and delivery times so long.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Tug)

But, a faulty cabin air pressure system may also cause a high pressure condition that caused the door to fail.
The pressurized vessels I work with have pressure relief devices intended to prevent failure due to overpressure. Are they not present on aircraft?

RE: Alaska Airlines flight forced to make an emergency landing...

There are pressure reliefs in both directions, although for ground testing they can be locked. Forgetting that has had problematic results. Anti-vacuum valves to stop the fuselage becoming a crushed can and over-pressure reliefs to stop it bursting.

I'd rather fly an airline that had sufficient diagnostic ability to return full confidence than one that depends on drop-down masks to keep me safe from a detected problem that just hasn't gotten that bad yet.

Maybe switching to a different system isn't what made the difference. Maybe it just gave time for the pressure to push the seal back into place; maybe the warm interior air softened the seal some tiny amount while the pilots were playing wack-a-mole. The coincidence seems too on the nose.

RE: Alaska Airlines flight forced to make an emergency landing...

Alaska could have been a little more cautious, not knowing why the 'seal' failed or at least an error was registered. Because of the latent problem, Alaska would not likely be able to determine the source of the problem. In addition it is a little bit of a reach to anticipate the consequences of the problem caused by Boeing or Sprint. My $0.03CAN...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Wiki only discusses ETOPS in regard to limits for engine failure on a twin. I do not see where it is applicable to any other potential failure. Any reference showing that it is applicable to decompression? Distance limits are rediculous for decompression warnings. It must be an altitude limitation, or it makes absolutely no engineering sense. I find it difficult to believe that flying at 10,000 ft for 3 hours to land with a door blown out was ever contemplated as an approved emergency procedure. Are there any approved time to airport limitations under which an AC can fly in commercial service with a blown door/Hull failure. I'll eat my socks if its something other than "Descend to 10,000 ft and land at the nearest airport". Even if there were, would anyone be dumb enough to do it? This plane was apparently climbing to an altitude of at least 21,000 ft, but aborted that plan when it decompressed at 16,000. I do not know if an altitude higher than 21,000 was planned as its ultimate cruise altitude. But in any case, if an op limitation were to be made, it should have been "Nothing higher than 10,000ft".

If Alaska Air did not know that 3 warnings, 2 in the previous 2 days on a Max is not potentially very serious, well I guess they do now, and this is not going to be the end of that lesson. Anyway you look at it, unless you disagree with my calculation, 99.9994% is a sure thing something is WRONG with PRESSURE CONTROL. Not the engines. My opinion is that its just plain stupid to continue operating under any circumstances, made even worse by not understanding that a distance limitation was incorrect in the face of pressure problems. It's BASIC physics. If it's true that 3 warnings on one sensor group is not enough of a reason to "stop work", then tell me how many are enough for you. Where do you draw the line. Sure, Intermittent problems are difficult to fix, but that's why they get paid more than auto mechanics. ITS THEIR JOB! If they continue flying until they find the problem, (esp. After 3 warnings) what does that mean? It means they were testing with live guinea pigs. We clear the freeking area for a hydrostatic vessel test. We do not put 175 people on top of the thing when we do it. How difficult is it to do a soap bubble test around door and window frames?

IMO, Alaska owns this just as much as Boeing does. They know it too. They just have their spin doctors out trying to clean it up as much as possible and control the naritive. "Abundance of caution", OMG. They may fool the physics flunkies. I'm not buying it.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

A smoke machine would find the problem of a seal out of place; they used to use tobacco stains for smaller leaks. There are also ultrasound systems that can detect leaks if a smoke generator isn't suitable.

Seeing that all openings are actually secured isn't too big a stretch as would seeing if the doors are actually closed, something that is visible from the ground.

RE: Alaska Airlines flight forced to make an emergency landing...

Bucket of soapy water.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

But, a faulty cabin air pressure system may also cause a high pressure condition that caused the door to fail.
Given the hard evidence at hand, That statement sounds like it could come from a lawyer who studied with tRump's lawyers.

Quote:

Maybe switching to a different system isn't what made the difference. Maybe it just gave time for the pressure to push the seal back into place; maybe the warm interior air softened the seal some tiny amount while the pilots were playing wack-a-mole.
I suspect that that is exactly what happened.
The seal was imperfect and leaked at low differential pressure.
As the differential increased, the seal was force into place.
But the initial leak caused the alarm.
The switchover to the alternate system gave the extra few seconds for the differential pressure ti rise so that the seal stopped leaking.
I have seen similar effects inflating tires so as to seat the bead.
If the air going in is more than the air going out, then the bead will seat.
If the air going in is not enough volume to overcome the leak, then we go to plan B or plan C.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

2
Agree with 3DDave.

"We're all making wild assumptions about something we know very little about."

Yes, and a lot of "us" (you) are putting blame on Boeing before we know who really dropped the ball. It's as likely that Alaskan service crews pulled the plug out during some refit as it was for Boeing to do so.

To coin an idiot's overused phrase, "we'll have to wait and see".

RE: Alaska Airlines flight forced to make an emergency landing...

A refit of a plane not even 3 months old sounds a bit unlikely to me....

But agree, we don't know for sure who was the last company to refit the plug, however Boeing seen to be the most likely.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Given that loose hardware has been found on other planes, Boeing certainly has a problem.
Given that Alaska had repeated detections and kept the plane in service indicates Alaska has a different problem.

There have been plenty of warning flags waving that Spirit has been shipping defective parts and assemblies and Boeing has been dealing with them. Sorting out the finger pointing may take a while.

RE: Alaska Airlines flight forced to make an emergency landing...

The plane would have to be checked by maintenance personnel and passed the tests prescribed by Boeing before going back into service. I doubt they were "Hey, it went away, fuck it lets keep the plane flying."

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (LI)

A refit of a plane not even 3 months old sounds a bit unlikely to me....

In this post-pandemic world we are still swimming in backlogs. It's not uncommon to remove parts from assemblies on the production line to support off-line units. Or, reconfigure a product in production to shift to a higher priority customer.

RE: Alaska Airlines flight forced to make an emergency landing...

What's inside a Boeing 737 Emergency Exit Door? Link

RE: Alaska Airlines flight forced to make an emergency landing...

3

Quote (TugboatEng (Marine/Ocean) 13 Jan 24 04:18)



A disappointing post.

RE: Alaska Airlines flight forced to make an emergency landing...

5
Musk is in no position to throw stones from his glass house, given his misleading promotion of advanced driver assist as "autopilot" and "full self driving". His dishonest and reckless marketing continues to encourage irresponsible use of his products on the public highways.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (IMO, Alaska owns this just as much as Boeing does.)


I'm pretty sure, not as much... maybe 5% to 10% of it. The problem was obscured and could not be determined without excessive 'dismantling'. The earlier flights indicated that it may not have been so serious.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I guess it takes one to know one. I remember a Tesla eviscerating itself and driver on a divider in autopilot on highway 280 which was right in Musk's backyard. Other drivers were able to recreate the scenario which was very interesting. Clearly a fault of the automation. No word from Tesla.

The comments on the story are interesting. Boeing farmed out production of the fuselage to Spirit so their corporate rules maybe don't apply. In that case my post above may not be relevant.

RE: Alaska Airlines flight forced to make an emergency landing...

DEI has no bearing on the failure of the 737 plug door. If that belief is strongly supported by this community of engineering professionals then the xenophobia is endemic and that situation is sad. I see this nonsense in comments on many other news threads and it is disappointing to see it even broached here. I have to shake my head and accept everyone has their opinion even if it makes no sense and their statements perpetuate falsehoods. Unfortunately, Elon Musk is Elon Musk.

RE: Alaska Airlines flight forced to make an emergency landing...

I specifically stated that this policy would not have had time to have been an influencing factor on this failure but will likely have an influence on quality in the future.

RE: Alaska Airlines flight forced to make an emergency landing...

Boeing didn’t “farm out” the fuselage fab to Spirit. 737 fuselages have always been made in the Wichita plant, which was a Boeing plant until about 2004 when Boeing spun off the Wichita commercial facility to create Spirit.

RE: Alaska Airlines flight forced to make an emergency landing...

Brian... DEI success occurs when you no longer recognise groups and the society is all as one.

One of my classmates from 60 years back (grade school) was Chinese... I knew him, and his family well. He would eat at our place and I at his... there was never a thought about him being Chinese. He was simply a friend. It was only a few years back that this was brought to my attention that he was Chinese.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I'm not well versed on the corporate side or things. When I said farmed out I meant transfered to holdings groups. The key is that the owning corporation can apply different rules to different divisions to bypass unions, regulations, governance policies.

Dik, your story is contrary to DEI success.

RE: Alaska Airlines flight forced to make an emergency landing...

The history of Spirt seems to be missed by most.

There are several other now suppliers providing core systems which the same was done to.

There was talk of Airbus doing the same with Hawarden after Brexit, but they decided not to.

The ETOPs stuff is strange and its an additional qualification for pilots. With out it we are limited to 1 hour single engine from diversion airport. There is additional equipment on board and servicing required. Burt quite what I have have no idea, the pilot stuff eg fuel planning I have no clue about because I have never been ETOPs qualified. But from the basic stuff from ground school I don't remember the depressurisation being included its not for none ETOPs fuel planning.

Depressurisation is covered a lot but related to terrain clearance and being able to descend to 10k.

I think the ETOPs is a statistical concept to reduce the risk below a certain fatality rate using historical data.

Depressurisation would effect a tri or quad engine aircraft in the same way as a twin which is maybe why its not included.

RE: Alaska Airlines flight forced to make an emergency landing...

2

Quote (dik)

Brian... DEI success occurs when you no longer recognise groups and the society is all as one

I agree with treating everyone respectfully and recognizing their skills regardless of color or creed. The nonsense of claiming DEI policies or programs making products or processes lower quality or dangerous comes up again and again in comments. That ugliness was thrown about with the FIU overpass tragedy (Denney Pate), the Titan submersible tragedy (Stockton Rush), Boeing 737 MCAS (Dennis Muilenburg and Kevin McAllister) and now it is being bandied about for the Boeing 737 plug door failure (Dave Calhoun).

Denney Pate, highly lauded and recognized bridge engineer, Stockton Rush, aeronautics engineer, both let their ego-focused goals blur their sensibilities. Muilenburg and McAllister are highly degreed aeronautics engineers with years of experience and worked their way up through the industry, real insiders yet they either mandated changes at Boeing to meet financial goals and promises and got caught flat-footed with the MCAS failure or they were overconfident of their previous successes and chose to allow shortcuts to be taken. The failure of MCAS was not driven by any DEI hiring policy - it was the guidance from the head offices was flawed.

https://link.springer.com/article/10.1007/s11948-0...

Dave Calhoun said he would change the management message after taking over the Boeing CEO position and maybe he has, maybe he hasn't but he and his team will be scrutinized through this plug door failure.

This claimed DEI poison gets put out there before a root cause has been determined and strikingly, in almost every case cited - the failure or tragedy was lead, controlled and/or designed by a well-degreed, generally well-respected, highly capable middle-age white male. I am not pointing out 'white male' to vilify them, I am pointing it out because those that claim DEI is the root of engineering failure miss the elephant in the living room. The failure mode generally has been a combination of additive failures in the design or system and some level of ego-driven blindness by the principal engineer. Quality and safety haven't been compromised because DEI policies possibly changing the cultural mix of the staff or workers or creating less capable people/staff. The failure or lapse of quality have occurred because either symptoms were ignored or disregarded, or financial pressures or motivations lead to decisions that proved bad.


Good points have been noted on the plug door, its retention fasteners, and the airplane pressurization sensors and warning system. At this point, I don't think it has been definitively determined if the four (4) lock bolts were not installed (though almost certainly they were not in place), or which party left them uninstalled (Boeing, Spirit, Alaska Airlines). The airplane pressurization system warning more than likely was related to the improper closure of the improperly retained plug door but with the plug door covered with an insulated interior panel would it be obvious the plug was the leak point? For a system the size of a commercial airliner how does a maintenance team track down a pressure fault? Maybe the altitude restriction step taken by Alaska until the pressurization fault could be determined is not unusual or reckless to those in the industry? Certainly, in 20/20 hindsight it seems less than perfect.

Then Elon Musk weighs in with his opinion and as the world's richest man, he obviously must know something, and all the Musk sycophants get repeating the same bad belief. He is a very successful business man and has done some things very well and others poorly. I am not a rabid supporter of mandatory DEI but for me Elon Musk's DEI statements show he is missing the engineering truth and has a weakness of character.

RE: Alaska Airlines flight forced to make an emergency landing...

No altitude restriction has been mentioned; only distance based on time of flight.

I would think that leaks would not be so hard to find. There are points where the probability of finding them is 100x others. We check the bolted flanges first. Easy to say in hindsight, but doors and door plugs would be #1 on my list. Get a bucket of superbubble mix and have at it, or download Spectroid app to your phone and get a waterfall plot of the sonic environment. It's quite sensitive . I can see the frequency of a bee beating its wings.

But yes. There apparently are altitude restrictions on where one can fly. Commercial aircraft with any number of engines do not venture into the Himalayas and some areas in South America (others?) that make it impossible to descend to and hold 10,000 ft and still reach an acceptable landing runway. No distance or flying time provisions are prescribed that I've seen, but I would assume there would be some judgement calls about what a reasonable time might be, if one had to descend into a valley and take a long circuitous route around a high ridge. There are probably a few of those in Colombia. The Andes split into three ranges making two deep valleys between them. Even if passes existed, the weather tends to be uncooperative and runways few. You might have to exit to the north coast landing at Cartagena or Baranquilla.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

1503-44

yes, you are correct Alaska Airlines did not put in an altitude restriction, it put in place a restriction of no long routes to Hawaii placing the plane over ocean water, thus allowing the plane to return to an airport if the pressure warnings returned.

RE: Alaska Airlines flight forced to make an emergency landing...

Right. That's what I have been ranting about. It's entirely the wrong limitation for decompression trouble. Decompression at 35,000 ft directly over JFK would have saved nobody. Alaska Air was very, very LUCKY. Only their passengers were luckier still. They should all go out and buy LottoMillion tickets.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

1503-44

Are you describing actual steps used by commercial airliner maintenance crews? Or are you stating techniques you have used for general pressure vessel troubleshooting? I work with pressure lines and containers in my industry but this is for benchtop medical/laboratory devices. I hardly believe my tools and techniques would work efficiently for diagnosis of an airliner.

RE: Alaska Airlines flight forced to make an emergency landing...

Download Spectroid. It will find your leak, big or small. If aviation tech doesn't know about ultrasonic leak finding or soap bubble tech I'm sticking to trains. It's a 2h flight to the mainland, or a 3day boat ride, so I probably won't be leaving very often,



The pulses at 8000 Hz is me bearly hissing heard over the lower freq noise of a passing car 30m away.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Interesting app - thanks!

RE: Alaska Airlines flight forced to make an emergency landing...

Welcome. In a quiet night env, it hears everything. What the neighbors are up to, or ocean waves 1.5 km away. I like seeing the Droppler effect of the cars and helicopters going by. Bees come in at 275Hz, house flies at 400+.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (1503-44)

Right. That's what I have been ranting about. It's entirely the wrong limitation for decompression trouble. Decompression at 35,000 ft directly over JFK would have saved nobody. Alaska Air was very, very LUCKY. Only their passengers were luckier still. They should all go out and buy LottoMillion tickets.

What is your basis for that assertion? Pilots don't suffer from an immediate loss of consciousness at FL350 in the event of loss of cabin pressurisation. It's serious, certainly, but they have training to respond to it and know it's critical to get their oxygen masks on immediately. See the FAA Pilot’s Handbook of Aeronautical Knowledge Chapter 17: Aeromedical Factors, page 17-4. They have 30 to 60 seconds of useful consciousness at 35,000 feet, which is sufficient time for the pilots to get their masks on.

Passengers might not fare as well due to lack of training, but it would likely still be survivable for most, even if they failed to don oxygen masks in time. The aircraft would be down at 10,000 feet, where masks are no longer required, within 3 to 4 minutes.

I stopped digging around for a specific incident after finding this one, as it's close enough. Southwest Airlines Flight 1380, a 737-700, experienced uncontained engine failure above 32,000 feet, followed by rapid decompression caused by loss of a window and some other holes in the fuselage from shrapnel. Sadly, there was one fatality, but other than that only minor injuries. They successfully flew a significant distance on one engine after rapid depressurisation and rapid descent.

NTSB Investigation and report: Left Engine Failure and Subsequent Depressurization, Southwest Airlines Flight 1380, Boeing 737-7H4, N772SW

It's reasonably likely that Alaska's MAX 9 would have fared no worse than SWA1380 if it had lost the plug at 35,000 feet.

Edit - prior threads on SWA1380:

thread815-437955: Southwest Airlines flight experiences engine explosion but makes a safe landing in Philadelphia...
thread815-460717: 2018 Southwest Airlines Flight 1380 Uncontained Engine Failure

RE: Alaska Airlines flight forced to make an emergency landing...

So, let's just go to 40,000, 50,000? The details are unimportant. I'm not interested in discussing survivability. This is not an X-15 test flight. This is an EXTREMELY UNDERDESIREABLE EXPERIENCE, even if to happens at 100 ft.

So, you are pretty much saying, even if you know the plug blows on this flight, you're going to board and blowing out at 35,000 is perfectly fine for you. Fine. Seat halfway down on the left. I don't like the probability. In my book it's a sure thing, or closer than I'd ever want to get to it, and I'm not boarding. It's not MS Flight Sim.

Its 2024. We been to the Moon 55 years ago. Its 2024 and if I can find a leak with my phone, Alaska and Boeing need a better SOP. Live guinea pigs flights is not the answer to an immenent decompression, even if they limited altitude to 10,000 ft. 3 warnings is a sure thing. Any maintenance tech knows it and trusting passengers deserve better. End of story.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

No, what I'm saying is that you are wrong in your assertion that "Decompression at 35,000 ft directly over JFK would have saved nobody." It's a planned emergency that every airline pilot trains for, and should generally be survivable. The 737 NG & MAX series have a maximum operating altitude of 41,000 feet; it's also probably survivable at that altitude.

RE: Alaska Airlines flight forced to make an emergency landing...

What I'm saying is "so what?".
A probability of 1 of having a decompression emergency is completely unacceptable.
Remembering that training is not guaranteed to give successful results in actual events and that even actual events can not be simulated in training situations. Fear factor for 1.
Whether it is survivable or not is totally irrelevant.
Several potentially deadly mistakes were made.
All Unacceptable.

But yes, I will agree this one was as good as a "planned emergency".
Couldn't have said it better myself.



--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Brian, I see a lot of complaints about prioritizing profit for shareholders contributing to these problems. That's ok to talk about. The loss of talent following the McD takeover, that's ok to talk about. The rapid adoption of DEI is the NEXT problem. That's not ok to talk about for whatever reason.

RE: Alaska Airlines flight forced to make an emergency landing...

Is that ever a neat app... It likely would have found the 'leak'.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I might believe DEI, if Boeing had hired DRI-type inspectors. The problem is that (according to the documentary film) most of the inspectors were let go, whistle blowers fired, etc. Etc. and NOBODY took their place. Not even illegal aliens.

Is there traceable evidence DEI policy is at fault?
OK. Let's see it.


--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Tugboat, I am not saying talking about DEI is not okay. I am saying claiming DEI policy has caused or may caused a loss of quality or safety is false. Sitting around bench racing, any number of items can be claimed but when most engineering failures are examined, the fault was not the color, creed, sex or orientation of the designer or team. When the root cause(s) of this plug door issue is fully understood I will be highly surprised and corrected if any factor is found that is DEI driven. As previously stated, I am not a fervent supporter of all DEI policy, but I strongly disagree with anyone claiming it is creating quality or safety failures.

RE: Alaska Airlines flight forced to make an emergency landing...

Yeah Dik. Turn the gas stove or fireplace on so low you can't hear it. Check the sensitivity.
I bearly cracked the needle valve of bottle of butane under my torch nozzle, bottom right 3 bars and slowly closed it until I couldn't hear it at all after the lines got lighter, yet it still registered until I turned it the last 5° or so and it cut off entirely.




--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (1503)

Is there traceable evidence DEI policy is at fault?
OK. Let's see it.

I did post a link to Boeing's job application site that touted its recent DEI achievements but the post was removed.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (The nonsense of claiming DEI policies or programs making products or processes lower quality or dangerous comes up again and again in comments.)


The point I was trying to make was that in a proper environment DEI would not exist. It's presence only prolongs a much bigger problem.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Turn the gas stove or fireplace on so low you can't hear it. Check the sensitivity.)


Checked it with a light breath... even the faintest one registers 'bigly'. Have to experiment to see if it can record heartbeat and pulse, or maybe be used to a stethascope (sp?).

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I revised the foto above for a faint gas flow from a torch. I could not hear it at all at cutoff.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

financial pressures or motivations lead to decisions that proved bad.
Unfortunately I feel that this describes all of Boing's corporate decisions.
Let's reward customer safety success. Is this about safety or about financial pressures?
Not getting the bottom line results that were expected?
Let's try DEI. Is this about social responsibility or about financial pressures?
Not getting the bottom line results that ere expected?
Let's try......

Does Boing have a fatal problem?
MCAS?
Was this an isolated problem to be solved or a symptom of a much more serious problem?
Debris left in the tanks?
Was this an isolated problem to be solved or a symptom of a much more serious problem?
Loose bolts in the rudder assembly?
Was this an isolated problem to be solved or a symptom of a much more serious problem?
Failure to install the locking bolts in the door plug?
Was this an isolated problem to be solved or a symptom of a much more serious problem?
The discovery of other loose bolts in the door hardware?
Was this an isolated problem to be solved or a symptom of a much more serious problem?

Is it time for the FAA to take a step back and look at the overall picture?
Is Boing no longer capable of building safe aircraft?

I expect a slew of negative responses.
I may save them for a big "I told you so" when the next Boing fiasco materializes. It may be in months, it may be in years, but under present ownership, it is inevitable.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Tugboat)


I did post a link to Boeing's job application site that touted its recent DEI achievements but the post was removed.

How is a job application posting that mentions DEI acheivements evidence for showing DEI policy has directly lead to bad engineering or is causing quality or safety failures?

Show documented proof of a DEI hire that through their actions/non-actions caused an engineering failure.

RE: Alaska Airlines flight forced to make an emergency landing...

DEI evidence needs to be traceable to an incident of at least some negative consequence to be considered as a negative effect. The policy itself probably does have at least some beneficial accomplishments. The other problem is credibility of the sources of the complaints. I see bad work from ... everywhere. Inexperience and failure to recognize situational dangers being the biggest culprits. People just don't realize the water's getting high until their car floats off the freeking road into the culvert, so to speak. And that applies to everybody, all colors, all races, all levels of education and financial capability, myself included. All of a sudden, its chequemate. People just refuse to recognize that they're in over their heads for whatever reason. Falling off a cliff while taking a selfie, etc, etc.


--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

The root of Boing's issues.
The blue collar workers and the engineers are directed by lower level managers.
Those managers respond to higher level managers or they are no longer managers.
This goes up the food chain until we reach the CEO and the CFO. They respond to the board of directors, or they are gone.
The board of directors are selected by the owners, probably large fund managers.
It may be quite difficult to explain to the owners of a company that what the company needs is different owners.
What will eventually happen?
Will passengers start to avoid Boing planes to the extent that airline stop buying them?
Will fines and lawsuits become so onerous as to threaten Boing's Survival.

If you doubt the effect of ownership priorities on the performance of a company, look at
eX-twitter.
Am I over reacting?
If someone had over-reacted sooner, possibly the plug would not have blown off.
And, if someone had over-reacted sooner, possibly there would not have been more loose bolts to discover.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Brian Malone)

I am saying claiming DEI policy has caused or may caused a loss of quality or safety is false.

Whilst it’s speculative whether it played a role here, it is not “false” to say that DEI initiatives can affect quality. Diversity hiring is what it is.

RE: Alaska Airlines flight forced to make an emergency landing...

DEI?
The implementation of DEI?
Speculation about the effect of DEI?
Just red herrings to divert attention from a serious corporate cancer.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Throw it on the wall and see if it sticks.

I've lived and worked in as diverse as you can get for 30 years. Some companies with 75 different nationalities and languages, of which I was and remain only one. It's been difficult at times, but all efforts I have been involved with did not suffer from their diversity. Arrogance was the worst contributor of all.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

More scrutiny?

"The head of the Federal Aviation Administration (FAA) said he believed there were "significant problems" with the 737-9 Max jet as well as "other manufacturing problems".

The FAA said it would conduct an audit of the plane's production line.

It also plans to review who is in charge of quality oversight.

For years, the FAA has delegated some parts of quality reviewing of planes to Boeing, but the practice has been controversial, drawing repeated warnings of safety risks.

"It is time to re-examine the delegation of authority and assess any associated safety risks," FAA administrator Mike Whitaker said in a statement.

"The grounding of the 737-9 and the multiple production-related issues identified in recent years require us to look at every option to reduce risk. The FAA is exploring the use of an independent third party to oversee Boeing's inspections and its quality system.""

https://www.bbc.com/news/business-67960717

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

another 737... maybe not a very 'lucky' aircraft...

https://www.bbc.com/news/world-asia-67968526

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Waross)

Just red herrings to divert attention from a serious corporate cancer.

Regardless of whether it can be attributed to DEI, Boeing's integration of DEI and Climate into its primary corporate goals, alongside safety, during a period of fatal safety crises, is worrying. Why are they shifting corporate focus to diversity and climate when their planes are falling out of the sky?

RE: Alaska Airlines flight forced to make an emergency landing...

Can't argue with that Tom. Probably have seen some good benefits to corporate objectives. But they have lost focus on design and safety. That's for sure.

OMG No. Bad timing.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

MCAS became a problem because automation eroded basic piloting skills in a way that wasn't measurable. More automation made operations safer faster than poor skills made them less safe.

AF 447 gave the first clue as to how bad this was going to be. PIA 8303 made this erosion abundantly clear, but a comparison of what was recorded in the three flight FDRs vs. what pilots were expected to do showed just how bad this situation was on the accident flights.

The criminal factor was, having seen that this erosion had taken place at Lion Air, ET302 was dispatched without dealing with it, and then the resulting crash was misrepresented as pilots doing every step in the correct order at the correct time, when not one step taken by the ET302 crew was correct. Ever. As soon as the first automation problem happened, the stall warning, the crew failed to turn off the autopilot and the autothrottle; Day 1 items on stall warning response and both pilots failed. When the autopilot did disconnect the first and only order of business of both pilots was to try to force it back on and they continued to do that, stick shaking and alarm blaring, all the way to the ground.

ET302 could have been dispatched with the trim disabled; let the first officer row the boat as the PIC requests. No chance at all for MCAS to operate. But that would mean that the autopilot could not function. They were clearly terrified to fly without the autopilot.
---
As to the factory floor issues - maybe it's a similar thing. The expected performance of the workers is based on a standard from some time ago and the workers just aren't up to it anymore. There seems to be an America problem when middle class annual incomes used to be 50% of the price of a home and have dropped to 10% because of housing inflation. When a CEO made 20X the median salary in the past and now makes over 300X ** the median salary. It's not clear the workers are fundamentally less capable, just that the sense of accomplishment at producing huge profits for billionaires just doesn't motivate like applying craftsmanship to something they are rewarded for producing.
---
It's not just Boeing ownership. It's the American way of life that has significantly changed, mostly having to do with regulatory capture of the Congress and the White House that have shifted tax laws to make draining the life-blood of companies and their workers towards stockholders and CEOs possible. When Boeing was growing the top tax rate was probably 90% or so, but the tax laws gave breaks to investing in factories. Now every scrap of productivity is taken to the investors as profit and the workers are told to like it or leave. They cannot easily leave because the health care industry has also worked it's magic so that any minor issue could cost $10k - $1M to be treated and the price for individual medical coverage makes it difficult or impossible for 60% of Americans.

Boeing isn't a problem. Boeing is a symptom and a warning flag. Look at the railroads that fight active controls that would have stopped the derailment last year and fight adding hotbox detection systems. They succeed because they have bought the allegiance of lawmakers. Is it their fault for trying or for lawmakers accepting?

**Think of that. A CEO takes home in one year what a mid-level worker would take three centuries to match.

RE: Alaska Airlines flight forced to make an emergency landing...

dik,

Cockpit windows on airliners cracking happens with some regularity. There are huge thermal differentials between the inside and the outside with defrost heaters on the inside producing large tension loads in the outer panes of glass. A tiny scratch can be enough to initiate a crack.

See https://www.reddit.com/r/SweatyPalms/comments/8lho... (from 2018)and read the comments. It's not normal, but it isn't particularly dangerous. Oh, apparently the aircraft was an Airbus A319.

https://www.reuters.com/article/us-china-airplane/...

RE: Alaska Airlines flight forced to make an emergency landing...

Is it their fault for trying or for lawmakers accepting?

Both have lost their ethical standards and there is no disadvantage to pursuing profit at any cost.
They take the hit and stock price rises. They get bailouts and stock price rises. Insurance pays out. Insurance is tax deductible. Public pays for higher insurance rates. Limited competition ensures product demand. No downside anywhere.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

I have no expertise or authority to speak about piloting so I am going use the statements by Capt. Sullenberger from the article I linked in my 1/13/24 8:09 post:
------------
Others have taken a more critical view of MCAS, Boeing, and the FAA. These critics prominently include Captain Chesley “Sully” Sullenberger, who famously crash-landed an A320 in the Hudson River after bird strikes had knocked out both of the plane’s engines. Sullenberger responded directly to Langewiesche in a letter to the Editor:

… Langewiesche draws the conclusion that the pilots are primarily to blame for the fatal crashes of Lion Air 610 and Ethiopian 302. In resurrecting this age-old aviation canard, Langewiesche minimizes the fatal design flaws and certification failures that precipitated those tragedies, and still pose a threat to the flying public. I have long stated, as he does note, that pilots must be capable of absolute mastery of the aircraft and the situation at all times, a concept pilots call airmanship. Inadequate pilot training and insufficient pilot experience are problems worldwide, but they do not excuse the fatally flawed design of the Maneuvering Characteristics Augmentation System (MCAS) that was a death trap.... (Sullenberger 2019)

Noting that he is one of the few pilots to have encountered both accident sequences in a 737 MAX simulator, Sullenberger continued:

These emergencies did not present as a classic runaway stabilizer problem, but initially as ambiguous unreliable airspeed and altitude situations, masking MCAS. The MCAS design should never have been approved, not by Boeing, and not by the Federal Aviation Administration (FAA)…. (Sullenberger 2019)

In June 2019, Sullenberger noted in Congressional Testimony that “These crashes are demonstrable evidence that our current system of aircraft design and certification has failed us. These accidents should never have happened” (Benning and DiFurio 2019).
-------------

Sullenberger is a renowned pilot of some skill and I interpret his statements to be it is wrong to attribute the 2018 and 2019 crashes totally on pilot error/inexperience, the MCAS system caused the presentation of the flight situation to be different than the actual conditions and MCAS was the fault for making the 737 Max airplane a "death trap".

RE: Alaska Airlines flight forced to make an emergency landing...

I have had 3 windows crack

One on a Q400, and 2 on Jetstream.

They have 10 plus laminates.

Only scary one was when the window heating started arcing

RE: Alaska Airlines flight forced to make an emergency landing...

Sullenberger should have talked to the pilots of the first flight and observed what the experienced pilot of the second flight did and commented that the Ethiopians had 100% knowledge of "how it presents."

I have no idea how Sullenberger came to be in that position, except that he was lied to by the original reports on ET-302 and believed them and was never called upon to justify his position when so much money from lawsuits against Boeing was available. It wasn't until 2020 that the Ethiopian FDR was released to show the gross mishandling of the plane, so any 2019 testimony was based on hear-say from the Ethiopians.

Note that Sullenberger kept his mouth entirely shut after the Lion Air crash preliminary report. Didn't say a word. If he was so smart as to identify that MCAS was an inescapable problem, which the first Lion Air incident showed by their 90 minute flight to a safe landing, that is was easily escapable by pilots uninformed about how it worked, then why didn't he say anything?

All that Sullenberger did that was great was deciding to make a water landing rather than try for a runway. That is, he didn't do something stupid.

The emphasis on trim runaway is a lie, baked in a fallacy. Every pitch trim problem will stop when the trim drive hits the trim stops and therefore cannot runaway. He never said how long it would be observed before declaring a trim runaway, but in the accidents it took a trim time of around 30 seconds before the plane became too tough to muscle. At 9 seconds the trim load was getting over 20 pounds vs. the typical thumb and index-finger pressure required. What feedback should a pilot have that trim is a problem? Offsetting that trim force required the use of a thumb.

Sullenberger had 30 years or so to complain that the trim runaway criteria were too vague. He didn't say anything. As far as I know he has never said how trim runaway should be diagnosed. He holds it up as a red herring to distract that the pilots on ET302 went 100% the wrong way on both the stall warning and then MCAS inputs after the way to successfully diagnose and respond was published following Lion Air.

RE: Alaska Airlines flight forced to make an emergency landing...

Worker productivity or competence?
A Texas based company bought into a northern Canada oils sands facility.
They sent some Texas hotshot engineers up north to oversee.
One drop-in questioned some temporary hoarding.
That is protect pumps from the cold.

"Get rid of that mess.
We don't need it.
We get winter in Texas too."
The next cold snap, the plant was shut down by the cold for the first time in its 30 year history.

For years, the standard response to an questionable suggestion?
"Ya. We get winter in Texas too."
Rinse and repeat.
Some years later, I participated in a maintenance shut-down at the same plant.
The shut-down was planned for 6 days.
A hot-shot drop-in from Texas arbitrarily shortened the 6 day shut-down to 5 days.
The result:
A safety shut-down system was completely rewired.
About 1000 feet of cable and many junctions and connections.
Testing and commissioning?
That was day six and never happened.
Did the safety system work as intended?
Who knows.
We won't find out unless there is a critical failure to operate.
Some work was done on a 3000 HP wound rotor motor.
The motor failed to start.
The brushes were removed and were originally scheduled to be replaced on the 6th day.
There was no 6th day.
But trouble shooting and repair was now out of a different budget.
It doesn't matter how competent or responsible a worker is, if a job takes 6 days and the manager reassigns the worker to another task on day six, you get the idea of how management may impact quality.
DEI at Boing?
PR
By the way,

Quote:

Houston has been keeping a record of its temperatures since 1921. During the first decade of record-keeping, Houston recorded its historical lowest low. This occurred on January 18, 1930, and the temperature was 5 degrees Fahrenheit.
The temperature at that plant right now is minus 47 F with a wind chill of minus 60 F.
But "We get winter in Texas too."

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

From slashdot today

WSJ: Boeing's Fuselage Factory 'Plagued' by Production Problems and Quality Lapses

US Regulator Considers Stripping Boeing's Right To Self-Inspect Planes


Quote (Attached Letter from Maria Cantwell United States Senator, to FAA Administrator Administrator Whitaker:)

... Specifically regarding Spirit AeroSystems, please provide the Committee with an explanation of FAA’s oversight of Spirit’s production system and of FAA’s oversight of Boeing’s supplier control system as it relates to Spirit. Please identify what, if any, improvements in oversight by FAA that you intend to implement to ensure that Spirit’s future performance meets all FAA regulatory requirements. ...

This will get painful. Ignoring quality, just like ignoring worker safety eventually hits the bottom line. thumbsdown

RE: Alaska Airlines flight forced to make an emergency landing...

The removal of self inspect will solve the issue.

Unfortunately I don't think they can claim back the bonuses which created this issue.

RE: Alaska Airlines flight forced to make an emergency landing...

Cantwell should know.

Quote:

Cantwell is a longtime Boeing advocate who supported the FAA Reauthorization Act of 2018 that changed the certification process to allow for more delegation of regulatory oversight to Boeing and other manufacturers.

Boeing employees collectively contributed nearly $62,000 to her reelection bids since 2015, according to opensecrets.org. A spokeswoman said Cantwell doesn’t take money from corporate political action committees.

Cantwell wrote a key amendment that gave Boeing and other companies authority for approving anything deemed a “low and medium risk” during airplane certification.

https://www.columbian.com/news/2020/jan/21/cantwel...

RE: Alaska Airlines flight forced to make an emergency landing...

Thanks 3DD and Alistair... I wasn't aware of that.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

In some small attempt at fairness, Houston was one entire week below freezing 24/7 in the winter of 1984/5, which killed thousands of fish in Galveston Bay and surrounding water's, and from 1960 to 1990, it froze about every 2 years and snowed maybe once every 5 years, once not melting in an entire day. But I agree that you shouldn't take a Texan's word about anything below 32°F, including LNG piping, especially how to drive on ice, or in rain, except maybe if it involves O-rings, but actually that guy probably was an immigrant, maybe NASA's first DEI employee? 😀

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

New information regarding Boeing and Spirit... from blancolirio. I don't know if this has been posted.

https://www.youtube.com/watch?v=RSGujNq4bVM

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Apparently the FAA is looking at the whole problem and not just at the plug blowout.
Bad news for Boing, good news for the flying public.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Many here think the FAA blew it during the MCAS investigation. Is there any reason we should think this new one would be different?

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (A Texas based company bought into a northern Canada oils sands facility.
They sent some Texas hotshot engineers up north to oversee.)


I've only ever met two Texans... they were 'pushers' for a sawmill project I did in Northern Ontario, and they were pretty good. This was back when Clinton was president...

I casually asked them if it was true that Clinton was going to cut Alaska in half, and make Texas the third largest state. The one guy's response was, "There's nothing that a**hole could do that would surprise me."

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (All that Sullenberger did that was great was deciding to make a water landing rather than try for a runway.)


I thought the pilot of the Gimli Glider was better...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

The turning the APU on outside the emergency checklist made a huge difference.

Meant they didn't loose power and the aircraft stayed in Normal law with flight envelope protections.

It is likely they would have stalled at some point if they hadn't had the protections, which would have changed the outcome.

And he isn't a normal pilot. He was a sim examiner for years and also an accident investigator.

I suspect his political leanings come into play with some of the talk about him in both directions.

My personal opinion is that he is neither the spawn of Satan or has golden bollocks.

Gimili glider apart from the initial screw up with metric/imperial fuel loading, definitely leans towards golden bollocks on the handling skills.

RE: Alaska Airlines flight forced to make an emergency landing...

I've raced my Cooper on that tarmac...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

2
Sully, the Gimli crew, SWA1380, the Alaska pilots here, the Speedbird 747 that lost all 4 engines; they all kept their cool in a bad situation, followed their instincts and training, exhibited commendable airmanship, and (most importantly of all) pulled off a very successful outcome from situations that could have ended far worse. They all deserve praise, a bottle of whisky, or whatever.

RE: Alaska Airlines flight forced to make an emergency landing...

Aloha Airlines Flight 243 also fits the category of successful management of flight operations outside of the training envelope.

Quote (http://avstop.com/stories/aloha.html)

Aloha Airlines Flight 243 departed Hilo en route to Honolulu at 1.25 p.m. on 28 April 1988. As the Boeing 737 leveled off at top of its climb the fuselage ruptured and senior flight attendant Clarabelle Lansing was blown from the aircraft. To her death.
Aloha Airlines Flight 243, Wikapedia
NTSB Report Link.
Page 64 has some interesting observations about the FAA evaluation of PMI's performance. Are these same problems still existing?

RE: Alaska Airlines flight forced to make an emergency landing...

LPS for Murph. Its easy to point toward intense training regimens and minimize these crews as having simply done their jobs, but that's not fair IMHO, even if humble crewmembers agree with it. Its impossible to predict how even the most highly-trained professionals will react to a life-threatening situation until the bullets suddenly start flying, the building is on-fire, aircraft fails, etc. Some will freeze, some will panic, some will do their job. Kudos to the ones who keep on keeping-on.

RE: Alaska Airlines flight forced to make an emergency landing...

To the hall of champions, add Richard Champion de Crespigny, pilot of the Qantas QF32 A380 which suffered uncontrolled engine failure shortly after departure from Singapore in 2010.

RE: Alaska Airlines flight forced to make an emergency landing...

The volcanic ash event on a 747 when all 4 engines shutdown was another one as Murph mentions.

There is a don't give up criteria in sim sessions and tests.

They went to far with it after the sims became more realistic and it started creating mental health issues. So they are not meant to create you will crash and die we just want to see you not give up until the bitter end which was happening.

see they have already upgraded the sims.


RE: Alaska Airlines flight forced to make an emergency landing...

Brutal!

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

fish2

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

It's Replacement Theory and it is based on ignoring that many American jobs have been replaced by citizens of India, China, Taiwan, Japan, Thailand, Vietnam, Mexico ... doing those jobs, but the local replacements are all supposed to be completely inferior in every way.

RE: Alaska Airlines flight forced to make an emergency landing...

Yeah. I need a red herring without the "?"

Looking at the actual Boeing-FAA recent historic evidence I'm more inclined to believe their inbreeding was what got them into trouble and that a massive dose of fresh blood DNA might be just the thing they need. Seems like their press releases say both are taking that perspective. Pack some mRNA in there and it could be a big winner. Whatever policy they had before sure tanked.

In fact, this is not something new. If it wasn't for German DNA injected into the early rocket programs, the Russians would have solved all our current problems for us a long time ago.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

What will people with "severe intellectual disabilities" contribute to the FAA?

RE: Alaska Airlines flight forced to make an emergency landing...

Its a good thread, please don't spoil it with political stuff.

RE: Alaska Airlines flight forced to make an emergency landing...

Typical deflection from the issue.

They have at least taken ownership, but has Boeing actually said "sorry" about this incident?
I haven't seen it yet. Hopefully they have.



--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

I wouldn't call it an apology.... but its better than blaming the pilots which was what they have previously done for pretty much everything.

(To be fair most of the time it is the pilots..)

https://edition.cnn.com/2024/01/09/business/boeing...

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (TugBoatEng)

What will people with "severe intellectual disabilities" contribute to the FAA?

Logistics for the entire UK Armed Forces used to be run out of a decaying abandoned fever hospital overlooking the city of Bath. One of its few redeeming features was the tea and bun trolley that meandered aimlessly around the site, operated by an unlikely looking pair - one physically capable of pushing the trolley around and the other intellectually capable of handling cash.

RE: Alaska Airlines flight forced to make an emergency landing...

I was told that the one pushing the trolley was a decorated Military Police undercover... The other dealing with the cash was NAAFI.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (I wouldn't call it an apology.... but its better than blaming the pilots which was what they have previously done for pretty much everything.)


There's one huge difference. With engineering decisions, I think I'm reasonably good. I have reasonable time to develop these. A pilot may not have that luxury; his decisions may be 'split second'.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

There are very few infrequent situations a snap decision is required. Fire and smoke, rejected takeoffs in the sim and the last 10ft landing in pretty bad weather in my experience and that only happened once last year.



RE: Alaska Airlines flight forced to make an emergency landing...

Thanks Alistair... didn't know that... thought the decision process was a lot faster; I suspect under some circumstances it may require prompt action.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Yes when your close to the ground or on fire.

But most of the time you have time for running a decision making algorithm.

Which is why the MACAS was so shocking for the majority. 5 seconds to spot it, analysis it, then action. Any longer and control forces were to much.

When the FAA test pilots went into the SIM pre warned it was going to happen the majority of them messed the first one up and couldn't recover.

There were only a couple of max Sims at the time world wide with the ability to simulate it.

And the is this landing not going to work decision isn't really a high level data processing. It's more of a picture isn't right let's get the hell out of here and do it again.

RE: Alaska Airlines flight forced to make an emergency landing...

5 seconds? That is as incorrect as possible. After 9 seconds the controls moved to put about 20 pounds on the controls and then would do nothing unless the pilot altered the trim.

It required at least 30 cumulative seconds of mistrim operation to become too much to handle and at no time did pilot electric trim become disabled.

The sim was - what if at 450 knots and full down trim could the pilots recover.

No one recalls that the first flight MCAS was seen as annoying before the pilots finally remembered the trim disable switch - 20 or so separate operations of MCAS, all fully retrimmed. Not only were they handling the issue, they even tried an experiment to turn the trim back on - MCAS responded to their trim input and they shut it back off.

The second flight - same result from the captain. No loss of control until his first officer thought the goal was to stop the trim wheels from moving instead of returning the plane to trim.

The third flight - they had plenty of time and made every wrong decision from the first stall warning. To know how bad this was - there were no sims in the world that could manage MCAS because no sim in the world had a way to falsify the AOA data but remain valid. Ethiopia had at least one MAX sim and would have known they could not train that scenario because the sim didn't support it; they didn't call Boeing to ask for a simulator software update, but put an inexperienced First Officer into the cockpit anyway.

RE: Alaska Airlines flight forced to make an emergency landing...

MCAS was pretty much beaten to death already. There is lots of blame to go around and Boeing certainly has their share.

Neither of the last 2 posts are correct about the details either.

RE: Alaska Airlines flight forced to make an emergency landing...

Show the errors based on the FDR data.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

5 seconds? That is as incorrect as possible. After 9 seconds the controls moved to put about 20 pounds on the controls
Respectfully, it may have been a good part of that 9 seconds or even a little more before the pilots started the 5 second "recognition" time.
That's strange the controls are getting heavy, to the controls are too heavy to manage.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

What is DEI?
I don't mean the textbook definition, but the real world application.
If the short list has only qualified candidates, then DEI may be acceptable and certainly can not be blamed for poor performance.
But, when some MBA thinks that DEI driven PR will improve the bottom line, and sets quotas, then middle managers have a choice:
Fudge the qualifications to make the quota,
or
Do an honest an professional job of screening candidates for the short list and watch the cheaters get the bonuses.
Not DEI but the implementation of DEI.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

As noted before - the controls become too heavy to manage after nearly 30 seconds of uncountered trim. The first crew and second captain managed to 100% undo the trim increment. The second F/O didn't offset any trim increment. The crew of ET-302 failed to counter the majority of the trim increment, but compounded the problem by failing to pull back the throttle as part of the required stall warning response.

RE: Alaska Airlines flight forced to make an emergency landing...

DEI needs a separate thread.

RE: Alaska Airlines flight forced to make an emergency landing...

Much like Sullys situation which was later proved in the sim about the ditch or try to return to the airport, Startle effect of anything usual happening has to be removed from the time line.

RE: Alaska Airlines flight forced to make an emergency landing...

oh btw in this one.

The previous events with the pressure controller throwing an error. Apparently the other two controllers didn't throw an error. If it had been uncontrollable cabin pressure because the door was off its seal then all 3 would have failed so I can understand why the techs went down a sensor failure route.

Apart from anything else a visual inspection outside shows up if a door isn't where it should be.

RE: Alaska Airlines flight forced to make an emergency landing...

The one common thing I've personally seen with "sensor failures" is that its never sensor failure.
The MTTF of pressure sensors is several hundred years. Not to say they don't happen, but it can make even one PI error potentially quite serious. If 3 are not actually monitoring pressure of the exact same point, ie different locations in the same containment envelop, there will be a restriction or opening in the envelop. Voting only works well if all are measuring pressure at the exact same place. The Boston gas explosion occured because the PI became disconnected.


RE: Alaska Airlines flight forced to make an emergency landing...

We get a fair few of them on older types.

Mainly because they don't change them due certification cost.

Bit like AoA sensor on the max.

RE: Alaska Airlines flight forced to make an emergency landing...

I should clarify, its pressure sensors I mean specifically.

Yes, they happen, but instrument error shouldn't be the first thing the tech guys think about and its like always #1. I don't know the MCs, but pressure sensors usually work. The computer reading them always bums out first. Big pet peve. Home appliances only run 2 yrs now without a microprocessor replacement. Before I could get 10 to 15yrs of trouble free (maybe not at max efficiency) ops out of them. Now it's $250 every 2 to 3 yrs. and its 2/3 to full cost of item to replace the micro.

DEI is just the new hip name for the old "affirmative action". Nothing's really changed there since 1978, except the people complaining about it. All the big problems still originate at the top and they keep blaming it on the bottom. I liked SBF's novel reason,"My girlfriend and my mom did it". 🤣 At least that was original.

RE: Alaska Airlines flight forced to make an emergency landing...

Three pressure controllers on the Max?

Thought they worked 1oo2 for most bits of control gear. Not airbus 2oo3.

Door sealing errors are also rather rare I would think. Those spare doors have been around for a long time since the 737-900 I think so many hours of service and they haven't fallen off before...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

Those spare doors have been around for a long time since the 737-900 I think so many hours of service and they haven't fallen off before...
It's only recently that they stopped putting the retaining bolts in place.

Sensors and pressure:
I surmise that it wasn't a failure as much as slightly slower pressure build-up due to an unseated door.
One sensor may have been slightly differently calibrated or differently placed.
Example:
A burner in an oil heater had a tendency to build up soot on the fire eye.
Eventually, the soot build-up would prevent a successful start.
Solution;
The fire eye had 7 seconds to see the flame else it aborted the start.
We programmed an alarm at 3 seconds.The alarm simply latched a pilot light that indicated;
"Slow Light-Off."
When the "Slow Light-Off" light came on the tech's could clean the fire eye at their convenience.
The Max was probably showing slow pressure build-up rather than failure to build pressure.
Not a faulty sensor, but slightly different calibration of the sensors.
That's easy do diagnose in hind sight.
Much harder to find in the shop.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

Respectfully, it may have been a good part of that 9 seconds or even a little more before the pilots started the 5 second "recognition" time.
That's strange the controls are getting heavy, to the controls are too heavy to manage.

Did you forget there are trim wheels that spin when the trim is changing? The pilot and copilot should be capable fairly easily figuring out that trim wheel movement + heavier stick = trim has moved in the wrong direction.

RE: Alaska Airlines flight forced to make an emergency landing...

I did not forget - I don't need to repeat the entire contents of all the reports; just the highlights. They could be blind and still feel the controls getting heavy.

RE: Alaska Airlines flight forced to make an emergency landing...

the 737 trim wheels are constant movement with the auto pilot in. Forwards and backwards. And they are rather fast and the trim window for manual handling is rather small. In fact uncertifiable small, for the regs just after the 737 NG was certified, never mind when the MAX was certified.

Startle is a known human performance issue.

There are several things happen.

Adrenaline discharge. Which triggers heart rate increase, your liver dumping glucose, and a few other things. One of them being the front lobes of your brain shutting down which are the part which deals with analytical thought and data processing.

Depending on the level of "flight or fight response" and other physiological factors depends how long it takes your front lobes to start working again at full capability.

So yes they might have felt them getting heavier but the analytical capacity just wasn't on line. So the fight or flight response was pull to lift the nose so that's what they did and it didn't work which prolonged the phycological effects.

to be honest it doesn't really matter it has been proved without a doubt it should never have been certified in the first place.

And the way things seem to be going trying to correct the certification issues with the 7 and the 10 they won't be certifiable until 2025, and then they will have to fix all the 8's and 9's. And that will be nearly over 6 years after it was grounded.


And there seems to be some movement in corporate ethics but there is a long way to go.

RE: Alaska Airlines flight forced to make an emergency landing...

pilot black humour

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (LittleInch)

Three pressure controllers on the Max?

I could be wrong (certainly not an expert on it), but I believe it's 2 automatic controllers (which automatically alternate on each flight), and a manual system consisting of a double throw momentary switch (3 position; close/-/open) and a position indicator for the outflow valve. It's essentially the same setup that has been on the 737 from the beginning, changing to a digital version with the NG.

See http://www.b737.org.uk/pressurisation.htm for lots of detail.

RE: Alaska Airlines flight forced to make an emergency landing...

That's how I understand it as well Murph.

They basically haven't changed the system since the 1960's or the outflow valve.

The double throw is just a motor controller to power the valve open and closed.

There is another valve which is an emergency depressurisation which is an on off button.

And I think 2 sprung pressure relief valves to deal with ultimate over pressure negative and positive which are just dumb springs with no control over.

its 2 controllers alternating controlling the singular valve, a manual method of controlling that valve, another separate valve which is binary open or closed, and the sprung valve or valves for hull integrity.

So it hits 3 level.



RE: Alaska Airlines flight forced to make an emergency landing...

So everything in the pressure monitoring and control system is working just fine. Pressure indicators and controllers. That's just great. The only thing remaing to do is start believing in the alarms.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Anybody else noticed a natural tendency for technicians to want to change the unit that has the warning light on it? Even if that's just the alarm panel. One of a long list of random lessons I would love to weave into basic technical education is "When complex systems go faulty, the cause may be miles away from the symptom" - and for engineers "design it so the technician has some chance of seeing what's going on inside the system"

RE: Alaska Airlines flight forced to make an emergency landing...

I have been watching South Main Auto for a long time now and - yup - whatever the idiot light says is broken is what they want to replace. Top of the heap so far was a dealer wanting to replace the power steering, the trailer controller, and what else I forget - about $5000 in components that all simultaneously reported problems. Actual problem? Bad ground strap between the body and the frame leading to a large voltage on the ground side of the components due to the resistance of the strap to high current.

There does seem to be a tendency in aviation to make everything a procedure. It seems to work for those who follow them - apparently no deaths from commercial aviation crashes anywhere in 2023. 2024 started rough though. It all goes south if there is something that has not been anticipated as the lack of adaptability leads to an inability to manage even small disturbances.

Not only do procedure writers need to anticipate potential problems, they have to also guess what pilots will think the problem is based on the symptoms and, if a pilot misses a symptom and guesses the wrong procedure, then it's all for naught.

RE: Alaska Airlines flight forced to make an emergency landing...

pretty much the way its gone in the 20 years I have been flying.

And actually the A220 has the least number of procedures of all the aircraft I have flown.

The ECAM system schedules the order you deal with things.

And it is obvious that Bombardier spent a lot of time and resources planning the human interaction with the machine and the presentation of data to the pilot.

And we have absolutely zero memory items. Jetstream we had 16 sets of them.

RE: Alaska Airlines flight forced to make an emergency landing...

When something not on ECAM comes up, expect pilots to freeze at the controls and blame the makers for the crash.

Does ECAM prompt to put the oxygen mask on when the plane explosively depressurizes? How long does it say the pilot can take? Does it detect when the pilot doesn't put the mask on and go to Plan B?

RE: Alaska Airlines flight forced to make an emergency landing...

like what?

We have a Emergency descent mode which arms above FL230 which if the pressurisation warning triggers with a cabin alt of 14500ft it squawks 7700 and then puts the alt select to FL150 and starts a emergency decent. We don't have to touch anything.

The ECAM check list tells us to done the masks and establish coms. Then gets into the guts of the rest of it.

Memory items for similar on other types had the none flying pilot putting the mask on then swapping controls and then the other did. Then establish coms.

History has shown with slow depressurisation the pilots get into troubleshooting trying not to declare a mayday. Then they pass out and when the fuel runs out that's when they descend.

So the A220 declares a mayday for you like it or not with the 7700 squawk.

RE: Alaska Airlines flight forced to make an emergency landing...

So the ECAM doesn't detect that the pilots just didn't put on masks? Would it auto-descend into a mountain face?

Would ECAM have told Sullenberger to go for the harbor? You already mentioned he didn't follow the procedure when he started the APU.

Would the ECAM have helped the DC-10 that lost an engine? Yes - like that. Even though it was found in simulators that the flight was recoverable if only the pilots had retracted the slats, pushed over and throttled up. What ECAM writer would consider that entire sequence?

RE: Alaska Airlines flight forced to make an emergency landing...

more humour.

RE: Alaska Airlines flight forced to make an emergency landing...

"So the ECAM doesn't detect that the pilots just didn't put on masks? Would it auto-descend into a mountain face?"

The not descending into a mountain face is on the cards with a link to the MSA for the alt select from the FMS. In Europe we only have 2 peaks above 4500m which would be an issue.

Those examples are airmanship decision making. ECAM's function is not for that. Its system diagnostics and appropriate actions, and tracking so miss configurations do not occur later.

It is a tool. and an extremely good one I have found so far in the sim.... No where near as many checklist screw ups that were common on other types.

The Q400's bus fail was just an nightmare if you didn't spot it within the 5 seconds before bus shedding started. And they always gave you it when you were busy with something else like a TCAS event which takes priority over a master caution or warning.

737 doesn't even have a central annunciator panel, its system status lights are like a Christmas tree all round the cockpit. That setup hasn't been certifiable since Late 70's early 80's on a new type certifications.





RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
Adding insult to injury...

Secretary Antony Blinken’s Boeing 737 out of Davos had a critical failure. He had to switch planes

https://www.cnn.com/2024/01/17/business/sec-of-sta...

An excerpt from the above item:

Secretary of State Antony Blinken was forced to change planes to return to Washington from Davos after his plane suffered what the traveling press was told was a critical failure related to an oxygen leak.

Blinken and the traveling party boarded the modified Boeing 737 jet in Zurich on Wednesday after a day and a half of meetings at the global summit in Davos.

The plane suffered the issue after boarding and the party was forced to deplane, according to traveling press.

A new, smaller aircraft was being sent for Blinken, and many in the traveling party will now be returning to Washington commercially, according to the traveling press.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

A new video is out on the 737 tech channel. No big surprises, just a quite detailed review of the various pieces of mounting and securing hardware around the plug door and their operation. He then goes on to cover the post-incident findings so far, and the pressurisation system including some discussion of the problems experienced prior to the incident.

737 Technical Aspects of AS1282 Updated

RE: Alaska Airlines flight forced to make an emergency landing...

Oh no - another breathless expression of stupidity from the press looking to gin up more airtime filling content.

An old plane in military service, likely maintained by the military or by military contract has a dispatch problem?

The same military cannot get the F-35s in order and they are newer and have all that electronic crap so beloved by the magenta line followers.

RE: Alaska Airlines flight forced to make an emergency landing...

Yeah, it sounds like just a routine problem discovered during the pre-flight checks. Probably related to the oxygen bottles for the flight deck masks. Sounds like an embarrassing incident for the USAF, not something that should be used to add to Boeing's current troubles.

The plane was likely a C-40B or C-40C. They are 737NGs with a 737-700 hull on 737-800 wings & gear, elements of the Boeing Business Jet programme, auxiliary fuel tanks for extended range, and various military upgrades.

RE: Alaska Airlines flight forced to make an emergency landing...

F35 is a designed to be an unstable aircraft.

if the electronic crap fails it is known that a human does not have the capabilities to fly it unassisted.

like it or not the progression away from analogue human monitored system has resulted in a colossal improvement in the accident stats.

the max is a magenta line aircraft. Just with 1960's crew alerting systems.



RE: Alaska Airlines flight forced to make an emergency landing...

Magenta line??

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Its developed over the years to indicate a reliance on automation.

The magenta line is on the NAV display indicating what has been programmed into the flight management system and is the currant active leg.

https://www.youtube.com/watch?v=5ESJH1NLMLs&t=...

RE: Alaska Airlines flight forced to make an emergency landing...

As an example approach into Geneva flown by me.



Magenta is my current leg. White is what it's going to do if I don't do anything.

Notice it has vertical profile as well. And indicates terrain. If the plan was to get near the ground it would trigger an alert and make that leg invalid. We would still need to change the selected alt to allow it to descend on the profile.

RE: Alaska Airlines flight forced to make an emergency landing...

I can give you more technicality's of the NAV performance and ATC separation requirements and why it really throws a spanner in the works if your not able to meet them. Which you can hand flying but its extremely high workload and liable for emails to start flying before you have even landed. If you want. But it really doesn't add to the thread topic and would be suited to somewhere else.

BTW at that time we were 10 meters horizontal NAV performance and 25 meters vertical. Once we get below 10 000ft the SBAS stuff kicks in and vertical comes down to 15meters. But everything remains on BARO vertically until the final approach fix doing a LVP approach on GNSS.

RE: Alaska Airlines flight forced to make an emergency landing...

another type of craft?

"Checks are to be carried out on a second Boeing aircraft model following the blowout of an unused door on one of its planes earlier this month.

The US Federal Aviation Administration grounded more than 170 of the 737 Max 9 fleet after a cabin panel broke away thousands of feet above the ground.

On Sunday, the agency said airlines should also inspect older 737-900ER models, which use the same door design.
The FAA described the move as an "added layer of safety".

It said there had been no reported issues with the 737-900ER, but that it uses the same style of panel to "plug" an unused door as the plane involved in the terrifying 5 January incident."

https://www.bbc.com/news/world-us-canada-68052160

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

It's the same.

They will have reused the same door certification.

Absolutely anything that's been used in the past that's certified all the way back to the original has been used so they can use grandfather cert rights.

Hence it only having 2 x AOA sensors and some nonsense that is good.

RE: Alaska Airlines flight forced to make an emergency landing...

Triple redundant AoA sensors on an Airbus sent it out of control when ice blocked two of them, voting the working one off the farm. The plane lost 4000 feet before the pilot realized the continuous nose-down trim was happening and pulled the circuit breakers on the related flight computers to get it back to a single sensor system. See 2014, Lufthansa flight 1829

The EASA response:

Quote:

As a result of this incident an Airworthiness Directive made mandatory the Aircraft Flight Manual amended by the procedure the manufacturer had described in the FOT and the OEB and a subsequent information of flight crews prior to the next flight. EASA issued a similar Airworthiness Directive for the aircraft types A330/340
just like Boeing did.

Turns out having a crew not nod off during the aerodynamics portion of the class saves lives when unreliable sensors are not detected by shoddy software rushed to market.

Such attention to quality: https://www.reddit.com/r/aviation/comments/bnm8ai/...

RE: Alaska Airlines flight forced to make an emergency landing...

That was a pitot blockage not AoA

They have two at the front and one on its tail AoA on old school AB

Pitot static Boeing and old school AB have the same 3 voting, AB has 4 to meet fbw cert think the 4th is the standby instruments but don't known

A220 has smart probes which does everything. Plus two old school AOA vanes. So we have 6

RE: Alaska Airlines flight forced to make an emergency landing...

"The Aviation Herald learned that the loss of altitude had been caused by two angle of attack sensors having frozen in their positions during climb at an angle, that caused the fly by wire protection to assume, the aircraft entered a stall while it climbed through FL310. The Alpha Protection activated forcing the aircraft to pitch down, which could not be corrected even by full back stick input. The crew eventually disconnected the related Air Data Units and was able to recover the aircraft."

Not that anyone would know more than a pilot.

RE: Alaska Airlines flight forced to make an emergency landing...

yes two out of three.

Boeing none Fly by wire you have two and have to go third regression after one goes which puts you in the same situation stick the nose down to known performance attitude.

And that's it all protections gone after one sensor failure. On the max original it would then drive you into the deck anyway unless you spotted it. You do that as per qrh and memory items and something else is still messing with your control inputs.

RE: Alaska Airlines flight forced to make an emergency landing...

BTW most of my current lot would follow the flight director on departure even if it commanded a 30 deg nose pitch up.



Us old farts stick the pitch attitude in the same place every time and ignore the speed... But apparently we are dinosaurs. Funnily enough the the unreliable airspeed checklist says to pitch to the same pitch attitude... Funny that....

RE: Alaska Airlines flight forced to make an emergency landing...

"On the max original it would then drive you into the deck anyway unless you spotted it."

At this point that is simply wrong. Not sure why continuing to be wrong about it, but there it is. There was the initial really bad speculation about how it worked and then the clear algorithm was made clear.

It only makes a single change unless retriggered by a pilot making a trim input with the trim switch. It won't drive anyone into the deck without pilot involvement. I know this. Why is this not obvious to anyone who looked at the FDR graphs from the accident reports? Maybe people aren't looking for facts when using false information as a bludgeon is so satisfying.

The problem with redundancy is if they depend on the same thing they are no longer redundant. They are duplicate. That is, they can all duplicate the failure exactly the same way at the same time.

RE: Alaska Airlines flight forced to make an emergency landing...

Are we not talking about independentcy, rather than redundancy?
If I substitute "unnecessary" in place of "redundancy". I can't makes sense of it.
The problem with unnecessary is if they depend on the same thing they are no longer unnecessary.
Eliminating the double negative...
The problem with unnecessary is if they depend on the same thing they are necessary.
The following makes sense to me, but i'm not sure if its still what you intend to say.
The problem with independency is if they depend on the same thing they are no longer independent.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

1) please take all of the endless and off topic and beaten to death discussions about flight controls and previous Max issues and what not into a separate thread.

2) some supposedly inside comments about the door plug issue: https://leehamnews.com/2024/01/15/unplanned-remova...

RE: Alaska Airlines flight forced to make an emergency landing...

Well, SWC, that writeup on leehamnews is quite the cold slap in the face for anyone working on aircraft, particularly the allegation about Spirit falsifying a repair record.

RE: Alaska Airlines flight forced to make an emergency landing...

This doesn't seem worth a new thread, and the mainstream media are already conflating it with this incident. It seems to have been picked up by pretty much everyone from the usual western press, to TMZ, to the Hindustan Times.

Virgin & Airbus must have been feeling left out of the media storm, and now have their own little "quality escape" with 4 missing fasteners on an A330. Not on the same scale as the Alaska MAX 9, at least for now, but maybe does have a bit of "something rotten in the State of Denmark" about it for the industry.

https://www.independent.co.uk/news/world/americas/...

RE: Alaska Airlines flight forced to make an emergency landing...

Juan Browne's latest on the 737 issues. The spotlight has turned to the 900ER for the same door plugs, although just recommended precautionary checks, rather than an airworthiness directive and mandatory grounding.

blancolirio - B-737 900ER DOOR UPDATE! 22 Jan 2024

RE: Alaska Airlines flight forced to make an emergency landing...

Every manufacturer has an opportunity to learn something here.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

SWC,

That's quite some apparently insider view and makes total sense. The door is not supposed to be simply opened then closed but "removed". If it's not "removed" then it skips a work package for someone to do a QA check to sign it off. Also it looks like Spirit employees are in the Boeing factory fixing things. It's perfectly reasonable that they will want to limit their work compared to what Boeing people do.

Also makes it possible that the replaced seal wasn't totally sealed hence the door might well have been in position and looking ok, but with a poor seal.

Some things I guess we'll never know.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Other than fatigue issues or something. I cannot see how the connection could fail if the bolt were installed with the castellated nut and the cotter pin. Even 'loose and wobbly' the parts would be contained. The connection was likely just missed. Are there other connections that were simply missed?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

...and the hits just keep on coming.
Link
I can't say I'd be comfortable buying more jets from them either, especially MAXes.

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

I also worked at McD then Boeing. Unlike most people I was not surprised when this incident happened.
When Boeing bought McD, most of us were laid off. Everything we built was outsourced. A lot of parts we manufactured should have been re-inspected when outsourced, but weren't to cut cost. Boeing is now just a final assy company.

Chris, CSWP
SolidWorks
ctophers home

RE: Alaska Airlines flight forced to make an emergency landing...

Nope, McD bought Boeing with Boeing's money; the St Louis mgmt tong took over. I was also there; left a couple of years later. I don't think their has been a single major Boeing program since the "merger" that has been delivered on time, commercial or military. And Boeing's "Partnership for Success" program for suppliers really meant "we are going to demand 20% cost reductions every year in an attempt to suck all of the profits out of you".

RE: Alaska Airlines flight forced to make an emergency landing...

If United split with Boeing, that's quite significant for their corporate history, as their name comes from William Boeing's United Aircraft and Transport Corporation, before the government forced the company to split up. Once upon a time, they were both part of the same corporate structure.

RE: Alaska Airlines flight forced to make an emergency landing...

2
Boeing put plenty of planes into the ground before McD. No aircraft maker has been on time or on budget, commercial or military, in the last 50 years or so.

Having been "merged" using the company as collateral by a smaller buyer, I understand the feeling of hatred as "cash flow" becomes a mantra. We had one "president" who fired the marketing department and then was surprised when contracts were drying up over his cost saving measure.

It becomes a toxin where middle managers who are realistic are selected out of the process and those who lie and blame subordinates for failure become prized as they are explaining the failure in the way top management can accept.

I was with McD for a year; most memorable was the number of people who noted that Old Man Mac frequently was on the factory floor, something Sanford never did. It's a shame the modern management doesn't include that as a requirement. Instead they manage investor expectations.

RE: Alaska Airlines flight forced to make an emergency landing...

Just now received the FAA SAFO about the door plug. I quote the recommended action here from the SAFO.

"Recommended Action: Operators are encouraged to conduct a visual inspection to ensure the door
plug is restrained from any movements through the two (2) upper guide track bolts and two (2) lower
arrestor bolts. Please refer to the Aircraft Maintenance Manual and 737-900ER Fuselage Plug Assembly
Maintenance Planning Document (MPD) for more information, regardless of if this inspection has been
conducted under the existing maintenance program prior to the EAD."

In the SAFO, the EAD is defined as the Emergency AD number 2024-02-51. The SAFO goes on to encourage operators to report findings to their Certificate Management Office (CMO).

RE: Alaska Airlines flight forced to make an emergency landing...

I saw Old Man Mac once. Didn't meet him, but watched him walk through.
I remember the big problems we had with the MD-11. I witnessed an engine drop once. It was too heavy for the overhead cranes. Was loud.

Chris, CSWP
SolidWorks
ctophers home

RE: Alaska Airlines flight forced to make an emergency landing...

My favorite McD memory was when the first space shuttle re-entered the atmosphere. They piped the NASA feed to the company wide speakers. It was such a thrill to hear the shuttle crew, coming out of the radio black-out period, announce they were over Hawaii and going Mach 40 while surrounded by a bunch of F-15 aerodynamic support engineers. It's a glider going nearly 20 times as fast as an air superiority fighter; sure, not particularly maneuverable, but at Mach 40 it doesn't have to be.

The expense of stopping the entire company for roughly 10 minutes for an event that was of interest to aviation enthusiasts was apparently worth it. Aviation wasn't just a business, it was a passion.

RE: Alaska Airlines flight forced to make an emergency landing...

I once went to work for a company that had recently had some new people buy in.
The new manager was extremely difficult to work for and impossible to work with.
I finally quit in frustration.
Time and again I would design a first rate and most economical electrical plan only to have it overridden by the manager with a second rate and more expensive plan.
His hubris was immense.
I felt bad about quitting and not sticking it out.
But I was just the first.
Within a year, everyone in the office who I had respect for had left.
This included the original owner and founder.
The word that I heard was that one day, the founder walked into the manager's office and said;
"I can't work with you, you SOB. I'm out of here. Have your lawyer contact my lawyer and buy me out."

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:


The expense of stopping the entire company for roughly 10 minutes for an event that was of interest to aviation enthusiasts was apparently worth it. Aviation wasn't just a business, it was a passion.

Many of us still think it's cool. Where I worked in 2018, everybody stopped for about 1/2 hour to watch the Spacex boosters launch up, and make the simultaneous pinpoint landings. Some stayed to watch the red car drift away, but for many like me, it was the first double-landing that we won't forget.

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
I met Sanford a couple of times, but that was when I was working for McAuto (McDonnell Douglas Automation) back in the 80's selling software, and we'd bring big customers to Saint Louis (I was working in California) to meet with the executives and to give them a tour of the 'bomber foundry', as we called it. Back in those days it was impressive when you could stand in one location in final assembly and see F-15's, F-18's and AV8B's, all at once. And if it happened to be a 'delivery day', we'd sometimes manage to watch some of the jets being flown out by military flight crews. And of course, since we had customers with us, we'd get to eat lunch in the executive dining room, with their well dressed waiters, and lets not forget, the cinnamon ice cream. Ah yes, those were the days...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
This doesn't sound good:

Alaska Airlines CEO: We found 'many' loose bolts on our Max 9 planes following near-disaster

"I'm angry," Ben Minicucci said. "This happened to Alaska Airlines. It happened to our guests and happened to our people."


https://www.nbcnews.com/business/rcna135316

An excerpt from the above item:

The CEO of Alaska Airlines said new, in-house inspections of the carrier's Boeing 737 Max 9 planes in the wake of a near-disaster earlier this month revealed that “many” of the aircraft were found to have loose bolts.

In an exclusive interview with NBC News senior correspondent Tom Costello, Alaska Airlines CEO Ben Minicucci discussed the findings of his company's inspections so far since the Jan. 5 incident, in which a panel on one of its Max 9 jets blew out midair on a flight carrying 177 people.

“I’m more than frustrated and disappointed,” he said. “I am angry. This happened to Alaska Airlines. It happened to our guests and happened to our people. And — my demand on Boeing is what are they going to do to improve their quality programs in-house.”

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

additional news...

"Two U.S. airlines have said they may abandon plans to buy more Boeing 737 MAX planes, a flashing red warning light for the aviation giant as it tries to quell its latest safety crisis.

The CEOs of United Airlines and Alaska Airlines both said Tuesday that they can’t necessarily count on the plane-maker for future orders, less than three weeks after a door panel blew off mid-air during an Alaska flight over Portland, Oregon.

Neither airline is canceling any orders yet, though United said it’s mulling removing another 737 model — the larger MAX 10 — from its fleet plans."

https://www.politico.com/news/2024/01/23/boeing-wo...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

My CEO is seen a fair bit by us lot. He has weekly CEO briefs. With open question sessions. I don't know how he does it to be honest, the questions he is asked.

He is also in the jumpseat when flying somewhere unless he is traveling with others. Puts the fear of god up the new First Officers.

He also fly's the aircraft occasionally. I have been in the sim with him. A particularly problematic airport for us crew got new ground handlers after one sector by him.

The story I like is they changed the paper cockpit coffee cups to some thin things with the structural integrity of a folded printer paper cup. Juggling act to make sure you didn't spill it before you burnt your fingers.

He got served a coffee in the new ones and just said what's this crap in my cockpits. Next day new cups turned up better than the old ones with thermal holding strip and you can basically use all day if your that way inclined which most of us are, just stick your initials on it and give it a rinse with the tea water tap.

He is also extremely hot making sure the technicians have what they need. Also its the only airline I have worked for that the majority of the technicians work at night when the aircraft are not flying. We only have line technicians during the day. The heavy maint run a day and night shift 4 days on 4 days off.

Some don't appreciate seeing him, and others don't like that he gets to know what's really happening at the coal face. He claims he doesn't deal with things that he hears about or see's, but things get changed relatively quickly if you make a comment on a subject that's valid. We had been bitching about the problematic airport for months, he did one turn round... he had requested to fly that flight after comments by one of the cabin crew.

RE: Alaska Airlines flight forced to make an emergency landing...

BTW the statements about dumping Boeing are just management chat for the media.

Airbus just doesn't have the production capacity to serve them in the next decade.

The 10% import tariff makes them expensive to boot.

RE: Alaska Airlines flight forced to make an emergency landing...

Delta have stepped up to claim their share of the media storm. The mainstream press are jumping all over the opportunity to bash Boeing a bit more, conflating it with the door plug, although this one seems likely beyond their control.

A Delta 757-200 lost a nose wheel while lining up for takeoff, with the wheel apparently rolling off the runway and down an embankment.

Delta Air Lines Boeing 757 Nose Wheel Detaches On Runway In Atlanta

RE: Alaska Airlines flight forced to make an emergency landing...

Good thing they have two. Being it was built 30yrs ago in 1992, it was not affected by current production issues, so there is no doubt the extra wheel was provided as an abundance of caution.

I had no idea that 30yr old aircraft were in anything other than cargo service. Back in the day, something 30yrs old would have been a red and white Southern Air Transport DC4 at a 2 hanger little field 50 miles out of town providing much needed shade for gophers.


--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

I think the government still has some for VIP transport

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

Two things remove wheels - maintainers not putting the fasteners correctly or the brakes dragging; it's not common to have nose-wheel brakes.

OTOH Airbus has perfected grinding the nosewheels off the planes along with large portions of the axles. They have made a large number of unsuccessful attempts to guarantee the wheels are aligned with the runway when the planes land.

RE: Alaska Airlines flight forced to make an emergency landing...

Brad...

"The more you know, the more you know you don't know."

might be more appropriate...

The more you know, the more you may not want to know.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Planes good to fly... what use is the NTSB investigation then?

RE: Alaska Airlines flight forced to make an emergency landing...

The NTSB investigation performs the most useful service of all.
Absolution from blame for the guilty and persecution of the innocent.

But more seriously, hopefully they will not completely ignore Alaska Air's potential contribution to increasing the risk by continuing to fly after the series of warning alarms and restricting distance from land rather than imposing altitude limits and if that was a correct or erroneous policy to keep it flying, or pull for detailed inspection and resolution. They might also try to determine exactly where, when and how the installation of the plug went wrong, what point missed their QA, if additional or better located pressure sensors would be of benefit and verify that the design or fit up procedures will be adequate in future. You know. Document the big picture. In the end, it's seldom only one thing that went wrong, so it's important to understand the path the events took on its way to becoming a serious incident, then put up the appropriate road blocks to stop it from happening again.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Its not up to the accident branches to dictate compliance policy.

Its the FAA's remit.

RE: Alaska Airlines flight forced to make an emergency landing...

Correct, they do investigations, but they may pass along certain "recommendations". What the agencies do with those is another thing.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Especially when it comes to that agency's not doing their jobs properly.

RE: Alaska Airlines flight forced to make an emergency landing...

Accident investigations in themselves can be taken as a recommendation of not to go down that same path again.

Yes, it's kind of a check and balance on system performance too. Macondo blew up the old Mineral Management Service. Completely dismantled and rebuilt from the ocean floor up, now under entirely new management of the Bureau of Ocean Energy Management, The Bureau of Safety and Environmental Enforcement (BSEE) now has responsibility for oversight of offshore oil and gas operations. The Coast Guard also has a part. MMS... gone.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

The Boeing Issue Isn’t About Bolts
Engineering TV (Engineering.com is a globally trusted source for professional engineering content with a mission to inspire the engineering professional to be and do better.)

https://youtu.be/UKR79e7BKcY

RE: Alaska Airlines flight forced to make an emergency landing...

It's not over. Its just beginning.

Customers getting wiseguy?
What if I don’t want to fly on a Max 9?
Alaska Air will let passengers change planes penalty free.
https://www.nytimes.com/2024/01/25/travel/boeing-7...

And today its Anti-icers
https://youtu.be/yZr-5_fdFdA?si=2YZI15FwYaioSyyf



--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Latest from Juan Browne. He's covering the FAA response and the steps they require to get the MAX 9s back into service (within days). They are also not going to allow Boeing to increase their production rate until the quality systems are fixed.

blancolirio - Cleared For Takeoff! Boeing 737 Max-9 UPDATE 26 Jan 2024

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (And today its Anti-icers)


The de-icer issue clearly shows the FAA is 'broken'. They are acting in the interests of companies and not the passengers.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

This thread is toooooo long

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

Interesting op-ed that mirrors many of the changes in Boeing management that many who have worked at Boeing have posted about.

https://hbswk.hbs.edu/item/why-boeings-problems-wi...

I find though the common complaint about bean-counters taking over and kicking the engineers to the curb somewhat simplistic as the Boeing and McDonnell Douglas top leadership teams were all engineers, albeit often armed with MBAs.

RE: Alaska Airlines flight forced to make an emergency landing...

In other words, you don't think a top floor, corner office, a Gulfstream, stock options, a $60,000,000 golden parachute and the shareholder mafia could change the engineer's perspective of corporate governance.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

I am certain the financial lures can change perspectives. I think it is significant and overlooked that the 'bean-counters' have not been straight accountant actuarial non-technical outsiders brought in to run the business by efficiency studies and ROI optimization. The 'bean-counters' have been biased toward technical insiders who are / should be / could be aware of the effects of relentlessly chasing profit over quality, safety, and staff morale.

RE: Alaska Airlines flight forced to make an emergency landing...

Just because a person has an engineering degree doesn't mean they necessarily have a passion for a machine over money. I have worked with people who had engineering degrees but used that only as a stepping stone to management - in essence to move away from the nuts and bolts of engineering.

RE: Alaska Airlines flight forced to make an emergency landing...

Seems they had the door out at Boeing production so Spirt locals could fix a snag with it.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Brian)

in essence to move away from the nuts and bolts of engineering

Pity the technicians followed their lead....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

doesn't mean they necessarily have a passion for a machine over money

Its often more than that. A few years ago I jumped from engineering to govt regulation for more money and a guaranteed 37.5 hour workweek. I miss the challenge of engineering but have a much broader, still very interesting view of industry now and am working with a higher level of industry/corporate management. More importantly, there's no stress to constantly have new innovations completed yesterday and more time for non-work activities. I always managed to balance burning the candle at both ends without sacrificing my family, health, or hobbies, but being in the auto industry definitely soured me a bit on automotive hobbies and made scheduling my vacations/personal life difficult.

RE: Alaska Airlines flight forced to make an emergency landing...

CWB1 - good points - as you point out generalizations can miss the details of each person's situation and motivation.

Quote (CWB1)

More importantly, there's no stress to constantly have new innovations completed yesterday

This aspect of engineering never changes! 😀

RE: Alaska Airlines flight forced to make an emergency landing...

3
I think all this talk about financial lures, bean counters, and engineers with MBAs misses the point. A good example is to consider the failures that led NASA to lose 2 space shuttles and 14 astronauts. Poor management decisions that led to both accidents were certainly NOT driven by bottom line financial considerations. Egotism, hubris and bombastic personalities generally serve themselves, whether for financial or any other reason. I'm not saying finances don't matter, but I wouldn't be inclined to put blame there first.

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

You have a star, you completely correct

RE: Alaska Airlines flight forced to make an emergency landing...

Negative personality traits and profit motives may have nothing at all to do with it.

Normalization of adverse events is enough.

If something didn't fail yesterday or the day before or the day before that, then it is easy to believe it will not fail today.

The problem is not knowing just how close to failure something is if it doesn't fail, particularly if the mode of failure or contributors to failure aren't imagined.

Sure, engineers know that a door departing mid-flight is a really bad outcome, but the assemblers don't. For them it becomes just another day where things aren't assembled correctly. Every day upper management is believing that the line workers are doing what the instructions say, and they very likely are, but they aren't asking what the line does when the instructions are created on the fly.

Like the o-rings on the shuttle boosters. NASA management likely knew that the o-rings were getting chewed up on most every flight. But they held and nothing bad happened.

The line workers get chewed up every day. And they held. Until they didn't.

RE: Alaska Airlines flight forced to make an emergency landing...

I doubt the missing bolts or incorrect installation traces directly back to the CEO; this could be entirely an assembly procedure screw up. It is not the same type of problem experienced before, in that no design choice was purposely chosen to save money, even though the design was unstable in climb and subsequently "fixed" with software. That's on the CEO's desk. This one not so much. It is apparently the result of an erroneous, or incomplete procedure. Of course, the buck stops at the top, but the physical trace back to CEO level is a bit tortuous.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

Bad management has momentum. The start of Boeing's troubles date back a couple of decades and no matter what they say and how they approach it, they won't be turning it around soon.

Brad Waybright

The more you know, the more you know you don't know.

RE: Alaska Airlines flight forced to make an emergency landing...

As an aside what state will the rest of the hull be in after an explosive decompression?

I presume a 3 month old aircraft isn't written off. But it must be a hefty about of man hours to get it flying again.

I presume Boeing will foot the bill though...

RE: Alaska Airlines flight forced to make an emergency landing...

Good point, Alistair... I had no idea that the sudden decompression could affect the rest of the plane... but, it would be a 'sudden jolt'.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I have zero clue either.

It wasn't that high so cabin differential also not that big but I would have thought explosive decompression is more of an ultimate load case not operating.

I presume the mounting frame will have to come out and various things replaced round that.

Rear pressure bulkhead damage/fatigue life reduced?

RE: Alaska Airlines flight forced to make an emergency landing...

Was it hubris that led to cuts on labour and the retaliation against inspectors who did their job honestly?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

I think that was about the finding that one of the "new" plants which was meant to be producing precision parts they went and inspected and found the workers were producing them with none certified hand tools instead of laser profile cutters.

They then refused the parts in the assembly shop.

And the solution was sack the inspectors that were refusing the parts.

RE: Alaska Airlines flight forced to make an emergency landing...

That finding is a complete surprise. To no one. I have the preliminary report being downloaded and I hope it answers the better question. What kept the door in place for so many flights. It should have remained in place for zero flights and should not have been in place leaving the workstation it was (re)installed at.

RE: Alaska Airlines flight forced to make an emergency landing...

You can read it on the CNN web page I linked to.

RE: Alaska Airlines flight forced to make an emergency landing...

The size of the bolts still looks very small and it is easy to see why they were not missed. Looks like they were there before they removed the door though.

No mention here of the way in which the two document systems were reported as working against each other but guess that comes later.

No real mention of why they thought the door went on this flight and not on the previous 100+ flights.

Looks like the cockpit door is intended to fly open on a depressurisation...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

I hate it when I rebuild an engine and have a handful of bolts left over...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

I hate it when I rebuild an engine and have a handful of bolts left over...

But, it wasn't even as complicated as an engine; there were only 8(?) bolts to start with, and they left off at least 3. What's truly annoying is that the hatch was only removed to get access to the damaged rivets, which were in the bulkhead adjacent to the hatch.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Alaska Airlines flight forced to make an emergency landing...

The Boeing guy before ems to say it was removed a second time to fix an issue with the seal.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

The door flying open is another undocumented safety feature which apparently Boeing decided the pilots didn't need to know about.

Normally they have blowout vent panels but 1960's design... Bullet proof door retrofitted.

But now the door is none compliant because everyone knows if you want to get into the cockpit you just take a window out and it will bang open.

Quite how that one will play out is anyone's guess. It will likely be all the NG series of aircraft which have the same feature.

If they deem it none compliant for Flight deck security and needing fixed that's billions.

Modern designs the outflow valve isn't in the tail, the air has multiple routes to escape the cockpit, ours it gets directed through the footwell into the forward cargo hold which is heated. And there is ducting from the toilets taking it to the same place. There are blow out panels on the door and in the hold as well.

RE: Alaska Airlines flight forced to make an emergency landing...

Does the passenger floor have panels that work in both directions to stop the floor breaking?

Taking a window out to get onto the flight deck is a bit OTT...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

My guess is that the cockpit door only failed due to the HUGE hole in the airframe in this case compared to a slower depressurisation caused by a much smalller area window failure?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

No it didn't fail it was meant to let loose and open as a safety feature. More than likely due structural load on that section.

I would post the fcom from the a220 but suspect it would breach some rule.

Yes there are blow out panels for both airflow directions and a few other things before they ultimately release.

Survivable Explosive decompression is pretty rare.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (But now the door is none compliant because everyone knows if you want to get into the cockpit you just take a window out and it will bang open.)


That opens another can of worms, maybe. Because of the large surface area of a door, like the panel, it would be subject to quite a force.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

It certainly does and I think someone has decided to drop them in it for it.

Now it's public....

I suspect it was a none public certification waver.

I am sure the USA pilots unions will have something to say about it.

Some of those retro fitted cockpit doors caused some major headaches structurally. But those in the forum will know more about it than me.

It wouldn't suprise me though if it's exactly the same as the retro fit compliance setup...

RE: Alaska Airlines flight forced to make an emergency landing...

I think this is a real problem of extending certification of new models, based on earlier models where significant changes have been made.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Dik et al, there is no problem with the way certification authoritiesdeal with change. The process is addressed in part 21.101 - called the 'changed product rule', and provides pragmatic criteria for the identification of the appropriate cert basis for modifications to existing designs, i.e. work to the latest amendment for 'major' design changes.
If you look at the 737 tcds you will see the cert basis becomes incrrasingly complex with each generation, as various new amendments become applicable to the incrementally changed systems/structures.
Furthermore the regulator & applicant can agree upon special conditions where the basic regulations are deemed inadequate for specific novel design features, which is the case for just about every contemporary aircraft type.
It's a misconception that 737ng/max are designed entirely to 1960s design standards.

RE: Alaska Airlines flight forced to make an emergency landing...

I thought this was funny.

Chris, CSWP
SolidWorks
ctophers home

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
Thanks for reposting the above image winky smile

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

3
Better than the previous Alaska Airlines disaster, eh? Also a repeat of the FAA failed oversight which in turn is the US Congress failing to apportion sufficient funds to the agency to do the job correctly.

RE: Alaska Airlines flight forced to make an emergency landing...

Oops, sorry John. Completely missed that.
banghead

Chris, CSWP
SolidWorks
ctophers home

RE: Alaska Airlines flight forced to make an emergency landing...

Wouldn't worry its made me laugh twice

Much like the off road memes about the off road in Vilnius last week. Black humour

RE: Alaska Airlines flight forced to make an emergency landing...

Latest from the 737 tech channel, summary and analysis of the NTSB preliminary report:

AS1282 NTSB Preliminary Report

RE: Alaska Airlines flight forced to make an emergency landing...

I have been trying to keep up with the sequence of events. I would appreciate correction if I missed something.

As I understand it, the four missing bolts are there only to keep the door plug from moving upwards. It is the 12 pads surrounding the door plug that transfer load from the door plug into the corresponding frame pads and thus into the airframe. So the aircraft flew some flights with the pads still making enough contact and this would continue as long as the door plug did not move upwards too far.

Here is my opinion of the sequence of events:

Aircraft leaves Boeing with 4 bolts missing.
Aircraft flies several flights, door plug is slowly moving upwards from vibration and pressure differential.
On the incident flight door plug eventually moves far enough upwards for the 12 pads to disengage.
Door plug departs.

RE: Alaska Airlines flight forced to make an emergency landing...

debodine - yep, you got it. what many of us suspected from the start.

RE: Alaska Airlines flight forced to make an emergency landing...

The four ""missing" "bolts"" are essentially retaining pins. They are not loaded axially. The "bolts" themselves are kept in place with castle nuts and cotter pins, if they were ever there in the first place.

RE: Alaska Airlines flight forced to make an emergency landing...

It may have hit a 'bump' to dislodge the door initially from the restraints.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Landing?

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
Turbulence...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

Also don't forget there is are two springs at the bottom which "assist" removal of the door plug. It's not clear to me what sort of downwards force is required to get the door plug to seat or if the force essentially makes the door "weightless" or feel a lot lighter than its 25 kg actual weight.

The pads and lugs also have fine adjustment screws so that the plug is always in contact with the frame at those 12 locations and hence a bit of friction when on the ground and even more when pressurised. So maybe there was a little bit of time when the aircraft was slightly negative pressure to the outside and the door was pushed in a bit and then started lifting.

Going to be the most expensive bolts in history....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

The adjustment screws are set to have clearance on the ground. Differential air pressure forces the door out to produce contact between the screws and mating pads.

RE: Alaska Airlines flight forced to make an emergency landing...

How much clearance? Can't be much.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Thanks all, I appreciate the feedback.

RE: Alaska Airlines flight forced to make an emergency landing...

My son sent me this from the internet (somewhere)

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I once tried to visit that church, or a similar one. There are a few still left standing. Took most of the day to get there. When we finally rounded the last curve in the road ... nothing. Empty meadow. It had burned completely to the ground during just the previous month. No fire alarm or extinguishing system.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

RE: Alaska Airlines flight forced to make an emergency landing...

I have run out of free articles on Seattle times.

Seems to be a lot of headlines coming out about FAA and Boeing about quality reset.

Is it anything substantive or just headlines?

RE: Alaska Airlines flight forced to make an emergency landing...

paste the page links into this site to read: https://12ft.io/

RE: Alaska Airlines flight forced to make an emergency landing...

The clock's ticking, again...

https://www.design-engineering.com/faa-gives-boein...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

yeah, the FAA has finally stumbled over a spine in one of their closets.

RE: Alaska Airlines flight forced to make an emergency landing...

SWComposites your post is quite humorous and unfortunately sobering

RE: Alaska Airlines flight forced to make an emergency landing...

"Regulatory agency currently completing audit of Seattle factory where planes, like the 737 Max, are assembled."

Nope. Missed the mark.
The FAA needs to audit the factories in Wichita, not Seattle.
Everyone knows those are owned by Spirit, and that Spirit is at least 1/2 of the problem.
80% of the touch-time labour done on 737's is done by Spirit.

RE: Alaska Airlines flight forced to make an emergency landing...

all facilities?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Seems Boeing is in talks to buy Sprint

RE: Alaska Airlines flight forced to make an emergency landing...

For those who are not aware, the Spirit plant used to be called Boeing, Wichita before Spirit bought it.

RE: Alaska Airlines flight forced to make an emergency landing...

its way bigger than that these days.

Although I can't seem to find any issue with the quality in the other production lines.

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
And Boeing Wichita is where they used to manufacture Minuteman Missiles.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

Also Steerman aircraft before that.

That plant has some amazing history.



RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
Yes, Wichita, Kansas was the center for the manufacture of civil aircraft and they've repurposed the old airport terminal into an air museum, most of which is dedicated to the history of civil aviation and the various manufactures of small aircraft. They also had an outstanding display of engines, again, most of them from civil aircraft from over the years.

Here's a shot of the old terminal:


August 2017 (Sony a6000, 16-50mm)

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

its on my bucket list to visit if I ever go back to the USA

RE: Alaska Airlines flight forced to make an emergency landing...

This is pretty bad:

https://www.faa.gov/newsroom/review-panels-final-r...

To give some context, the FAA set up this review board in March last year (before the doors blew off, so to speak) to examine Boeing's organization with respect to how delegated "Unit Members" are being respected. Unit Members are supposed to represent the FAA and provide oversight from within the company. It seems Boeing's culture roused their ire the whole time. They don't come right out and call it "sandbagging" but you get the idea.

The emphasis of this report is more focused on management of their engineering personnel than a review of their production system, which would speak more about "quality control". Instead this review looked at "safety management systems" or SMS which is the aviation term for building a workplace culture that upholds safety at all levels.

RE: Alaska Airlines flight forced to make an emergency landing...

Is the unfavorable interaction based on FAA/review board member statements or is this word on the street? Not doubting the conclusion, just looking for substantiation.

Simply, I can accept the push-back and resistance is true as I have been subject to similar "We are here to fix your problem" investigators before when the investigators had a solution in mind before arriving, usually a solution they had developed as a way to solve all problems everywhere. With the variety of members on this review board I would expect there were multiple different mutually exclusive such solutions.

One would think if a safety management system was the way to go the FAA would have created one for all of US aviation to use. US General Aviation kills around as many people every year as both MAX crashes did, and have been killing people at that rate for decades. Perhaps the FAA would consider fixing deaths in the US?? Dunno.

I am sure if the Boeing response is just as vague as the request for an SMS (like, give everyone an additional thing to hang with their badge that says "SMS - Use It" or maybe woven into new lanyards, that's the ticket)is no one on the committee or in Congress will be more or less favorably impressed than if Boeing rolls out a 50,000 page document in 5 point single spaced text with quarter inch margins on legal sized paper that covers 25,000 possible circumstances. Whatever Boeing publishes or does, I bet there are memos already written, maybe attached to scheduled e-mails, expressing displeasure with the approach in extremely vague terms, but certainly bombastic.

RE: Alaska Airlines flight forced to make an emergency landing...

Spar how long do you think SMS takes to implement time wise?.

My personal experience with airlines which is the basic level is it takes years to actually function as intended.

There are people that never really buy into it and have to find other jobs otherwise it kills the process of the whole buying into it.

It also seems to me that getting consultants in to dictate processes is only the first box ticking stage. It actually working as intended takes years and a hard core of "locals" that are on it every single working day.

My work I did the induction courses and thought this is too good too be true... it didn't quite work as it sounded with the Q400. There was still do a power reset and don't put it in the techlog by some technicians.

COVID layoffs and transition to single A220 fleet have made a colossal difference. No small part is due to the philosophy of the health management of the aircraft and the inability to reset faults by technicians or crew without documentation trails that the reset has been done.

The known argumentative technicians never came back after covid.



RE: Alaska Airlines flight forced to make an emergency landing...

This was a natural consequence of withdrawing FAA oversight in the first place... when you live in a glass house...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

FAA's funding runs out in March this year.

I can understand why FAA and the OEM's want the cost base moved away from Political variable funding arguments.

Projects put on hold because of some political drama unfolding.

What happens when all the inspectors and certifiers stop getting paid?

RE: Alaska Airlines flight forced to make an emergency landing...

re Spar’s post,
Yep, the report is pretty bad.
Any tool, whether it is SMS or something else, is just that, its a tool. If its not backed up by real management commitment, then its useless. Or worse.
Since the merger its clearly apparent that the management focus has been on stock price and share buybacks. Go read the history since 1997.
The excessive outsourcing and decimation of parts of the Boeing engineering workforce prior to the 787 program led to significant problems, delays and huge cost over runs. That in turn delayed any spending on a 737NG replacement. And when the A320neo started to sell very well, Boeing panicked and launched the “just stuff some new engines on and don’t change anything else” Max.
And then in order to sell the less capable and flawed Max they had to greatly reduce the price. Which led to extreme pressures on the suppliers and factory to pump out airplanes fast and cheap.
The Covid induced layoffs and retirements greatly reduced the manufacturing experience level.
So here we are.
Boeing can either somehow completely turn the management focus, or risk crashing and burning. Not sure buying Spirit (the Boeing bits; Airbus isn’t going to allow Boeing to be a supplier to them) is really going to help.

RE: Alaska Airlines flight forced to make an emergency landing...

Alistair - implementing an real working SMS into a big OEM is even more difficult and will take a lot longer than in an airline.

RE: Alaska Airlines flight forced to make an emergency landing...

And back to the report, the only thing that will really fix the identified issues is to yank the ODA and go back to FAA appointed and managed DERs. I’ve posted before about how Boeing lobbying Congress got the ODA system created.

RE: Alaska Airlines flight forced to make an emergency landing...

2
And congress did it because they didn't (and still won't) fund the FAA to do the assigned job.
There are two parties at the root of this, The Boeing BOD and Congress.
Everyone else is dealing with the fallout from them.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Alaska Airlines flight forced to make an emergency landing...

The "don't change anything" part of MAX was because that's what the customers demanded. Boeing could keep the price the same as the 320neo and still be cost effective as a result of the airlines not having to change any operations at all.

If you mean by "flawed" that foreign airlines had been reducing pilot hand-flying training, coupled with a flawed public relations response to the false narrative put out by the responsible-for-the-second-crash airline operator, then yes. How was Boeing to understand that the airlines were lying to them about pilot qualifications?

Build "flawless" planes and you get PIA 8303.

If Boeing re-integrates with Spirit they also get the benefit of running only one management burden instead of paying for two; that includes having only one quality management system, which seems to be the core of the latest problem.

I have yet to see any sign that the ODA was the source of any problem to the extent that FAA involvement would have made one bit of difference. The FAA already had the tools to understand and analyze MCAS, which they originally failed to do, as did every other airline and CAA on the planet after the Lion Air crash, because that crash was correctly identified as a pilot based crash. Or maybe all the rest did and not the second crash operation.

Notice who did not get dragged before Congress - the company that miscalibrated the Lion Air AoA sensor nor was the FAA for not ensuring that company had processes in place to prevent that miscalibration and detect that miscalibration.

RE: Alaska Airlines flight forced to make an emergency landing...

SWComposites that's why I referred to it as basic.

It takes long enough with just an end user setup. Which is why I asked the question.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Alistair_Heaton)

Spar how long do you think SMS takes to implement time wise?.

Hi Alistair,
My experience is a lot like yours - SMS takes a long time. For those old-timers who've been there done that, the shift in thinking is hard. For the young it can seem like the normal way to do business. Then and there the friction starts. It is really hard to implement, too. Management doesn't just have to buy in, they have to be involved in the deployment of the system, which literally takes years. For executives who answer to quarterly reports, that's hard. So top-to-bottom everyone in the organization tends to struggle. Including the engineers.

The engineering struggle with SMS in my particular experience is the change from decision making to decision accountability. When people in certification have been examining regulatory compliance for decades, and somebody comes along with a SMS plan, it's easy to respond "yeah I already do that, go away". When you've been authorized to make a finding of compliance for long enough that you know the requirement by heart, it's hard to allow people into your decision process asking questions about how and what you chose. And then they expect you to report on your activity in minute detail. "Get outta my hair." It took a while for me, and I needed a boss who had bought into this to steer me straight. I am now reaping benefits from a system that should be used to build trust.

One way I've found it useful is that I've been able to self-report on slip-ups in our department's work using SMS. Reporting the mistake itself can come across as embarrassing at best or an urgent safety concern at worst. In the non-critical cases, having a SMS system already in place and self-reporting helps. In my experience (of only 2 cases) I found that reporting by SMS and letting the SMS system steer the resolution, that put an end to the issue with our regulator. They trusted our people to find and implement the solution, and we reported progress all the way until it was closed. No further action, no follow up, no red-flag to be picked on for the next audit. That's what it looks like when your organization has earned the trust of the regulators.

So while I don't believe SMS is perfect, and my company's deployment of SMS is also not perfect, we keep getting better at it, and there are benefits when it is used right. So I was disappointed to read the report, but it is consistent with what I have been told by some current and former Boeing employees I've met.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (SWComposites)

the only thing that will really fix the identified issues is to yank the ODA and go back to FAA appointed and managed DERs. I’ve posted before about how Boeing lobbying Congress got the ODA system created.

Do you think they would?

Your view of the USA's aerospace industry may be different from mine. From here it seems like there's Boeing and then there's everyone else. Only one of them is "too big to fail" thus the FAA isn't likely to make such moves. In the past decade or two the political support for the FAA to make bold moves has literally vanished. Just look at how they were thrown on the back foot by the FCC over 5G frequency deployment, today dealing with a rash of near-misses, and the number of times their budget was cut, suspended, or simply wasn't renewed. They didn't come out of the MAX scandal looking clean and white either.

RE: Alaska Airlines flight forced to make an emergency landing...

I self report all the time and it seems to throw people out because they presume pilots are trying to cover up and make excuses.

Just being honest and saying I messed up I need to do xyz to ensure it doesn't happen again takes all the wind out of their sails.

This machine I learned very early on it was pointless trying to hide anything. Every problem is recorded and gets sent to 3-4 places 2 of which are external to the company.

If people do 2-3 plus power resets about the same issue it triggers a huge flag somewhere. The only protection we have as crew is to make sure its recorded in the tech log.

You can see me change over the last 18 months in the captains seat. Last 6 months I have 2 flight data monitoring flags which were firm landings below level 1 out of phase inspection and a full folder of voyage report completions. And zero explain yourself from the boss or flight safety emails.

It takes a while though to get used to how to make the system tick.

I might add as Captain when I say "I" I refer to the crew as a whole as I am responsible for their actions.

So my two FDM the reports only triggered conformation that the process was completed correctly ie. identify a landing could be classed as firm, record it, inform maint control, data download performed, relevant requirements performed and aircraft released.

The triggering of the process post flight due to HMU trigger not flight crew apparently is a whole different level of phone calls and emails. The way I do it, two weeks after you submit the report you just get an email saying report complete saying procedures have been complied with.

As a note with this machine a straight G reading seems to bare no relation to what your bum feels. Pointing straight down the runway no wind and you ask for download because it feels ruff and they come back you were less than 1.6 your released.

Any lateral velocity and the G ramps up. So your bum might say nothing wrong with that and it triggers a level 1 inspection.

So I think the G disclosed is actually a load index which is a combination of a multiple number of variables some of which have way more loading effect than straight up down deceleration of a sexual assault of an innocent runway with a 50 ton plus aircraft.

RE: Alaska Airlines flight forced to make an emergency landing...

On being wrong | Kathryn Schulz
https://www.youtube.com/watch?v=QleRgTBMX88

SMS is great when you realize a mistake has been made. It may help avoid making that mistake again.

I don't see how it prevents a mistake being made in the first place. As the above video discusses, being wrong feels just like being right.

A response to a problem seems to me like it should include a detailed analysis of a typical problem it is intended to repair or avoid and show how it would have been effective in doing so. Like, what information was available to the participants that the response would have caused them to act differently? Not a fan of cure-alls that with clear hindsight into a problem isn't shown to clearly deal with that problem.

RE: Alaska Airlines flight forced to make an emergency landing...

On the subject of SMS

As mentioned by 3DDave PIA 8303 accident report is an utterly disgusting chain of events,

https://avherald.com/files/(PUBLIC%20VERSION)%20FI...

The accident was actually just the very end of a long chain of faults spread over years and a serious management fault which has been there for the whole time i have worked as a pilot. PIA was on my no fly list before I trained to be a pilot 23 years ago now.

The next comment I won't expand on too much as it would be inappropriate to the individuals and company's.

In my social circle of pilots there have been several cases of none colleague pilots being removed from the responsibility of command due to the SMS system pulling data from multiple sources including training records. This has led to a trigger of a review of their suitability to command a multicrew public transport aircraft. This has happened in multiple different company's. From low cost carriers through to legacy full service airlines and not just in EASA.

So as an industry there does seem to be movement to remove the protection of "mates" sim checks and personal input to protect people who are not meeting the grade or are struggling.

And a personal conversation with someone that was downgraded due to this process was actually quite surprising to me. They don't work with me. It was a lay over crew using the same hotel.

They spoke of their feelings of relief about being removed from the role and just going back to flying the machine as a first officer.

I am seriously considering not running to the bitter end of my career as a Captain, down grade myself, get a CPL issued and not have to deal with all the crap. Just keep the flights safe and waggle the stick.

RE: Alaska Airlines flight forced to make an emergency landing...

3DDave from what I am seeing is that its also being used to identify hidden trends before the fault occurs to be identified.

A220 heath management unit is point in case.

Lets face it pilots are pretty rubbish at feeding back quality data about the machine.

The HMU and FDR records colossal amounts of data far more than a human could even monitor never mind interpret.

Trends of method of operation and average skill base they seem to be able to work with and implement. And change relatively quickly without waiting for a smoking wreck in the ground to trigger the in depth investigation.

My last sim featured a lot of exercises in relation to dealing with high energy events. I am told that the data from which was recorded and sent to Canada. All A220 operators did similar exercises at the request of Airbus.

I have zero clue what will happen with such data, but it will be real operational data of what they can expect the airframe to be exposed to by real pilots. Or even if it was fleet wide or just my company.

Not some made up nonsense of presumption of "A properly trained pilot should be able to cope with this situation" in relation to presumption of a procedure filling a hole in the Swiss cheese model.

When in reality highly experienced test pilots when the situation is dumped on them had to go into make it up as they were going along mode. With less than 90% being able to save the day. Normal line pilots it would have been below 50%.

RE: Alaska Airlines flight forced to make an emergency landing...

So, was PIA 8303 a problem with the design of the plane?

The situation the pilots were started at had the plane over max velocity and maximum trim and likely after the trim system was renabled and MCAS retriggered.

Regular test pilots would recognize the need to follow the stall warning procedure straight away and properly retrimmed and not allowed it to go out of control, just like the first crew did and the captain of the second crew did.

Is trimming pitch forces just an option for pilots to learn? Can they skip that class and still pass the course?

RE: Alaska Airlines flight forced to make an emergency landing...

From what I can tell the FAA didn't actually know or realise what MCAS actually did or the effects of a failure in the big system picture to the normal operations.

The certifiers had white washed its effects or failure modes.

The trim window was special from a certification POV. If the NG had been certified less than a month later than it was then it couldn't have been certified.

The real killer for the trained pilot should have been able to cope was actually put to rest by a series of sim sessions in at the time in one of only two world wide simulators that was a MAX simulator. Everyone else only had access to NG simulators which were deemed sufficient due to the certification paper work put in to the FAA about training etc.

The FAA ran I think it was 12 737 experienced 737 NG pilots through it with a MCAS event.

The pilots were 6 from FAA system and 2 from EASA and the rest from other pilot geographical groups.

It was very quickly put under zero information disclosure rules.

By all accounts it really wasn't pretty with no real link between training backgrounds. That's where these percentages of less than 50% of normal line pilots started being quoted.

The real killer was when the FAA director at the time who was a very experienced 737 driver from classics through to NG and as a check airman was getting so much conflicting opinion he went and did it himself.

Literally with in minutes of him coming out of the sim the tone and process of the FAA completely changed into the hardcore that is seen today on the subject. And has continued since he left the role.

Again it was completely locked down from a public disclosure POV.

Most of us are pretty sure he crashed and burned in a quite spectacular fashion.

There are still people that have the POV that it was purely a pilot incompetency issue but I haven't seen anyone in the power circles even mention it since the grounding. In fact by far the bulk of the "chat" has been the NG should have never have been certified. And half the MAX problems are linked to its certification and the major changes rule.

RE: Alaska Airlines flight forced to make an emergency landing...

The PIA is the complete management and running of everything from the regulator down failure.

There may well be design changes that could have legitimately stopped the chain of events.

The PIA is a true big picture failure of the whole system. Not just the people involved on the day who don't get me wrong were at fault completely.

But as far as I understand the SMS is meant to track and rectify issues in the big picture not just deal with individual events.

RE: Alaska Airlines flight forced to make an emergency landing...

Spar - no I don’t think the FAA will yank the ODA. Probably should, but it won’t happen without a completely worse incident.

There is a reason PIA is banned from flying to many countries. Complete system failure.

RE: Alaska Airlines flight forced to make an emergency landing...

I wonder;
Why should Congress and the tax payers pay for FAA inspections.
If I do an electrical inspection, The permit fee more than covers the cost of inspections.
If inspections are a necessary part of aircraft assembly, why is Boeing and the final customer not paying the cost?
The present inspection system is a de-facto government subsidy of the aircraft industry.
Congress can solve a large part of the problem by cutting the subsidies and allowing the FAA to charge Boeing for the cost of inspections.
This will reduce improve safety and reduce costs to the taxpayer.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Since the results of the simulations was 100% covered up I assume that it was only to cover the last 30 seconds of the flight. Prove me wrong.

Every pilot going into the test would have heard and known about the trim problem, so the only test would be for the last 30 second.

One reason to cover it up was the CAA that declared the last crash pilots made no mistakes; to find that it was avoidable would be to blame the pilots of the last crash and we all know there is a tremendous pressure on pilots to never do that. The other reason was to dodge the responsibility the FAA had - they had the means to understand MCAS but chose not to. MCAS was already known - Boeing told the FAA. The director needed to save the FAA.

Edit - On top of which, the FAA had just approved the Emergency AD, which the Ethiopians had claimed they followed exactly. This left the FAA directly responsible for issuing a document that clearly, if the Ethiopians were believed, caused ET-302 to crash. The FAA head had to shift all that blame somewhere and the public and Congress already disliked Boeing because of the false statements, so it was easy to just pile on.

Th NG has had an exemplary safety record. Odd that anyone would argue for not certifying a successful plane.

Everyone knew all about MCAS after the Lion Air crash. Don't care at all what happened before that. Doesn't matter. Until the Lion Air crash it was a latent problem. The first crash did not lead to the big stink. The false story about the ET-302 crash did.

I don't understand about the simulators - no simulators had the ability to produce a false AoA sensor reading to feed the MCAS software. Ethiopia owned at least one MAX simulator and had to reconfigure it after the crash to do their investigation. They clearly did not do simulator testing after Lion Air and before their crash because they could not have done so and, had they tried, they would have reported that to Boeing. No one had considered that to be a failure mode so it was not part of the simulator software or would ever have been part of the training.

RE: Alaska Airlines flight forced to make an emergency landing...

waross - there are two levels of inspection in play. There is the design inspection - validating every aspect of the design, and the fabrication inspection.

One problem I can see is this. Suppose the FAA comes in and they say we need to have 10,000 engineers, full time, to review all your design work and they are going to bill at $1000 per hour each, full time. Maybe the FAA also says all certification testing will be done by FAA test pilots. Being a regulatory agency what happens? Well, clearly no company can afford that level of oversight. Either Boeing closes the doors or they get Congress to intervene. Congress makes limits and then the FAA bitches and moans they cannot attract enough qualified people and cannot do all the work - and here we are.

For fabrication inspection you have an experimental plane the FAA might inspect it for free, but if you aren't near an FAA inspector you can hire a designated airworthiness representative (DAR) and they will charge whatever they will charge. It may include mileage to and from your location and can be a few hundred to a couple of thousand dollars.

RE: Alaska Airlines flight forced to make an emergency landing...

Hi Bill,
My comment about "there's Boeing and there's everyone else" is meant to apply to your question. The rules are fair, but the powers aren't fair.

Through all of these failures (the MCAS, the door, the quality errors) I keep finding that the rules in place would serve, if only they were applied fairly, or applied at all.

RE: Alaska Airlines flight forced to make an emergency landing...

It would be an extremely strange SIM setup if it was the last 30 seconds. You can't reset slew into the air.

It wouldn't save any time.

The whole ground airborne logic would be completely confused.

The accident CAA's wasn't involved with this point.

It was pure Boeing and the FAA with the FAA deciding on the emergency grounding and if the piss was being taken by Boeing. And it was yes and yes

RE: Alaska Airlines flight forced to make an emergency landing...

2
Was looking for the details on Sims.

Turns out at the time there was only one SIM that could do the mcas which was the Boeing SIM for certification.

Found this article which some might find interesting. There is stuff I didn't know in it.

Just to note a level D SIM is a bit of a strange beast. I am not going to attempt to pretend that I have a clue about them.

From what can tell it's an aircraft with simulated data inject to replace the sensor inputs.

https://www.afacwa.org/the_inside_story_of_mcas_se...

RE: Alaska Airlines flight forced to make an emergency landing...

That article was from well before the real reason for the ET-302 crash was published.

Quote:

Pilots who pull back forcefully on the column — sometimes called the stick — might suddenly feel a slackening of resistance.
That's incorrect. What they would feel is that the stick load wasn't increasing as fast at the G load, not that there was ever a slackening - the stick force continued to rise.

Quote:

The failure analysis didn’t appear to consider the possibility that MCAS could trigger repeatedly, as it did on both accident flights. Moving multiple times in 0.6 or 2.5 increments depending on the speed, it effectively had unlimited authority if pilots did not intervene
In fact - the only reason for multiple triggering is because the pilots intervened. MCAS evaluated the trim when the trim changed. If the pilots stopped pressing the trim button MCAS stopped reacting. When the pilots press the trim switch, they had priority to set the trim, giving them time to disable the trim motors.

Quote:

The pilots’ struggles to control their planes before both MAX crashes suggest that the FAA’s three-second guidance for expected pilot response time, upon which part of Boeing’s system safety analysis was based, needs to be carefully reassessed.

All three flights had pilots responding before the 3 second mark and had far more than 3 seconds to make suitable corrections. It's simply the case that the FO on Lion Air and both pilots on ET-302 never made a correct decision. An hour would not have been long enough for them.

Interesting, but too many holes in the article to be reliable when compared to the actual FDR data.

.....

A pilot in the simulator can fly the defective profile to the same condition as the last 30 seconds and then see what can be done. A test pilot would certainly be aware of the trim condition, particularly since that was well known before these tests were made. The pilots they lined up

Not sure what you mean - the accident CAA reported they had MAX simulators in their final report. It doesn't matter that the FAA was doing tests independently. What matters is if the simulator had an input for AoA other than the SMYD system. The article doesn't answer that.

The FAA had a motive to prove that they had no blame for issuing the Emergency AD, that the flight were completely unrecoverable, even though the first MCAS incident proved they were easily managed, once the pilots recalled the existence of the trim motor disable switches after getting the plane in trim.

What I indicated - that Ethiopian never trained their pilots because they could not train them on the sensor failure because the software they had could not manage the failed, but still valid, AoA input. Knowing this, they went ahead and flew a plane with a known defect and a newly out-of-school First Officer.

A level D sim is a cockpit full mock-up on a motion platform; it's not an aircraft. It has no sensors so of course the inputs are simulated.

RE: Alaska Airlines flight forced to make an emergency landing...

Level D is not what you state.

The driver of the responses is the actual aircraft hardware it is not a software generated response.

It's single core single thread 286's and 486 processors

RE: Alaska Airlines flight forced to make an emergency landing...

The certification owner pulled the certification.

The debate stops there. What ever the accident regulator says.

There is over 27 violations stopping further max variants being certified.

The list of AD for the NG must be having some accountants putting dates in calenders for bankruptcy.

The electric system on the NG is an utter mess currently. Your talking 2000 plus hours next D chech

RE: Alaska Airlines flight forced to make an emergency landing...

AH, you're sounding more and more like a Boeing hater, rather than an interested observer.

RE: Alaska Airlines flight forced to make an emergency landing...

"Level D is not what you state."

It is according to makers of Level D simulators. Perhaps the word "mockup" is what triggered you. A fully operational mockup or replica? Would that be calming? They don't necessarily have all flight-qualified controls, they just appear and act the same.

The hardware from the plane runs software, so everything they do is a software generated response. You are making an unimportant distinction.

I said, quite clearly, that the inputs are simulated because there are no sensors. Look at the Level D simulators and you won't see externally mounted AoA sensors or pitot-static systems nor is it located inside a pressure capable wind tunnel.

https://www.cae.com/civil-aviation/aviation-simula...

"CAE 7000XR Series Level D Full-flight Simulator"

RE: Alaska Airlines flight forced to make an emergency landing...

We have procedural simulators which are purely computer hardware and everything is generated by the computer model input, reaction and output.

The level D's are sensor data injected to the real aircraft hardware giving the same response as one that fly's. Be it digital or analogue sensor. As I stated.

And the room that you never see pictures of which is usually bigger than the box on legs has all manner of stuff in it. It doesn't have a wind tunnel but older sims did used to have AoA vanes actuated by servo motors to move them.

The level D's I have been in have OEM serialised parts from the aircraft, in fact they take from functioning aircraft to fix them sometimes.

It is neither a mock-up or replica.

The CAE7000 is what I spend 8 hours in every 6 months.

RE: Alaska Airlines flight forced to make an emergency landing...

It's a mock up of the plane, a replica of the flight deck. It is not an actual plane or a real flight deck. It is a simulator even if some parts are flight hardware.

Mince words all you like. I don't care what simulator you use. It's not a MAX simulator and has no bearing on this topic.

There has been no suggestion anyone considered or made provision for putting into the 737 MAX simulator system a different AoA than via the AoA sensor system, so no one could have simulated the Lion Air crash sequence.

You seem to have a blind spot that the aircraft external situation was not represented by any sensor input because you say "The level D's are sensor data injected to the real aircraft hardware" That's the point. The conditions of the three incidents had a difference between what the aircraft actually experienced and what the sensors claimed was happening. The simulators weren't designed to simulate that input and no one saw that as a requirement that they do.

Since that was the case they could also not have verified the Emergency AD instructions worked. Since that could not be done, it was irresponsible of Ethiopian, in possession of a MAX simulator, to put a new grad into a 737 MAX when Boeing itself announced that the software would be updated. They could have parked the plane and waited or they could have flown with manual trim control and no autopilot. Instead they got two pilots who cannot handle a stall warning procedure to literally save their lives. How did they get through training?

On top of that the FAA issued that Emergency AD without verification, so when the FAA did their secret testing it was motivated to show that the instructions didn't work; but I bet every pilot had no problem and they buried that result. Or maybe it would show the FAA pilot certification sucks and pilots are given licenses who should not have them. The great thing about secrets is everyone can speculate and since the truth is the first crew, completely unawares, flew 90 minutes to a safe landing, it's clearly only a basic skills issue.

Either result would relieve Boeing of responsibility and put the FAA on the spot for not requiring 50 repetitions of trim runaway training over 4 weeks before being allowed back into the front seats.

RE: Alaska Airlines flight forced to make an emergency landing...

It is a real flight deck same components, we even have to take into account which firmware the components are.

There are 2 real Fadecs in the room downstairs.

But I agree that the fundamental issue was that the sensor failure was never considered. As the article https://www.afacwa.org/the_inside_story_of_mcas_se... states.

But I actually agree the crew skill profile was not taken into account as well in certification. The 3 seconds reaction time is completely out the window now. Which is one of the many issues with the MAX 7 and 10.

The skill profile has changed in the 20 years I have been flying. I am unusual in my peer group. it is completely different to the skill set which could be presumed when the 737 was first certified.

I spent 5000 hours driving a none autopilot analogue turboprop. I have muscle reactions that the straight to jet pilots just don't have. Also the number of system failures dealt with on the Jetstream 31/32 was colossal in comparison to the J41, Q400 and A220.

I also spent 900 hours teaching stalling and the basic "skills" in piper tomahawks PA38's.

There are a few of us with similar backgrounds that mess up the sim profiles due to our reactions. Call it a third sense of impending doom which triggers a power plus attitude equals performance solution. It is considered by some that we ditch the automation to soon. And its just annoying that we are able to fly out of it without the automation. But the ability to do that is 10's of thousands of flights.

Even at the time instructing I could see the difference between pilots trained on a Cessna and those trained on a Tommy. The Tommy was considered brutal and dangerous by a lot of instructors and pilots. I thought it was brilliant for teaching the basics apart from the stupid trim system.

Training these days is done on FADEC controlled engines and glass cockpits. And the aircraft are significantly more reliable.

And the fatality rate is a fraction of what it was 30 years ago.

Reading about something on paper is not the same as experiencing it. And real life is significantly different to simulated even on these level D's you just can't generate the physiological changes which occur in a, you can't screw this up situation.

I would expect the reactions of a 737 Classic or 757 pilot would be different to a 737 NG only pilot.

And no its not Boeing hating. I have an issue as well with Airbus and their refusal to rerun the Software, hardware, liveware interaction of their system (SHELL model). How many crashes need to occur because of the thrust levers not moving giving tactile feedback of power setting.

Airbus also have an issue with the Angle of attack sensor system. They do have 3. But there is something seriously going on with it currently. And it may very well be linked to the skill level of the pilots.

Currently I suspect the group of pilots with the most reactive skill set for dealing with issues is more than likely the Russians. They are dealing with system down grades and events daily due to no spare parts and running at less than the minimum equipment list.

RE: Alaska Airlines flight forced to make an emergency landing...

And now the NTSB is pissed at Boeing for withholding and deleting info on the door removal/installation. Cripe.

RE: Alaska Airlines flight forced to make an emergency landing...

Meh - I doubt that Boeing has or had any information about handling the door. Boeing did not touch it nor did they ask anyone else to do so. At best they have a sign-off that the door was correctly installed when it arrived with the rest of the fuselage. The only Boeing information that appears to be deleted are factory security tapes that are on a 30 day loop. They aren't a construction record so they aren't expected to be retained.

What is more interesting is that Spirit did not direct-hire the workers who did the rivets. They appear to have come from one or more of several contract employee suppliers. Spirit should have information about the door. They are responsible for installation of the door as well as it's subsequent removal and re-install and NTSB has gotten no documents from them nor the names of the workers who did the rivet work.

Spirit has had enough time to raise ducks from eggs and get them in a row, so I don't know what they gain by delay. I think it is clear that no matter what or when, this is going to hurt. They need to get it over with now.

My guess. Delays while some executives negotiate their separation packages.

RE: Alaska Airlines flight forced to make an emergency landing...

The door was opened in the Boeing Renton plant so that Spirit (or someone) could repair some adjacent fasteners. Boeing is refusing to release who was involved in those operations that happened in their factory. It looks bad.

RE: Alaska Airlines flight forced to make an emergency landing...

Yeah, while I do think Spirit have at least 50% responsibility for the failure to re-secure the plug after the remedial work, it does seem that there was a failure in Boeing's quality/safety systems which should have been used to properly track all safety critical processes in their factory.

RE: Alaska Airlines flight forced to make an emergency landing...

Seems they had yet another rudder hard over on the max....

This rudder hard over must have been running nearly 20 years.

RE: Alaska Airlines flight forced to make an emergency landing...

Seems like they didn't. They had a case where the pedals didn't move for a short time on the ground.

https://finance.yahoo.com/news/investigators-confi...

Not great, but not a "hard over" condition and entirely unrelated to the previous slide-valve problem.

RE: Alaska Airlines flight forced to make an emergency landing...

Thank goodness for that, it sounds an utter nightmare to deal with.

RE: Alaska Airlines flight forced to make an emergency landing...

Thank goodness Airbus hasn't killed anyone with the multiple design iteration to get the nose wheel to actually point forward when lowered for landing.

RE: Alaska Airlines flight forced to make an emergency landing...

Comes under not my problem

Although I do personally agree with it needs sorted.

Max hard over of a primary flight control is a bit of a different league to burning a tyre out... Especially as the arelions are not power full enough to counter the secondary effects of yaw at full rudder.

But maybe I am being picky

RE: Alaska Airlines flight forced to make an emergency landing...

No 737 issues are your problem either.

RE: Alaska Airlines flight forced to make an emergency landing...

Utter nonsense

The whole of the aviation certification process and down grading is my business. I have to strap my backside into these machines and have to interact with them all on a daily basis.

I have zero desire for a 1 OEM market for hardware.

The NG was an utter abortion of certification never mind the MAX.

RE: Alaska Airlines flight forced to make an emergency landing...

Then the Airbus problem is also your problem. Pick a lane, you are weaving.

RE: Alaska Airlines flight forced to make an emergency landing...

its honestly not.

Its not even classed as a major.

I am looking about runway removal and diversion. Which it doesn't feature in.

It happens that rarely with zero fatalities its a none event for certification.

Pain in the arse yes.... we carry fuel to deal with these events but as they happen that rarely its a none factor.

RE: Alaska Airlines flight forced to make an emergency landing...

It's a pattern of failure through multiple design variations. Why the lack of concern? It hasn't killed anyone, yet.

RE: Alaska Airlines flight forced to make an emergency landing...

True but I haven't heard of any recently.

I had something similar on the Jetstream41 You don't loose directional control its pretty much a none event apart from the paper work afterwards.

And all AB ones resulted with a modification going through I think I read. No half baked fiddles with operating procedures relying on human intervention to stop it happening again.



Current threats on the A220 is ice ridges on the radar dome causing shitty air to mess with the smart probes.

And inadvertent selection of autopilot on departure. Which is linked to the position of the auto thrust button and Autopilot button. And the auto thrust kicking out due to pilots being ruff putting the levers up or a x wind. They put a firmware through last year which has stopped the xwind issue.

RE: Alaska Airlines flight forced to make an emergency landing...

There is a saying accidents happen in three's but this is getting silly...

BTW this is pilot stupidity.

They wanted to roll to the end

The end is greasy with jet blast from holding aircraft and waiting for TO.

You try and take a corner at 30 knts you slide....

RE: Alaska Airlines flight forced to make an emergency landing...

The tower directed the plane to exit at the far end and to keep it snappy, apparently to give the following aircraft more rapid access. Pilot was dumb for following tower request and Tower was dumb for packing them in so tight.

RE: Alaska Airlines flight forced to make an emergency landing...

100% agree.

I thought the pilots requested roll to the end.

Anything past the touch down markers is greasy.

RE: Alaska Airlines flight forced to make an emergency landing...

Actually thinking about it.

With it being a geared fan what's the reverse performance difference between a max and the NG like?

I have only ever experienced geared fan reverse. And it's not very awe inspiring compared to a turboprop in beta in full reverse. Which will give you it even when you start reversing back down the runway.

The Pw1500G comes off the thrust at 35knts forward speed.

I can imagine if your used to more performance and it staying producing down to 0 knots ground speed. It would be an understandable human error to get your deceleration distance wrong.

This will be an issue with the A320neo as well in mixed fleets.

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
It looks like this has just been ratcheted-up one more notch:

DOJ Opens Criminal Investigation Into The Alaska Airlines 737 Plane Blowout, Report Says

The Wall Street Journal reports the Justice Department has launched a criminal investigation into the Boeing jetliner blowout.


https://www.huffpost.com/entry/oregon-emergency-la...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

It seems the common denominator is Boeing. pipe

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

United has two emergencies at my local airport this week. They lost a wheel from a 777 and had a hydraulic failure on a 320.

I hear Spirits builds airframes for Boeing and Airbus...

RE: Alaska Airlines flight forced to make an emergency landing...

The wheel dropping off is in a different league. But also linked to airline


The rest of it is just run of the mill. Linked to the airline. Not the aircraft type.

It's just every event is currently headline news.

Hydraulics have 2 main back up methods and another 2-3 emergency.

The brakes are powered by them and spoilers so it makes a performance difference. So you have to declare them.

Lost count the number of times I dumped the hydraulic system over Wales on the Jetstream.

RE: Alaska Airlines flight forced to make an emergency landing...

Memo to Boeing, cc Alaskan


--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

The rumour is total electrical failure for 45 seconds then when it came back there was a large elevator movement.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Alaska Airlines flight forced to make an emergency landing...

Coincidence?

https://www.bbc.com/news/business-68534703

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (https://www.bbc.com/news/business-68534703)

In the days before his death, he had been giving evidence in a whistleblower lawsuit against the company.

He had been due to undergo further questioning on Saturday. When he did not appear, enquiries were made at his hotel.

He was subsequently found dead in his truck in the hotel car park.

RE: Alaska Airlines flight forced to make an emergency landing...

Just some back ground.

Old aircraft they used simple failure criteria for control disconnect. A servo pulls to many amps and it would trip and dump everything on the pilot. And it could be 20lb rotation out of trip if it was a Jetstream. For the 5 Jetstream 31/32 in Europe with an autopilot. The US j31/32 they allowed a none bae certified yaw damper.

The yaw damper was a analogue double integral control unit off the left hand direction gyro. And if someone messed with the compass flux valve selection you could get 10 plus degrees instantaneous heading changes which triggered a collosal rudder kick.

Electrics you were on your own sorting out the bus configurations to get things back.

But the engines wouldn't miss a beat and the primary instruments apart from the horizon no change apart from the oscillator on the altimeter and vsi.

RE: Alaska Airlines flight forced to make an emergency landing...

Q400 systems had more complex interactions with automatic fault isolation. Electric faults it would be 30 seconds up to 3 mins of chaos. The auto pilot would sometimes kick out sometimes stay in.

The big gotcha was not spotting a yellow caution bus failure. At the end of the three minutes you would be left with a complete panels worth of red and yellows with no clue what the base issue was. If you went red priorities following the qrh you would end up shutting an engine down. If you spotted the bus failure or just chanced your luck using experience in the SIM and went for the bus card one switch and you would get everything back.

RE: Alaska Airlines flight forced to make an emergency landing...

We need a Q400 thread. Maybe another for Jetstream.

RE: Alaska Airlines flight forced to make an emergency landing...

A220 flybywire

Fully automatic electrical isolation. Flight control redundance etc etc.

Haven't seen any issues in real life in 2500 hours with either system.

Type rating covers all systems then there is a 3 years cycle through them winter summer conditions.

The scenario triggered and those of us with an older type experience. Tripped the automatics out and sat and watched it doing it's thing. Flight director went a bit funny for a while so just used the real horizon and back up artificial horizon. Eventually it finished.

They gave us then a bit of a unreliable instrument issue we landed and that was it. Pretty much a none event for a sim.

Examiner afterwards said you ruined that exercise for the FO. None of the system issues occured because none of them were online. It was meant to eventually result in taking the automatics out.

And you lot have the muscle skills to fly for hours
Manually without thinking about it. They don't.

I suspect this case they left the automatics in to the hard recovery to the profile. Or it was fms driven.

Modern planes the ride quality and fuel efficiency goes to hell with a pilot manually flying them. So we are encouraged not to. Plus it increases workload.



RE: Alaska Airlines flight forced to make an emergency landing...

I use them as examples because I have full documentation on them plus experience.

They are also pretty good examples of the philosophy change over the decades.

And why using 1960's human response is doomed to failure in this day and age to stop fatalities.


RE: Alaska Airlines flight forced to make an emergency landing...

None lost a door due to a factory floor error.

RE: Alaska Airlines flight forced to make an emergency landing...

Thankfully no doors lost.

Pretty unique CV's for that experience base.

RE: Alaska Airlines flight forced to make an emergency landing...

This thread is "Alaska Airlines flight forced to make an emergency landing... " dealing with the loss of a door.

RE: Alaska Airlines flight forced to make an emergency landing...

But it's all based round the same ethics and accountability problems.

They have stated now there is no paperwork on the removal of the door or the reworking of the rivets it was removed to work on.

RE: Alaska Airlines flight forced to make an emergency landing...

https://fortune.com/2024/03/12/criminal-focus-boei...

I agree completely that the legal process does nothing to aid better safety.

The root cause needs understood and prevent it occurring again.

Root cause to me is financial types overiding Engineering forcing them to use extremely dubious compromises to and in appropriate assumptions to drive the Engineering.

I am pretty sure it's the same with the production.

Kpi linked to quality and excellence instead of accountants bonuses.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote:

I agree completely that the legal process does nothing to aid better safety.

The root cause needs understood and prevent it occurring again.
I disagree Alistair.
It has been shown conclusively that the present system is not working at Boeing.

Quote:

Root cause to me is financial types overiding Engineering forcing them to use extremely dubious compromises to and in appropriate assumptions to drive the Engineering.
I think that it is time for the "Financial Types" to face criminal scrutiny for their actions in overiding engineering.

Those opposing the investigation have changed "Too Big to Fail" to "Too Big to Investigate".
I think that it is appropriate that after a serious incident there will be a criminal investigation.
If the investigation shows criminal misconduct, there should be charges.
The present Boeing and Spirit culture allow the "Financial Types" to make dangerous engineering decisions that put the public in harm's way with no responsibility for their actions.
How many deaths and accidents will it take before the 'Financial Types" are held criminally responsible for their decisions?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Going after the Technical workers just prevents the true story being found out of what the financial types have been doing.

It's like that silly sod of a test pilot and the no documentation of mcas or informing the FAA certification of changes to it when it got hot rodded into a killer system.

With the premise of a 1960's stick and rudder boy would be around to save the day in 2020.

Btw the reason why I keep making this point is I have my doubt's I could have caught it. I definitely don't have any experience of working an aircraft without a central announcator panel playing hunt the red light in a Xmas tree when the master caution goes off.

All the SEP training aircraft had them. And it's been a certification requirement for over half a century to have one on new types or better.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (The root cause needs understood and prevent it occurring again.)


I suspect the root cause if profit!

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

You would not have caught 50 pounds of trim load after being told there is the potential for a trim load problem?

The first crew managed 100%, the second captain managed 100%; the most informed crew managed to f' every step. Hmmm. Every control available in each case functioned. The wheel trim button worked and stopped and could reverse the trim at any time, even to the point when the pilots, against training, attempted to re-engage the Autopilot with the stall warning and stick shaking.

No one had to look at anything except the instruments. Airspeed, trim setting, throttle setting. Are none of those on the list of things a pilot in command needs to worry about anymore and instead to have the Magic 8 Ball tell him what to do? Where is the dashboard warning about feathering the props on final?

RE: Alaska Airlines flight forced to make an emergency landing...

Yes, which is why I see it as pointless chasing the technical for relatively minor finger pointing. It isn't going to fix the root cause

RE: Alaska Airlines flight forced to make an emergency landing...

Having watched a 737 trim wheel moving during a perfectly normal departure on the jump seat that thing really motors.

And it's constant even while hand flying.

It's seriously loud and rapid with collosal trim changes. And some of them make zero sense forward, backwards, some hunting then back into the huge trim changes.

There are issues with trim window for control forces which was never present with the none stretched versions.

As I say I am not 100% sure I would have caught it. 2/3 of crew didn't.

If there needs to be a specific skill set to fly them so be it.. But nobody would buy them.

RE: Alaska Airlines flight forced to make an emergency landing...

No one said anything about the trim wheel. There is a trim indicator and a trim force.

The captain of the second crew did catch it. 100%. For some reason the co-pilot thought trim force of over 50 pounds was normal and did not use the general purpose Cockpit Resource Management skill of talking with the captain about the increasing trim force. Which is why the FAA reminded pilots to use the trim button.

Does one need a specific skill not to set the pitch of the props to zero on final? Maybe no one should buy Dash-8 or Q400s.

Does one need a specific skill not to come in fast and high as PIA 8303? Maybe no one should buy an Airbus.

RE: Alaska Airlines flight forced to make an emergency landing...

Most don't set them to zero torque on touch down.

The gradient of the trim force and requirement to reduce it within a none realistic time span which isn't present on a working aircraft or previous training aircraft is.

RE: Alaska Airlines flight forced to make an emergency landing...

Anyway - all of that is for the other thread. This thread is about a failure in factory floor process management, not cockpit resource management.

RE: Alaska Airlines flight forced to make an emergency landing...

It's all linked..

It's an ethical failure of process from design through to production.

If the initial design process is flawed and concepts are alien to modern pilots. The production process is going to be just as alien.

RE: Alaska Airlines flight forced to make an emergency landing...

I suspect that we have a misunderstanding Alistair.
In Canada, the law makes upper management responsible for implementing and enforcing safety standards.
In the event of an industrial injury, the general manager may be found guilty of failing to ensure that proper safety procedures were in place and were followed.
Just the threat of actual jail time for top management turned the safety culture around quickly on Canadian construction projects.
This was the type of investigation that I visualized for Boeing and Spirit.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: Alaska Airlines flight forced to make an emergency landing...

Well we went through this in Aberdeen after Piper Alpha.

The US system is set up so that the upper management is pretty much protected from legal consequences over there management policy's and actions. And the workers get penalised for carrying them out.

When they worked out the US oil managers were in line to have to justify themselves in court they were gone never to be seen again. They said that the pipeline boss that didn't stop pumping should be the one to carry the can. Not the big boss in Aberdeen who had fired the last one that shutdown the field.

That boss was charged but had left the country.

From what I have seen so far with the MAX not much has changed. They go after the small fry that can't
afford to pay legal fees not the big bosses. It's the workers fault for obeying instructions not the bosses fault for giving them.

Hopefully I am incorrect in the way it works.

RE: Alaska Airlines flight forced to make an emergency landing...

What is liquid dawn soap?

RE: Alaska Airlines flight forced to make an emergency landing...

It's a brand of dish soap. I've used it to help fit crane tires, pump shaft seals, and as a cable lube. I would be surprised if Boeings SOP specifies dish soap.

RE: Alaska Airlines flight forced to make an emergency landing...

Yes - unlike the UK that put subpostmasters into prison because a foreign based company lied. The US is quite different that way.

RE: Alaska Airlines flight forced to make an emergency landing...

I didn't know the use if dish detergent was common...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Yes - unlike the UK that put subpostmasters into prison because a foreign based company lied.)


I can imagine the American class action suit on that one... bankrupt the country.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

I have only seen the technical use seal lubricant which is 50 dollars for 500ml.

Wouldn't have thought normal soap plays nice with the materials used.

RE: Alaska Airlines flight forced to make an emergency landing...

It's working it's way through parliament at the moment. Think it's 4500 people getting clean records and compensation.

The boss of the post office at the has been stripped of various things I think.

Post office is government run still I think. It has a load of special law surrounding it.

Don't know that much about it.

RE: Alaska Airlines flight forced to make an emergency landing...

"Wouldn't have thought normal soap plays nice with the materials used."

Why not? People use it on their bare hands.

RE: Alaska Airlines flight forced to make an emergency landing...

Because of water retention going from +30 Deg down to sub zero in less than 15mins.

But that's just a starter.

I am sure those that deal with these materials will have more of a clue. But "fairy liquid" dishwashing liquid of choice for mounting tractor and car tyres was banned 40 years ago in Aberdeen for oil work.

RE: Alaska Airlines flight forced to make an emergency landing...

Quote (Don't know that much about it.)


I've been keeping up with it... no heads rolling...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Alaska Airlines flight forced to make an emergency landing...

Ok soap and Al.

This is digging back years of memory.....

Doesn't Al ions swap with the Na and it turns into some stringy none soluble muck?

You definitely shouldn't use normal soap on Al hydraulic fittings.

RE: Alaska Airlines flight forced to make an emergency landing...

Alistair,
the use of "dish soap" is not allowed by the process specifications. some "genius" apparently decided that installing the seals was too difficult/time consuming and not meeting cycle time goals so they decided to just use dish soap to make it very slippery. its a non-compliance. probably not the only one in the factory.

RE: Alaska Airlines flight forced to make an emergency landing...

They were using soap on the door seal, not hydraulic fittings. Soap reduces the freezing point.

It's clear that someone in QC should have flagged someone in QA who should have stopped the practice and flagged program management to get some engineers to do the research into whether this was an appropriate material or not.

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
'Dawn' dish soap is what they use to clean crude oil off the feathers of waterfowl after a tanker mishap or an oil spill in a wetlands area. It also works pretty good on your dishes and my wife uses it as hand soap in our kitchen (we have a dispenser installed next to the sink, which can be used to either dispense little soap when cleaning something or when you need to wash your hands).

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Alaska Airlines flight forced to make an emergency landing...

(OP)
This thread was getting a bit long and slow, so I've started a continuation thread, which can be found at:

https://www.eng-tips.com/viewthread.cfm?qid=517400

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

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