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Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]
16

Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

(OP)
This post is the continuation from this series of previous threads:

thread815-445840: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 1]
thread815-450258: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 2]
thread815-452000: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 3]
thread815-454283: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 4]
thread815-457125: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 5]
thread815-461989: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 6]

This topic is broken into multiple threads due to the length to be scrolled, and images to load, creating long load times for some users and devices.
If you are NEW to this discussion, please read the above threads prior to posting, to avoid rehashing old discussions.

Thank you everyone for your interest! I have learned a lot from the discussion, too.

Some key references:
Ethiopian CAA preliminary report (Link is now broken. See PDF download below, 3 MB)

Indonesian National Transportation Safety Committee preliminary report

A Boeing 737 Technical Site

Washington Post: When Will Boeing 737 Max Fly Again and More Questions

BBC: Boeing to temporarily halt 737 Max production in January

www.sparweb.ca

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Sparweb)


I still contend that the "grandfathering" rules and the system design rules are adequate,

The structural side of things I agree with you...

The data flow and human machine interface is some what lacking if not none existent.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

(OP)
You know, there are enough things going on that there could be some rule changes that come out of this. Even if most rules don't change, and even if the final conclusions show that there was a failure of enforcement, there could still be rule changes in the pipe. Or maybe policy changes or some other high-level reorganization.

From the loads perspective, the total travel in the trim system and the pilot's control are "almost" unchanged since the beginning, possibly not ideal but hard to get yourself into a dangerous amount of trouble. Then the new thing was installed and suddenly you could get in a lot of trouble, fast. The design rules that require system safety analysis and failure mode analysis are intended to reveal these kinds of dangerous situations so that the design can prevent the danger from happening. Concealing that dangerous situation is what makes me say there was an enforcement and integrity failure.

Now that you mention the human-machine interface, I remember a discussion that has since faded. The overwhelming load of warnings and unexpected control forces that the pilots in both cockpits faced led to confusion - becoming an obstacle to both reacting to the situation and accomplishing the emergency procedure. Here is a place where the Joint Task Force report did, I believe, identify a short-coming in the design rules. Cockpits are growing in complexity, and the design rules are not addressing the level of automation that now exists.

www.sparweb.ca

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Who remembers that old Nat King Cole song, "Straighten up and fly right"?
While the regulators are trying to justify and certify some sort of bandaid on a bandaid on top of the bandaid called MCAS, I still think that they should be looking at how their regulations allowed the plane to be built in the first place.
They should have tried harder before MCAS not after MCAS.
When I first suggested doing what it would take to move the engines the suggestion was shot down.
Too tough to certify.
Take too long.
Cost too much.
May invoke the need for more training.
Instead, Boeing management and the Boeing culture tried to "manage" a solution.
How much time and money was wasted by Boeing before they realized that honeymoon with the FAA was over and they could no longer game the system?
Consider the loss of both time and money so far and the future losses yet to be incurred.
Remember the start of the cancelled orders.
Can anyone still argue that moving the engines and so fixing the root cause would be too time consuming or expensive?
It's never too late to do the right thing.
Hey Boeing; Straighten up and fly right!
Given the internal memo about designed by clowns, supervised by...

Some of the lyrics are appropriate.
"The buzzard took the monkey for a ride in the air
The monkey thought that everything was on a square
The buzzard tried to throw the monkey off his back
But the monkey grabbed his neck and said "Now listen Jack"
Straighten up and fly right
Straighten up and stay right
Straighten up and fly right"
https://www.youtube.com/watch?v=6fVaP6dM1fs

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Spar that's exactly what I am on about.

But with the current grandfather rules there is nothing to enforce adoption of modern tech such as a ECAM system.

The loads on the trim system have changed. The stab is much bigger on the Ng and max and also the trim wheel has got smaller plus has the speed trim system constantly running so the thing never normally stops moving. But I see that as more of an issue with human machine interface and being able to spot there is a problem before it's unrecoverable.

I agree with you that the enforcement and integrity also has issues and needs addressed across the whole industry including training of pilots, ATC, operations maint etc etc.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (waross)

Instead, Boeing management and the Boeing culture tried to "manage" a solution.

It's more like Boeing management set the engineers to a problem having arbitrary constraints and no solution: Design and ship X number of planes at Y cost on Z date with bigger engines, no pilot training, and no redundant AOA sensors. All that on top of legacy and grandfathering baggage we know little about. When management discovered the problem was unsolvable they used their corporate advantage to push it through the regulators and make the internal engineering objections go away.

I have to believe that there are many successful airframes that are unstable somewhere in the flight envelope without trim tabs or software or pilot intervention. The bigger engines alone did not make the problem unsolvable. If the engineer's had simply been allowed to install redundant AOA systems none of us would ever know anything about MCAS.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (charliealphabravo)

...make the internal engineering objections go away
Usually the objections go away on their own.

You got to know when to hold 'em
Know when to fold 'em
Know when to walk away
Know when to run.
- Kenny Rogers

I wonder if there were engineers who sensed issues in the management environment and decided best to be somewhere else.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

(OP)
This doesn't seem like the right direction to be going:
https://www.bloomberg.com/news/articles/2020-03-05...

At issue in the article is the suggestion to allow pilots to shut off the stick-shaker.

Since the hazardous situation comes about when erroneous information to several control systems tricks them into mistaking the AoA for an extremely dangerous attitude, triggering the stick-shaker, the solution seems (to me) to fix the inputs and the error-checking in the software, not to let the crew shut off the warning.

This is another point about the reliability and "design assurance level". The odds of a false alarm in a critical system must be extremely low. If anyone in any regulatory agency is still taking about how to just "live with it", then it might be because Boeing is NOT coming up with a solution that guarantees an extremely low false-alarm rate.

Which implies they haven't yet licked the problems of trim excursions or inadequate sensor reliability.

www.sparweb.ca

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Just stop it. You cant move the engines or change the landing gear length without redesigning the entire airframe. Boeing should have designed an all new aircraft. But mgmt chose not to so here they are with this mess.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Its normal to be able to kill the stick shaker system. In fact I am struggling to think of another aircraft type that doesn't have it. Problem with the 737 is it has no buttons to do it. Q400 we have two buttons one for each side which doubles as attention getters. Press the one flashing and its gone. 737 you have to go find a CB' to pull. I have my doubts you could do it via the CB panel when all hell is letting loose. It would need a couple of buttons, if not 4 infront of the pilots. The 4 buttons is what most other aircraft have. 2 infront of each pilot.

If it is firing incorrectly its a complete pain and a huge distraction. I have had to kill the system maybe 5 times in 17 years. But never on the Q400.

Stick shaker setup in my experience is two completely independent systems one for each side. And when both trigger together it arms the stick push system. If just one system goes you just check your airspeed pitch and power setting and if those all match then you cancel it. In fact its the main method of establishing that there is something wrong with the AoA/stall system. Each side has its own cut off so you even know which side is broken. Once killed you then down grade to only one stick shaker and the stick push is gone. But you still have some redundancy. Stick push is inhibited below 800ft rad alt anyway. 737 doesn't have a stick push system.

There is a bit of history over Stick pushers anyway. The FAA was dead against them for years and they were only fitted to high T tail aircraft which had the issue with super stalls. Now it allows them. Flyby wire don't have them they have software protections called various things such as Alpha floor protection etc. the main reason for this is because the stick pusher shoves the nose down with something like 55 lbs of force and the nose goes way below the horizon and it is utterly impossible to do the old school FAA preferred stall recovery with less than 100ft height loss.

This all revolves around the difference between US thoughts about stall recovery and the rest of the world. But mainly the differences between US and UK thoughts. This was covered in the first thread. IN the US the emphasis on stall recovery was to lose as little height as possible. So what people tended to do was power out the stall and try and hold the nose up as much as possible which then meant 5-10seconds of flying with stick shaker on. Where as UK we were always taught that the only way of recovering was to reduce the angle of attack. Power was a bonus. So for us its pitch/unload, roll wings level then power up in a controlled manner so you don't get a secondary stall. US it was bang the power in and then fight with it to try and stop height loss which usually resulted in a roll coaster ride with multiple secondary triggers of the stick shaker. if you did it just right you would ride the stickshaker trigger with pitch until you were positive climb then let the aircraft accelerate. In the last 15 years after multiple NASA studys and FAA they decided the UK method was actually safer and for the average pilot on a average performance aircraft there was minimal difference in height loss so have gone with that method. But there is still a lot of resistance within the US pilot community of examiners. Usually cantered around what if you stall at 500ft. Which is a load of nonsense because everyone is stabilised at 1000ft these days. So I expect this is the old school FAA procedure advocates fighting to maintain what they think is best. And they are full of shite on the subject and are just fighting a rear guard action that they were teaching nonsense for 50 odd years about stalling and upset recovery.

So most if not all other none Boeing aircraft types on the N reg have it. But the FAA say it would be a bad precedent to allow pilots to be able to kill such a safety critical system. Which they want to allow to be used with a 2 sensor system which is deemed none catastrophic by the simple fact that its not require to be DAL A certified. So is it a safety critical system or isn't it? Sounds to me if they argue to much on the subject they are looking at forcing Boeing to fit a 3rd AoA sensor. I suspect Boeing will tell the FAA to shut up and its easy enough to fit a button and relay to kill the power to the stick shaker motor.


While I agree that critical system design assurance should stop the triggers there is only so much you can do with two sensor voting. Which is why airbus went 3 AoA sensors very quickly. I really can't see how they can get anywhere near DAL A with only 2 sensors. And it will be impossible to get DAL A on the 737 max. And even if they could manage it the amount of changes required would put it firmly into new type rating for all the pilots which will be 2 months of training and two separate training cycles if you want them to fly NG and MAX.

Boeing will be going round in circles now and every solution will just cascade more items down the tree.

The utter silence on the wire loom issue from Boeing and Regulators is the most telling sign for me what the current biggest stop issue is.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]



Just as an example this is my current workplace.

The red circles are the system killers.

Next to the clock we have Sticker shaker and elevator trim kill buttons. Stick shaker I have covered, The trim if it runs for more than 3 seconds continually then a aural alarm sounds and that button lights up. You press it and the trim system dies.

Next along to the right is Gpws test buttons and mute. Which we can use to kill certain EGPWS warnings which occur when we have flap jams and various other none normal configurations.

The 4 horizontal buttons are for killing the spoilers and rudder pcu's and de pressurising those systems.

But all the killer buttons are directly in the field of view you need a fraction of a second to identify and kill and your eyes hardly move away from the primary flight instruments.

The blue are the attention getters to get you to look at the CAP panel one for critical warnings and one for cautions. The black square just above the windows and below the light switches is where all the warnings and cautions come up and we call the CAP . Its normal to operate with this black ie no lights showing. look there and you see what light is showing then look at the panel index in the back of the QRH and it takes you to the right page.

Now the 737 max grandfather cockpit.

It has the caution buttons alerting you to something wrong at the ends of the glare shield but no centralised CAP panel to see what's wrong, you have to search round the cockpit to see which system is showing a light. No 737 version has a CAP panel.

Now the A220 doesn't have a CAP panel either, it has a 5th screen below the flight instrument screens which is the ECAM system which not only brings up the warnings but also brings up the checklist as well.

The 737 MAX really is a geriatric Frankenstein of old tech and new. Items which have been industry standard for 50 years are missing but then its got the latest telly screens. You will notice in the ceiling the analogue pressurisation system circled in red. That contraption has been responsible for more deaths than the max has over the years. Pilots have been wanting rid of it every since the first 737 came out the hanger. Its analogue pressure bellows differential pressure controller. It gets screwed up by water in the system leaks and numerous other things annoy it. Most planes you just set the arrival altitude during the pre start checks. Have a look at it going through 10 000 ft and never think about it. That thing if some one farts in the back it sets up an oscillation in the outflow valve. Just been emailed by a mate that read this and he says that the NG they went digital cabin pressure control. But in true Boeing fashion instead of having one system and a different method for backup it has gone to two systems and they swap over between flights aka the FCU method for the AoA system MCAS 1. Its still an utter pain because each controller is on different electrical buses. So half way through a electrical issue you can suddenly find that you have lost pressurization and the rubber jungle has been dumped in the cabin. But it depends which cabin controller is the live one what happens. But there is no documentation on it so its word of mouth that you have to watch for it during an electrical failure. So its still not great but better than before.


But the main thing is no cap panel which even the Jetstream 31 had which is 45 years old now, Hanley Page who designed the Lancaster bomber put a CAP panel in the heap. Attention getter, look at the panel then straight to the system which has the problem then get the qrh and locate the page using the cap panel index. 737 max attention getter, then complete scan of the panels to find the offending system. Then find the QRH, then find the right page in a 1.5" thick paper book using a list index and no way of killing at least some of the noise and distractions going on.







RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Looks like Boeing is going to get hit with a 19 million fine for fitting uncertified sensors to 800 Ng and Max's. Not alot in the grand scope of things. Only 24k per airframe which I am sure they made more profit on the HUD system than the fine is. And the bonuses will have already been paid. But I suppose it makes the FAA seem like they are doing something. If it wasn't for the max I am sure nothing would have been said or done.

To be honest the FAA should be giving themselves a similar fincial hit.

As it appears Boeing has had absolutely minimal oversight for quiet some time.

And the first of many US investigation reports are out.

Pretty brutal to both Boeing and the FAA.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

All of the committee activity on the 737 MAX
https://transportation.house.gov/committee-activit...

Press release House Committee on Transportation
https://transportation.house.gov/news/press-releas...-

Report - The Boeing 737 MAX Aircraft: Costs, Consequences, and Lessons from its Design, Development, and Certification
-Preliminary Investigative Findings- Prepared by the Democratic Staff of the House Committee on Transportation and Infrastructure for Chair Peter A. DeFazio, Subcommittee on Aviation Chair Rick Larsen, and Members of the Committee March 2020
https://files.engineering.com/getfile.aspx?folder=...

Fred

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The bit I don't get from things coming out is that they have now decided that the MCAS activation would only happen "once".

But once what? Every time the AOA sensor goes back into "normal" range and then back again into high AoA? A faulty sensor or wiring break might flip between these?

Once a flight? - But then what if it's needed more than once a flight in correct operation?

How is the overworked FCC going to keep track of all this?

They say they will disable MCAS if the AoA sensors disagree by more than some value. But again, if the aircraft is actually doing a a manoeuvre which needs MCAS to operate how is that going to work?

As ever what seems to be a solution has added complications.

The disable stick shaker article seems to imply pulling circuit breakers - that's not going to work surely. Far too easy to pull the wrong one or for it to become SOP to routinely pull the things.

This saga doesn't seem anywhere near resolution just yet.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (SWComposites)



Just stop it. You cant move the engines or change the landing gear length without redesigning the entire airframe. Boeing should have designed an all new aircraft. But mgmt chose not to so here they are with this mess.
The first mistake was selecting an engine placement that resulted in unacceptable flight characteristics.
The second mistake was trying to cover up the first mistake.

I understand that the landing gear was redesigned.
I understand that the wings were redesigned.
If the pickle fork is the same as on the NG then it should be redesigned.
The forward engine size and placement significantly increased twisting forces on the wing.

The barrier to doing it right was not technical, it was a marketing decision that there must be no more than I-Pad training.
That barrier is now gone.
Another barrier may have been financial. Don't spend any money.
Well now the largest single shareholder of Boeing is no longer the CEO and the new CEO is blaming the previous CEO for much of the mess.
That barrier may be crumbling.
We are well past the point where it has cost more to cover up the problem than to fix the original problem.

Quote (Wiki)

In March 2010, the estimated cost to re-engine the 737 according to Mike Bair, Boeing Commercial Airplanes' vice president of business strategy & marketing, would be $2–3 billion including the CFM engine development. During Boeing's Q2 2011 earnings call, former CFO James Bell said the development cost for the airframe only would be 10–15% of the cost of a new program estimated at $10–12 billion at the time.
So, losses of over $18 billion trying to patch MCAS, when a clean sheet was estimated at $10 B to $12 B.
In hindsight, repositioning the engines, including any redesigns of other components would have been much cheaper.



Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

In some ways I don't think it was ever about the cost of a clean sheet.

It was purely time and training.

They have succeeded with the time factor because they have the orders and the airbus order book is full for over 7 years so 737 customers are basically screwed and have to stay with Boeing.

The training side of things Air Southwest has a lot to answer for.

They have an extremely specific EFIS setup which nobody else uses.



Its telly screens but analogue instrument representation. Nobody else has it. Its so they used to only do 1 sim session for all types per crew and that covers them for classics and NG. But they got rid of the classics in 2017 so I don't really understand why they want to stick with it. In Europe they used to cycle between the two so one 6 monthly sim session was in the NG and the second in the classic. So they left the EFIS as it was meant to be.

But ASW run over 700 737's with an order for 300 Max's. The 1 million per aircraft or ipad training is no small part of this fiasco. Be interesting to see if they actually enforce it.

An Article in the WSJ seems to indicate a statement about the wiring looms is due form Boeing and the FAA soon. And they will have to move them in the ones already produced and when production starts they will have the new looms. Which is going to penalise the owners of the ones delivered and of those sitting in the Boeing parking lots.

So all the planes produced so far will require.

1. Mcas 2 uploaded.
2. Rewired.
3. FOD inspection to remove all the crap in the fuel tanks etc.
4. All the cowls checked for lightning conductivity check thanks to them hand tooling them to get them to fit.
5. Removal from storage maint.
6. Removal from storage inspection.
7. CoA physical inspection.
8. CoA paper work audit.
9. CoA test flight.
10. There will be snags on all of them after the test flight which will need fixed.
11. Another test flight.
12 CoA issued
13 Customer inspection and test flight.

There may be other things have to happen as well but they haven't released those problems. And the Ethiopian crash report may also highlight other issues.

But realistically I can't see the max being flown for revenue in 2020.

The pulling of CB's to isolate systems unfortunately is quiet common, and your right it is a pain in the bum. The cb panels are set up in a grid and when you get to a point in the checklist it will say LH upper DC essential panel pull CB D8. And you find it and pull it. Some company's put collars on the CB's that are mentioned in the QRH so they are easier to find and easier to pull out. Its not a problem in the q400 because they are all easily reachable and you can see them from your seats. And there is only 3 from memory... and only one major one to be pulled in flight when your doing an emergency landing which very rarely happens, only when you have a gear unsecure normally. Bigger cockpits such as 737 and you have to unstrap to be able to reach a lot of them. During flight your not meant to reset CB's so the only requirement is to be able to see them to see which one is popped.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I have my solution. You won't see me flying in one of them, certified or not.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

So is that 5 screen version a 737 max but rigged for South West Airlines only??

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

That's a NG in the picture butchered for southwest.

And it's official now Boeing is going to have to rewire all the Max's that have been produced. They had been playing down the extent of the issue. There 7-8 bundles in the avionics bay and 5-6 in the tail. And two fusalage length bundle's. So that's not a small job to sort out.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (SWComposites)

...Boeing should have designed an all new aircraft. But mgmt chose not to so here they are with this mess.

It was more their clients than management who pushed for a warmed-over 737. The airlines didn't want to stock an entirely new set of spares and retrain all their pilots and technicians.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Hpaircraft is correct.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Seriously? Blaming the clients?

There is only one party at fault and it's not the gov. Boeing got where they are because they abused regulations and procedures and the years of previous trust they had built up that opened the path that led them to these result. Its letting them get away with it that is squarely on GOV shoulders, but you really can't say much more about that. The rooster is roosting right where it should be. They rebuilt Frankenstein and all the parts don't add up at all.

Educating clients is one of the hardest things an engineer has to do, but it needs to be done, certainly more times than I'd like. I've had to draw lines in the sand and I lost a few battles, but I won the war so far.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (ax1e)

...There is only one party at fault and it's not the gov...

Oh, please spare us the monochrome. There is plenty of blame to go around.

Boeing came up with an entire family of airframes designed around the latest CFD optimizations and high-tech composite construction technologies. One of them became the 787 Dreamliner. The one that was intended to replace the 737 went nowhere, because clients just didn't, and still don't, want it. What they persisted in asking for was an updated 737, and that's what Boeing made for them--just not very well.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

ax1le it is how I understand it as well.

But as hpaircraft says there is plenty of pressure coming from multiple directions pushing towards the way it went, internal and external.

The resulting system design and certification compliance though is all Boeing. The letting them get away with it and certifying an aircraft which shouldn't have been is the FAA.

ASW has over 700 and Ryan air over 300 737's. Both were expecting to expand significantly using the MAX I think Ryan was projecting 520 aircraft by 2024 in its airline group. So between the 2 of them its 25% of sales.

Ryanair want a high density model with additional emergency doors and shall we say variable Max takeoff weight. Which is a fiddle for airways charges in Europe. Basically they recertify the aircraft every time it fly's to a new max takeoff weight to reduce Airtraffic control charges. And I presume it will also want internal front steps like its NG's have. Its model has not been certified yet with the extra door.

It doesn't want to use baggage elevators either. They currently don't use airbridges either if they can get away with it.

Realistically there should have been only one reply to Southwest with its instruction to bastidise the EFIs system so its screens show analogue instruments. And its should come from the EFIS OEM, Boeing and FAA. Sex and travel.

Another stupid safety fiddle out there is not maintaining the avionics to dual FD low vis standards. Instead they make the Captain fly a manual approach in low vis using the HUD which is only fitted on the Captains side and only they can see it. So the FO doesn't get a set of certified low viz instruments to look at. Which completely defeats the whole idea of multicrew and monitoring backup. This is the system the fine is about using none certified sensors. But the fine is 24k per airframe and that's likely to be less than a years cost of dual FD low vis Autopilot maintenance.

This fiddle has been involved with a few crashes the flydubai being the main fatal one, but there are numerous incidents where things have got hairy if there has been a go-around performed. Quite why your allowed to do a single pilot CAT II/III approach using a secondary system without the primary system being compliant for the approach I have no idea.

BTW the airlines won't have learned form this and it won't stop them from trying to find every single loop hole they can to reduce costs. And when it goes wrong they will always say its not our fault they let us do it. See our ops manual was signed off by the FOI its legal.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Thanks Alistair. Adding emergency doors is the best idea they have there.

It looks like all of that is leading to a pilotless flight deck.

I flew Ryan Air one time maybe 15 years ago. That won't happen again.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Its not to be honest because the only reason why they want to do it to ram more people inside it.

They won't be fitting more toilets.

They won't be upgrading the air handling system for the increased numbers.

They will use a load of fit sporty types and pay them a huge bonus if they succeed to do the emergency evacuation test emptying the aircraft in under 90 seconds with 50% of the doors inop.

There will be broken arms and legs and also countless numbers of skin abrasions.

They have been saying pilotless cockpit since I was 10 years old 38 years ago. And I don't expect to see it in my lifetime. The aircraft technical side is one thing. Mother nature is another. The fitting in with everyone else up there is yet another detail. We have driverless trains and they are relatively simple, but they are still not main stream.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

this isn't the final report but an interim report because they have to produce something inside a year.

Its a bit of a weird interim report to be honest because it has a lot more stuff in it than is normal for one of these.


Haven't read it properly yet so will comment on the content later


http://s3.documentcloud.org/documents/6801178/ET-3...

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Right it stinks.....

No CVR,

No training records.

No human factors.

Nothing about the fitting of the Sensor and the technician.

The control forces though are interesting and show a surprisingly small window when you can trim manually.


I hope that they have just copied and paste parts of the full report and those sections are in the final report. If they are missing its pretty much a whitewash to deflect away from Ethiopia's regulator and the airlines failures. Which of course will have completely the opposite effect internationally.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

A couple of things which may be in earlier threads which I had forgotten:

1) The MCAS operated on the master FCC. This is not affected by the flight director switches and just alternates without any apparent ability to know which one is active or any means to switch to the alternate FCC. So a bit like the radio alt error in Amsterdam, the pilots had no real idea that using the other FCC for autopilot didn't stop the other one commanding other parts of the plane using duff info. By this simple switch to make all flight control run through the other FCC once they realised the captains one was going haywire could have stopped all this. I wonder if they will add this or is this not a "done thing"?

2) The feel force on the stick uses the AoA input to provide force and close to stall this force increases (doubles). The ET pilots were trying to hold nearly 50kg between them just to climb slowly / stay level. They did this for 5 minutes.

So yes there's not much if anything on those issues but quite a lot on the design of the airplane. They also piggybacked onto the NTSB recomendation for safety assessments.

I do think though that the current Boeing CEO essentially saying US pilots wouldn't have crashed is rather rich. If you sell aircraft to non US operators then you need to make your aircraft capable of being flown by non US pilots.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I think the none US pilot stuff has been blown out the water when they put the FAA boss in the sim and then followed it up with a cross section of 737 drivers from around the world but mostly from the USA.

Apparently from pub chat its was a colossal screw up of an exercise. Boeing were all in favour of it in the beginning, thinking it would prove that home grown would conclusively prove that it was a issue with foreign training and standards. But it was both barrels of a shotgun through the feet exercise. hence it was reported having happened but then never mentioned again by Boeing.

There was apparently no difference between the pilot groups. The majority though failed to complete the exercises using the Boeing documented procedures. They pretty much made it up as they went along, which to be honest isn't that unusual in the sim. If the procedures are designed sensibly then airmanship and logic should provide 95% of the procedure without even looking at the QRH. Nobody crashed but there was some rather sporty recovery's which required the sim to be "maintained" afterwards. Which usually means there has been colossal ram switches of direction and movement and the sweat box has gone in a sulk through over heating or just bits breaking. Which is usually an indication that the plane was out of control and luck played a huge part in the not crashing.

Hence the reason I believe the FAA boss is saying he will personally fly the machine after doing the required training. And also the reason why they are not getting any exceptions.

The media spin machine is kicking in again though over the wiring loom issues and the same people who were saying it was all the pilots fault are shouting and screaming that if the wires need to be moved then the NG needs grounded as well. And if the NG can continue flying then the MAX doesn't need its wiring looms changed. I don't think they have a hope in hell of changing the decision though because the FAA would have to go it alone then, as the other regulators won't accept it.

There is also talk of a MCAS activation warning light and also a STS activation light. Which should be in theory be simple with a change in software and an icon on the EFIS. But that would then require the software to be DAL A which it isn't. And MACS is definitely considered catastrophic so even just a warning light needs redundancy so it can't just be hung off a relay with a software trigger, so they will have to come up with 2-3 different ways the warning can be triggered. As you can imagine Boeing is dead against such a requirement but I suspect it will happen.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (LittleInch)

I do think though that the current Boeing CEO essentially saying US pilots wouldn't have crashed is rather rich.

Are they still pushing that user error argument? Sheesh...

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

That may indicate which orifice his head has been lodged in for the last 6 or 8 months.
On another note, remember the gas explosions in Massachusetts?

"BOSTON (AP) — A utility company will pay the largest criminal fine ever imposed for breaking a federal pipeline safety law — $53 million — and plead guilty to causing a series of natural gas explosions in Massachusetts that killed one person and damaged dozens of homes, federal officials said Wednesday.

Columbia Gas of Massachusetts has agreed to plead guilty to violating the Pipeline Safety Act and pay the fine to resolve a federal investigation into the explosions that rocked three communities in the Merrimack Valley, north of Boston, in September 2018.

"Today’s settlement is a sobering reminder that if you decide to put profits before public safety, you will pay the consequences," FBI Agent Joseph Bonavolonta said.

The company said in an emailed statement that it takes full responsibility for the disaster.

“Today’s resolution with the U.S. Attorney’s Office is an important part of addressing the impact," the company wrote. “Our focus remains on enhancing safety, regaining the trust of our customers and ensuring that quality service is delivered.”

The company's parent, Merrillville, Indiana-based NiSource Inc., has also agreed to try to sell the company and cease any gas pipeline and distribution activities in Massachusetts,
according to court documents. Any profit from the sale of Columbia Gas of Massachusetts will be handed over to the federal government.
I doubt that the FBI will be as tough on Boeing.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

AH, you were overdue for a star and I loved "both barrels of a shotgun through the feet exercise"! lol

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Tomfh)

Are they still pushing that user error argument? Sheesh...

Seems like it to me. The arrogance seeps through.

I think they made more than one mistake as well.

From the NYT articles with the new CEO linked above by sparweb.

"When designing the Max, the company made a “fatal mistake” by assuming pilots would immediately counteract a failure of new software on the plane that played a role in the Lion Air and Ethiopian Airlines accidents. But he implied that the pilots from Indonesia and Ethiopia, “where pilots don’t have anywhere near the experience that they have here in the U.S.,” were part of the problem, too.

Asked whether he believed American pilots would have been able to handle a malfunction of the software, Mr. Calhoun asked to speak off the record. The New York Times declined to do so.

“Forget it,” Mr. Calhoun then said. “You can guess the answer.” "




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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Watch this space over the next few weeks. I suspect Boeing maybe loosing up to 20% of its orders for the MAX due to airlines going bust...

SpiceJet is looking dodgy and Jet airways it only a matter of time now. Between them they have over 400 airframes ordered. Which is 8% of the total orders.



And airbus will be getting a fair few orders evaporate as well.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

And of course if Airbus's backlog gets smaller due to out-of-business airlines the remaining airlines with Boeing orders would more easily be able to cancel & order from Airbus.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Littleinch)

But he implied that the pilots from Indonesia and Ethiopia, “where pilots don’t have anywhere near the experience that they have here in the U.S.,” were part of the problem, too.

Amazing. First he comes out swinging at Muilenberg for producing a poor quality plane, and now he's blaming the pilots for crashing the plane.
 

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There has been absolutely nothing changed about the finger pointing from the day the lion air crashed.

Your talking about half a century of standard response to any crash. In fact this is pretty much the first time its failed to work blaming the pilots since the Comet.

The only other time it hasn't happened was with the Concorde and that was because the OEM wanted to kill it off and stop it flying. And it was the pilots/airfrances fault in that case.

Even once they get this Frankenstein beast back into the air there will still opinion circulated that the new revised and legal aircraft is not as good as the original by Boeing. And the changes have ruined it.

The only thing that quiet a few care about is the Boeing stock price and the hit this has caused to their pensions. The people being killed they have zero interest in.

Anyway this corona virus is going to hit the entire industry harder than 9/11 and its going to last longer as well.

Buckle up, its going to be a long bumpy ride.

Just after posting this I open up a news feed and see the USA has banned all travel from Europe but with exemptions from the UK. Right next to it is an article that Tom Hanks and his wife have it. Talk about shutting the barn door after the horse has bolted.

And they are talking about unpaid leave and redundancy's at work for me.... lets see what happens.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

(OP)
I never know if I sound like an apologist when I say this stuff...

I seriously doubt that the stick-and-rudder skill of the average pilot has actually improved over the last 4 decades. Probably the opposite. But that's the kind of skill needed to (a) handle the original 737's in the '60's, and (b) react quickly when the automatic stab trim goes haywire, and (c) distrust the electronics deeply enough to even consider the possibility that the computer may have lost its mind.

Also don't forget what is the cause of 75% of all air accidents - the pilots. Not throwing any of the valuable members of this forum under the 'bus, so to speak, but they are humans and thus can make mistakes. The statistics themselves are hard to trust - they are based on complicated scenarios that aren't usually repeatable, but quite often a human error comes up. Just the other day a preliminary accident report crossed my news feed about a pilot and co-pilot so completely out of sync with each other that one advanced the throttle while looking down at his checklist while the other was trying to pull them back because he was looking out the window seeing that they were drifting off the centerline of the runway. The end result was they both got 1/2 of their wish, and the plane spun into a snowbank with one engine at idle and the other nearly full power. This kind of tomfoolery happens much more often than it should.

www.sparweb.ca

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The older aircraft were harder in some respects and you needed and required more of an engineer's mind set. For dealing with stuff. But all of the time you knew exactly what the machine was doing. But easier in others because what you see is what you get.

The people flying them were different as well. Most of them came into civilian flying with a military back ground.

These days it's straight from uni/school for alot with zero life experience.

I completely agree with spar about pilots being the biggest variable and the cause of the majority of accident's either completely or as a major contributor.

But then again there is no statistics on what a pilot does successfully sort out day to day. Automatics are great load reducers. They also save alot of fuel. But every single approach will have some sort of pilot input to get to the ground. Be it to temporarily select heading and Vs on a ils when the beams start to wobble due to the 4 aircraft ahead or not react to a huge gust and chase the airspeed.

I don't have a solution. I know the direction we should be going in which is a better understanding of the current humans becoming pilots, Their thought processes and instinct reactions and thier limitations globally. And then design for that. It's a start and other things will surface along the way but continuing with using 50 year old presumptions which where never completely correct in the first place history will only repeat itself with these human machine clashes.

Handling skills have decreased depending on what section of the industry your in. Long haul jet pilots suffering the most. Some only doing 3 landings a month. The company's are actively preventing manual flying in day to day operations.

Us turboprop dash trash types. We still get plenty of stick time. 4 sectors a day and 20 working days a month means we are banging in. Literally that is, just got a fdm email about my first officer s 1.79g landing. But anyway I land 40 times a month and watch for another 40. The airport's we fly to will allow us to do visual approaches so we do them. Think i did 4 approaches from 10000ft to landing with no flight director or autopilot in the last month. In summer it would have been more.

So there is a huge spread of stick skills as well for designers to deal with.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

This is an interesting article.

I remember the up roar around the time of the Airbus selection cancellation.

Why on earth would you want to fly the plane and the boom at the same time? Btw in the UK we don't use booms our planes have to prod a basket.

But it's not just the max that Boeing is dealing with.

https://www.nbcnews.com/think/amp/ncna1153671

The starliner has issues as well.

Is there anything they don't have issues with?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

YES FUEL PRICES. HOLD ON AIRLINES. HELP IS COMING.
https://www.cnn.com/2020/03/08/investing/oil-price...

Our (Petroleum/products) industry is doing everything possible to support our aviation clients. So much so that we may put ourselves out of business pretty soon in the process. $31/BBL you just can't beat it, even with a stick. Unfortunately we all may be out of business soon, if not tomorrow. Expensive shale oil cannot even compete with solar cell power any more, never mind that super-cheap, conventionally produced oil, from Saudi Arabia and Russia. Woooo! Who could have seen that coming? Thanks for your BILLIONS of capital that it took us to get us there, BTW. And ... Ah, You won't be seeing that again.

Hopefully the airlines (and the rest of you as well) will finally reap the benefits of cheaper jet and other fossil fuels on the way in the immediate future and use those BILIONS OF SAVINGS to keep the flight crews flying, and ground service staff gainfully employed during their time of crisis, all those hedge funds and oil traders going, and perhaps contribute to the many faithful oil and gas companies, and their workers, that contiuously endevor to support the world, even to their own detriment. Or at least not complain too much if we ever get a fair price again for our stuff. Tell me. What other industry is so adept at developing new technology and so competing so fiercely in fair world market that they force themselves out of business? It certainly makes the dangers of drinking your own kool-aid perfectly clear. Can we talk bail out?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Well the low oil price will have several much larger effects for me coming from Aberdeen Scotland. What's the current North sea break even point?

There is no point burning fuel when nobody is travelling. I am hearing 50-60 pax on a 180 seaters which most of the loco's run. Yes fuel is a large part of the turn over of all airlines but sub 40% load factors the fuel could be free and it wouldn't change anything.

And there is nonsense going on that aircraft are having to fly empty just to keep slots in the major airports such as Heathrow. These slots are worth millions each and the airlines don't want competitors to get them so they fly empty aircraft. Hopefully that will be suspended in the next few days.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Well that's the type rating cancelled... And redundancy notices going out.. I am lucky and still have a job....

A bit of pilot humour...




Another thought is when to buy Boeing stock? I reckon 100$ to set my buy for.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

That Boeing tanker story was really interesting.

How much of Boeing’s recent share rise over the last decade was due to this deal?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

(OP)

Quote (Alistair Heaton)

...there is no statistics on what a pilot does successfully sort out day to day...
Like the goalie at a hockey game. There's a bright red light that comes on every time he makes a mistake. But he gets 100+ saves during the game and hardly anyone notices or keeps track.

The other point, about skill in general, is such a tough nut to crack. Pilots, drivers, computer programmers, architects; everyone should have a skill, but is it valued as much as it should be? I'm increasingly convinced that the entire mentality of both Western AND Eastern people is completely inadequate to the task. Not referring to technological sophistication, exactly. In some ways; throw enough computation at a problem and you can get any machine to do a lot of things on its own. What I'm really referring to is HOW it gets them done, HOW often it gets it right, and HOW much any user can trust it. What if the whole thrust of automation and AI is just because too many people can get away with being lazy?

The Darwin award winners who die in Tesla highway crashes while napping are just the trailblazers on this path.
So many individuals around the world are convinced that convenient, simple, easy is equal to good.
Accept the stuff you read on the internet, accept the promised 20-pound weight loss just by drinking this powdered product you can order online, accept the lane-keeping reminder in your SUV, accept the form the government tax agency sent you is accurate. You got it all from a computer so it must be the best.

I spent 3 weeks in China a couple of years ago, sharing daily life with folks who have within 1 generation discovered a plethora of western technology, but not a soul among them knows how to use it skillfully. The whole time I was subjected to myopic drivers who can't see the road for the phone in their face, empty abandoned skyscrapers, electrical receptacles in the shower wall, and airplanes whose controls were assembled with stripped-thread bolts. Every moment I knew that somewhere in my field of vision there was at least one bollixed-up thing and I had to try real hard to stay focused on just one at a time to maintain my sanity. There was this constant onslaught of incompetence. I couldn't even order a snack without watching someone fumble for a tedious minute with the container. Can you imagine what kind of pilot emerges from this environment? Sorry - this subject brings out the worst in me sometimes.

I make a dedicated and conscious effort to be as skillful as possible in as many things I do every day as I possibly can. There's a moderate level of this attitude in the people around me, but precious few people in my immediate circle who actually realize that skill is an EXTREMELY satisfying part of life. Discovering a way to do something and putting it to use is great fun. Finding a better way the next time you try just sweetens it. I know some people who think this way and I admire them greatly.

When confronted people who "phone it in" or got their training from school and that's all they know, I really have to bite my tongue. I hear them complain about trivial problems - things I've solved in my life a long time ago (and moved on to bigger problems, everybody's got them) I wonder just how happy or satisfied anyone at all is with their life.

I'd better stop. Glad it's my thread so I get to pretend it's on-topic. wink

www.sparweb.ca

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I personally do think it is on topic.

But it does encompass pretty much every thread in this sub forum to some extent.

Your comments about different geographical areas and skill sets could and would be labelled racist by more than a few. But I know from experience that you are correct. Its not related to anything genetic before anyone gets upset. Its all to do with how someone grows up and what experiences they are exposed to during childhood and what is the norm in their environment.

You can find the same technically clueless people in every company in the world. Just go to the accounts or marketing departments and you will find a vast herd of them.

As for the getting satisfaction from doing something properly and getting frustrated and persevering to get better. They have started labelling traits like that medically, Autism being the favourite, 50 years ago they would have called them grumpy engineers. winky smile






RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

To Alistair's point, as soon as you hear in any discussion a participant refer to any other participant in the discussion as anything "...ist" or "...phobic", you know you are talking to someone who is either unwilling (usually through ideology) or unable (usually thru indoctrination) to reason.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

2
debodine,

I think that's a pretty extreme blanket rule to apply to any discussion.

There are lots of people who will use an accidents (such as the 737 Max) or other events (such as Covid-19) to say racist or xenophobic things based on biased prejudices or beliefs. That's a sad fact of human beings. Of course there are also people who will claim the other side is being racist/xenophobic just to try to "win" the debate.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote:


Like the goalie at a hockey game. There's a bright red light that comes on every time he makes a mistake. But he gets 100+ saves during the game and hardly anyone notices or keeps track.


Well, actually, in pro hockey, almost everyone notices, and thousands of people keep track of those percentages.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

(OP)
It didn't occur to me at the time of writing yesterday how my message could be misunderstood... thank you for pointing it out and not jumping all over me.
For the record (I feel a CYA attack coming on) I encounter a large number of people who seem to be incompetent all the time everywhere I go, and this may be a problem with me, if not as much a problem for them. There is no pattern and there is no particular trade or discipline where I see it more or less. I'm just sensitive to it and it bothers me so much that I probably tend to overreact to it more than other people do. It was the general incompetence - or better put, denigration of the value of skill - that I was complaining about. I just happened to be in China at the time that I was also immersed in a group of people who really didn't know what they were doing. I have also seen the befuddled work of plenty of down-home American, Canadian and European people in one mechanical trade or another. I also know I've screwed up a few times and those events are painful to think about. As the old saying goes "the problem with incompetence is that the supply always exceeds the demand".
Oh, and then to rub sand in the wound, I was listening to a radio show last night and then they turned to the topic of "Should we aim for mediocrity?". So you guys only got 1/2 of my rant because I boiled over again at the dinner table.

Again, I should cut this short. For therapy I think I should go read "Zen and the Art of Motorcycle Maintenance".

www.sparweb.ca

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

So now not only are boeing faced with a " geriatric Frankenstein of old tech and new " their age old desire to let the plots fly the plane and do things in short spaces of time is being attacked by the reality of pilot skills and airline desire to set everything into auto and let the plane do the work.

It seems to be a growing realisation that the automation side is now so much a part and parcel of modern aircraft flying that the pilots, especially those coming straight from school/university/pilot training academy (as the ET captain was), just don't mistrust the machine enough.

Thus this hybrid machine Boeing has in the 737 max with part manual part FBW is now at odds with the people being taught to fly it.

I wonder if it will ever get there sometimes.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The 737 carries more of a "geriatric Frankenstein of old tech and new" than we realize. It carries a thin fuselage skin approach that started with the 727. I understand that the skin is a little thicker than early model 737 (Aloha Flight 243 high cycles, corrosion, thin skin) but it still suffers more often from skin fatigue cracks than it should. Now that smoking is banned on commercial flights the airline maintenance people no longer have nicotine stains to help show cracks before they become worse (Southwest Flight 812 + Flight 2294 + a 737 yesterday with a crack on a flight from Idaho to Las Vegas).

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The ET Captain wasn't some low hours numpty.

He had slightly less than me total hours at 8122 hours. But significantly less PIC time of 1417. But 1417 PIC on the 737 is 2 years flying as a Captain. So he will know what he was doing. The FO was a different story.

He also had time on a proper old school aircraft the 757/767.

He will though have had a lot less sectors than me. ie TO/landings

But that cockpit experience is no different to a lot of loco cockpits in Europe.

I don't think they didn't mistrust the automatics, they just didn't have a clue how to sort it out because they didn't know what was going on. I do honestly myself wonder if I could have done any better. Realistically and truthfully I am not sure I could have at the time.

I can not emphasise enough how strange and utterly confusing something screwing with your controls is with the autopilot out. FBW is different story they are trained from the outset that there is stuff going on that you don't know about. Boeing sells the 737 on the fact that the pilot fly's the plane and the controls have a direct linkage to the flight surfaces. So with the MAX they went Frankenstein FBW without telling the crew and not designing and certifying to DAL A FBW standards.


And yes comcokid there is crown skin cracking issue which is surfacing just now on the NG's but nothing released yet by the FAA. That area has already got a 1500 hours out of phase inspect AD on it. But an aircraft apparently had a fast fracture failure on it 500 hours or something like that after the last inspection. So they are now wondering if just a visual inspection is enough.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Comcokid)

It carries a thin fuselage skin approach that started with the 727.
Not to nitpick, and I'm quite willing to be corrected, but I seem to recall that the downsized 707 i.e. Boeing 720, had a lightened structure that included thinner skin. And as far as I know the 720 came a little before the 727. Just for the record. cheers

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It might be more to do with acid etching becoming more main stream in the 60's.

About that period they all started thinning the skin down between the attachment points.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Some more on the crown splits.

https://www.seattletimes.com/business/faa-is-probi...

Seems to be happening to ASW a bit to often for comfort to be honest.

the Q400 early on suffered a load of gear failures. And that turned out to be an issue with maint by SAS.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Is that type of cracking common to passenger jets?
Is it unique to Boeing jets?
Is it unique to 737 aircraft?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Yes.
No.
No.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Thanks SWComposites.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Here is a bit of info for you Bill

https://www.ntsb.gov/investigations/AccidentReport...

Some are more prone to it than others. And individual models have different areas which usually go first. You will always get it with cyclic loading of aluminium eventually.

As you can see from the report manufacturing quality also plays a large role in when it happens.

Unique to Boeing jets no.... it will happened to all of them eventually, number of incidents which have occurred on Boeing products.... that is worth looking at, my gut feel from the reports I have read is that it seems to occur more on Boeing than other OEM's.

Definitely not 737 only issues they have had it on 747 and 757 as well. Both old school proper Boeing aircraft.

In theory its not a huge safety issues. Most aircraft through ram pressurisation and the engines can keep the cabin pressure for long enough to get down to 10 000ft with surprisingly large holes. Bigger than a cabin window. And they have well defined checks that should catch it.

It will be interesting to see if it is one of the aircraft that ASW got a fine for not doing due diligence on when putting them onto the N reg. So I sort of agree with SWC's answer but its not the whole picture. As I hinted at with the reference to the issues with the Q400 gear I see it as more an indication of issues at ASW maint department than a design issue.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Alastair,

I wasn't trying to throw the ET pilot under the bus, just noting that he went into the EAL aviation academy at 18 for 2 years before he got his CPL. He was then FO on 737 6 months later. The point being was that was all he had ever done.

I think and hope that one thing which does come out is a much better set of information and training to aircrew in similar circumstances. The delayed and very simple note which Boeing eventually produced was unclear and unspecific (can be used...) in the key aspect if the plane suddenly dives which was trim it back to level flight before you pull the switches (but once you let go the thumb switches you only had 4 seconds to act and it kept on doing it). The fact that it then also said you can manually trim at any time was clearly not thought through or correct or tested. Also that it worked on one sensor and the FCC which was in command and couldn't be changed.

I've just re-read the AD issued and it doesn't mention any of these key aspects - i.e. it kept doing it unless you cut the stab trim and you only had 4 or 5 seconds after getting the plane level before it did it again. Oh and the trim down would be 4 units.

If the aircrew knew then what we know now and had been trained accordingly then they should have had a better chance.

But at the rate we're going with flight cancellations and undoubted airline failure(s) the loss of the Max might not be as bad as it was a few months ago.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

His training and experience is no different to an extremely large percentage of pilots that trained in the last 20 year in Europe.

The bulk of EasyJet and Ryanair Captains will have a similar profile. The only thing different about him is that he did a stint flying long haul.

To be honest that AD stinks of lawyer input. The way they worded it is not normal. And its not as black and white as they normally are. I suspect everyone from both Boeing and the FAA that were involved in it now no longer work in either. Its main purpose was to keep the MAX flying and portray it as a pilot error. its main objective was zero responsibility of a design issue or for poor oversight by the FAA.

I would take anything from that period with a pinch of salt. Per say the AD is now obsolete as the aircraft will never fly again in that configuration.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Seattle times story)

No one was injured in those incidents, but in 1988 an Aloha Airlines flight attendant was blown out through a hole of a Boeing 737 as it flew over the Pacific Ocean.

'Hole' sort of understates it. The stewardess blew away because the plane no longer had a roof and she wasn't seated with a belt on.:

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

To be fair, I don't think a modern aircraft would have survived that with only 1 fatality.

It also had 90k sectors/pressurisation cycles.

Which is the life limit for 737's for most of the major parts such as the main spar etc.

http://libraryonline.erau.edu/online-full-text/nts...

Here is the report.

Quiet how you can't spot a split in the fuselage skin during walk round during the day I really can't understand. I can only put it down to shite standards by the crew. Ie it was bounce multi sectors and they couldn't be bothered getting out the FD to do a proper walk round. And that's old school American home boy's. I know its boys because it was purely a male job in the 80's apart from under 100 females who all worked for the likes of UA and AA and the like.

But you have to be impressed though that sort of failure and they still managed to land it and the fuselage stayed in one piece. Proper Boeing engineering. Not some Macdonald Douglas MBA designed crap like the MAX.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The window belt on the 737 classic is only good for 50,000 cycles before required modification, for the airframe to make 75000 cycles. For many examples 50,000 cycles became the effective life limit cost wise.
Relevant Boeing article on airframe limits.
https://www.boeing.com/commercial/aeromagazine/art...


A freight operator I worked for a few years ago, had an incident where one Saturday morning while washing an aircraft they found a fuselage skin crack on a 737 Classic freighter(lower aft fuse, classic acoustic fatigue resulting in chem milled step cracking), by the time they had washed all 4 airframe, three of them had been found to have the same crack. The last one of which wasn't found officially till Wednesday. It wasn't great but we didn't find it greatly concerning, having no paying punters simplifies things a lot (& we had bigger fish o fry).



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The FO on the Aloha plane was a woman, who was PIC at time of incident.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Glad to be wrong on the sex of the pilot flying.

Where does the 90k come from is that the wing spar limit?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

"If the aircrew knew then what we know now and had been trained accordingly then they should have had a better chance."

They should have known because the Preliminary report from the Lion Air crash had been published long before, there is more tech description in the FCOM (Flight manual) pages that are custom sent to each airline and https://www.youtube.com/channel/UCJiw_egCKvL8Jnrxl... was on both management and fellow pilots to get them to pay attention to the problem. He says he quit the airline in frustration that they were going to get someone killed a month or so before the crash.

The Ethiopian CAA, the Ethiopian Airlines management, and the Ethiopian Chief Pilot did nothing, even though they were all aware of the likelihood of fatality if the crews were off even a little bit. Instead of grounding their own fleet until Boeing certified a fix, they decided to just not know. So far their plan to try to blame Boeing is working. Notice that none of those three levels of the company are named in their preliminary report.

The Ethiopian pilots were handed on a silver platter two ways to handle the situation, complete with symptoms, and the AD and the FCOM and a pilot begging them to pay attention and they did every single thing the AD said not to do.

The reason for the last enabling of the trim, the one that let MCAS have a last shot? To try the autopilot one more time, as evidenced by the AP fail alarm, which only happens when someone tries to enable the AP when the AP cannot function. They know that the AP cannot be enabled with a stall warning; at least that is how they are supposed to be trained. They tried at least 3 times; first item is to disable AP, then disable AT. They never disabled the AT. And they were told to never re-enable the trim after having selected it off.

So where in the preliminary report do they discuss the frequent review sessions, the special simulator training for just this failure, the extensive testing and scrutiny from the Ethiopian CAA, the Ethiopian Airlines management, the memos and responses and personal oversight of the Chief Pilot? How about their respective decisions to proceed after doing exactly nothing?

All pilots agree that Boeing lied completely about every thing forever about MCAS and the FAA covered it up. So why did Ethiopian proceed on the belief that Boeing and the FAA were telling the entire truth when they did not describe the steps as one might tell a 5 year old locked alone in the cockpit for the first time?

We know from the successful flight that it's a matter that humans can intervene with successful results. It takes what should be the bottom-of-the class skill to trim the plane with a thumb and the ability for 1 of 2 pilots to recall the trim cutout. That, tragically, is it.

The main bulk of the interim report is second guessing every engineering step. Interesting as it is, almost nothing of it has to do with putting that plane into the ground on that day based on what was known to the operator months before. The lack of introspection required to keep the lawyers from blowing Ethiopian Airlines, the nationalized airline, to smithereens by a report by the same government as owns and operates the airline is appalling.

(edits for typos. damn typos.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Yes, and they tried to trim manually, just like they were supposed to.
The old Boeing knew that that may not be possible, but the new Boeing culture falsely assured them of the possibility of manually trimming when the stabilizer was at an extreme pitch.
Manual with the trim wheels, not the switches.
In retrospect, a simple instruction to not leave the Stab Trim switches on for more than 4 seconds after a trim event would have saved a lot of lives.
As for the super trained and experienced American pilots being able to easily handle a MAC ATTACK, That was well and truly blown out the window when they did the series of simulator tests with mostly American super pilots.
By then everyone knew of the issues and the pilots should have been expecting an MCAS malfunction.
Most of the pilots did not follow procedures properly.
I understand that a couple of super pilots screwed up so badly that the simulator needed repairs when they finished their session.
Boeing said that the pilots didn't need more training.
Boeing downplayed more training.
Boeing opposed an airline who wanted a Max 8 simulator.
Boeing has messed up so royally, so many different ways, that the blame the pilots card won't play anymore.
I think that Boeing's latest leader has blown his credibility out of the air with his renewed attempt play the American Super Pilot versus Third World Pilots card after the sim tests.
First world pilots may be and probably are better able to handle an emergency, but proven in the sim, are not good enough to handle a MAC Attack.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I wouldn't put to much value in the ET report, as I said before it stinks and agree with Dave over the bum covering by ET and the authorities. It won't wash though globally. I hope its a copy and paste job to satisfy the requirement to publish something inside 1 year.

To be honest though the other issues with the MAX have overtaken the initial accidents. There is no way they can roll back the clock and unground the MAX even if the ET is deemed to be 100% airline and pilot fault. Its been proven now that it should never have been certified in the first place. And the fundamental risk analysis for a multitude of systems was false.

Its looking pretty certain now that a 3rd AoA sensor will be required on all new types what ever the grandfather rights are. Which will pretty much blow out all grandfather cockpits.

And this corona virus is likely to take out an extremely large number of the orders anyway. Airbus is in the same predicament.

I am grounded until at least the 17th of April. The borders are shut to none citizens/resident holders. And commercial air transport has been banned by the government.

Within the next 2 months I expect at least a 25% reduction in operating Airlines in the world. Its going to take years for things to normalise in aviation. By the time this runs its course I suspect Boeing and Airbus will have substantially reduced order books. And its going to be an extremely slow 5-6 years before things pick up again.

I suspect the USA will be in the same state in 2-3 weeks with basically all commercial air transport grounded for a month plus.

We shall see, I have been on vacation for most of this month so am away from it all. But got the phone call "where are you?" "ok good stay there" at least I have something to do building my holiday house. But once the materials I have already bought run out then it will be into save money mode.

Thankfully the locals don't seem to be as stupid as my nationality country, there is still toilet rolls etc in the supermarkets.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

That's bog rolls, to you! wink

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

In the US, we have normal people and then a few that if bog rolls were money, they would be billionaires. A bidet is looking more useful every day now.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

"Ask the audience" usually results in the correct answer; binge buying reduces the number of trips to the store at a later date, when the virus is running amuck, while it's still a relatively safe gamble right now.

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: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Just put a bidet sprayer in both toilets.

The Mrs is quiet happy telling everyone it's a fanny washer in English. I will leave it for a bit until I tell her that fanny in Scotland is not the same as fanny in America.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (AH)

The Mrs is quiet happy telling everyone it's a fanny washer in English. I will leave it for a bit until I tell her that fanny in Scotland is not the same as fanny in America.
rofl Stop it, you're killing me!

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Well I suspect USA not that far behind Europe now. They shut midway airport due to 3 technicians testing positive.

And a mate who was in Daytona last week is now at home feeling sorry for himself with it in the UK. Knowing him that will be half the strip clubs in Daytona and Miami contaminated.

Anyway last year I ordered 2 workshop blue elephant bog rolls and 2 bales of 8 were delivered with a 15ltr tub of lemon Swarfega so that's the hand cleaner/shower gel sorted as well. So maybe Jan 2021, I would need to start the second roll. Although I suspect I would end up with a baboon's bum after a week.




RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I know some Boeing peeps will be reading this, my heart felt feelings to loosing a colleague. Its too late now and you will have more.. Its a bitch this virus thing....

Anyway a bit of humour with a slight engineering disaster bent...

I like copper pipe I don't like plastic...

I did my place up with it and bonded everything to 4 huge earth spikes. Plastic into the basement after that copper and bonded to old school regs including the kitchen sink with a 6mm2 bit of wire to the main earth.

Brother in law due to my copper bent has done his shower room plumbing using copper pipe. The supply to the hot water and inlet cold is plastic.... No bonding....

Said "fanny washer" is now a thing with the local lady's. They all want one... I gave a spare to the BIL.

It was put on line today...

The screams when the fanny washer earthed through the toilet were unbelievable after 20m of copper pipe building up static.... 3 bar...

my ribs are hurting with laughing...

I have 20m of 6mm2 wire in stock and earthing bands so will sort it tomorrow, but I had tears in my eyes tonight after we worked out what the screaming was about.

Apparently singing various lines out of rock horror show is not funny....

I am a Mechie what do I know about electrical stuff?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I had a call to a diving resort.
A guest was brushing his teeth and got a nasty shock when he tried to get a drink directly from the faucet.
I put my meter on it and zero volts.
Continuity test.
Well grounded.
I put my meter between the faucet and the floor where the victim would have been standing and read 60 Volts.
Down under the cabin and found a cable stapled on edge with a fence staple.
The staple had been over driven, pushed through the plastic insulation and contacted the hot wire.
Measuring the floor joist to ground a couple of inches away from the staple I saw over 100 Volts.
North America is a continent.
South America is a continent.
Central America is not a continent.
Must be incontinent.
The joys of working in the turd world.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

See that as a mechie is just alien. I stick my ground spikes in and over bond everything to death....

stick loads of RCB's in and just deal with them kicking out when a neutral touches an earth when you doing stuff.

I really don't have a clue what I am doing apart from rule of thumbs and common sense of check every thing before I touch it.

Although getting a belt through your mouth V getting one through your reproductive organs I will not entertain the pro's/cons of.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

AH, it sounds like BIL unwittingly prepared an inductive spark system experiment with the gap localized to the, ahem, fanny washer shocked

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Thinking about what Bill said... there is electric UFH DIY installed and the RE bar wasn't bonded he say's....


Anyway back to the MAX.. Moss lake shutdown for maint on Max's and Puget Sound factory shut down for production.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

With all the shutdowns due to SARS-CoV-2 any hope Boeing had of maintaining schedule is definitely shot. Suppliers will be shut down as non-essential. The US airline industry is collapsing (and begging for bailouts), tourism is down worldwide, so a lot more orders will be cancelled. Regulators have no reason to hurry, and many won't even be able to send people to inspect things due to lockdowns.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Could this virus kill the 737 max?

Airlines are going to be dropping like flies and could take 5+ years to recover.

I suspect there will be a lot of spare cheap aircraft around and I see nothing but cancelled orders.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I doubt the suppliers will be shutdown (although they may choose to on there own). Based on my states listing of essential business nearly everybody qualifies including tobacco manufacturers. Look for yourself Essential Businesses

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Boeing was mentioned repeatedly in yesterday's (or the day before, they are running together) COVID presser as it pertained to the stimulus package. Boeing was called out as a very big part of our economy and have fallen under some tough times lately so it is important that they get bailed out. Just when it looked like MCAS was going to auger them they've found some parachutes after all.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Too big to fail? Does that really mean too well connected to fail?
If COVID 19 leads to greatly reduced passengers world wide and failing airlines, there should be a lot of openings on the Airbus waiting list.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Boeing should pull itself up with it's bootstraps like the American populace will have to.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (USA Today)

BOSTON – A gas company accepted responsibility Wednesday for a deadly series of natural gas explosions that rocked Massachusetts in September 2018, agreeing to pay a $53 million fine and end its operations in the state in a plea deal reached with the U.S. Justice Department.

Columbia Gas Co. of Massachusetts (CMA) will plead guilty to felony charges for not meeting safety standards that led to the catastrophic explosions. U.S. Attorney Andrew Lelling said the criminal fine is "by far" the largest under the 1960s-era federal Pipeline Safety Act.

The parent company of CMA, Indiana-based NiSource Inc., also must sell its subsidiary, stop doing business in Massachusetts and pay the U.S. government any profits made from the company's sale. Until it is sold, a third-party monitor will regularly inspect CMA, which will be on a three-year probation. As part of the deal, prosecutors will not pursue charges against NiSource for the conduct of CMA.
There was one death.

Extrapolating that for Boeing would be a little over 18 billion in fines.
New owners? That may be what it takes to change the company culture.
Any profit for the sale to be forfeit to the government. Better than going to jail.

Will it happen?
Well that's the difference between big and little in "equal" America.
What ever happened to the concept of "Common Law".

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Give it 4 weeks and see what happens.

The virus is firmly established in all politician groups in Europe. They have been dropping like flies with it.
There was multiple visits by EASA before the European lockdowns.

I suspect the Boeing shutdown was a tad too late and with all the meetings that will be involved getting the MAX flying again there will be a sudden onset of people dropping out for 2-3 weeks getting over the virus.

By people on my FB with it its not something you can battle on with. Your pretty much totalled for 5-6 days with headache and fever and then the coughing lasts a lot longer. Thankfully nobody as yet has needed to go to hospital. The ones that have it are separate to each other. They all can pin point where they got it. Funerals, meetings, and ski trips.

With the amount of international meetings involved with the Max I would be very surprised if Boeing doesn't know its got a major issue looming anyway. The FAA will have it as well.

And all the lobbying that Boeing does its almost a perfect vector for injecting it into pretty much every corner of the aviation establishment in the USA.

The news in Europe is focusing on the likely hood of the USA opening up for business again soon. There are several by lines noting the ages of the political leadership of the various offices in the US. Which a rather large percentage is in the 8% fatality zone. With a substantial number being in the 15% zone.

So give it 4 weeks the picture might have changed significantly. The MAX will fly again at some point. I pretty sure though now it won't be until 2021.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Small update

2 more issues with software have come up with the MAX.

1 is to do with the cosmic radiation causing pitch inputs again both up and down. Which is a pie ion the sky test and very unlikely to happen in real life

And the second one is the autopilot getting kicked out during low vis approaches while doing CAT II and III. Due to the FC's loosing sync and the fail safe is dump the AP.

Test flights unsurprisingly are not going to happen for a couple of months so plenty of time to deal with the new issues.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Maybe it's time to take another look at the email from Canada's regulator which stated that MCAS had to go.
When it was thought that a few lines of code and a few weeks would get the plane flying, the odds were dramatically against repositioning the engines.
Now, in hindsight, with the amount of money spent and lost, the amount of time spent and lost, and the amount of reputation and public trust lost, the odds have shifted dramatically.
Yes, the wings may have to be redesigned. Doesn't Boeing do that sort of thing? (overlooking the pickle fork issues)
Wasn't that done in any event to handle the increased forces of the repositioned engines? I hope so.
Yes, the landing gear may have to be redesigned. Doesn't Boeing do that sort of thing? Didn't they do it for the Max 10?
Is Boeing still able to design planes or have the best engineers left the Boeing culture and found rewarding work elsewhere?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There has been that many additional issues come up in the mean time that MCAS is more than likely on the easier end of the scale to deal with now.

Shifting the engines isn't going to solve the wiring issues, the cockpit alerting system and checklists, the inability to manually trim the plane outside a small speed window from neutral trim etc etc etc


There is loads of other issues that are now stopping the recertification. The thing should never have been in the air in the first place.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Alistair Heaton)

The thing should never have been in the air in the first place.

Maybe not but you can see how there was nothing really big enough to stop it (Once they managed to convince themselves that the MCAS failure wasn't "catastrophic"). Unfortunately for Boeing that analysis has proved to be false . Everything else could be magicked away by the grandfather rules and the excuse - well the 737NG doesn't fall out of the sky on a regular basis - would have been well worn.

But once something happens like this, you need to sort out all the other issues which arise as that excuse just won't wash anymore.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There is stuff turning up like the wiring looms which was completely outside certification standards and couldn't be grandfathered through.

And your right there was nothing to stop it after they managed to blindside the FAA into certifying it until it killed so many people.

But now its getting certified properly by multiple regulators because the FAA screwed it up.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I think that's going to be a much bigger issue... everyone will be looking at it with a fine toothed comb. Also FAA reputation has taken a big hit with agencies that matter. The FAA may never recover their original reputation.

Dik

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Sorting out the regulators will only occur after the MAX is flying again.

And while its happening there will be several changes to the cockpit alerting system setup as well. Zero grandfathering ability's allowed like the wiring loom reg.

But to be fair to Boeing they seem to be declaring issues instead of them being found. I suspect this is due to the fact they know that the flight envelope is in an extremely perilous situation of being outside regulations which the MCAS was installed to fix. We shall see what happens.

Boeing have a ridiculous amount of work in progress.

The space side of things they are doing another unmanned test flight.

And the mil tanker contract is just a mess. They have just had to start completely re designing the boom control system. And face the US military having to lease in the oppositions product to cover the gap and back charging them. Which will more than likely cost the same as the original contract which they got cancelled.

And all this while trying to keep everyone virus free.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

If Boeing gets the $17 billion USD "loan" as a coronavirus bailout, it will set a precedent and will effectively mean that they are "too big to fail" . Certainly one can justify that national security requires their military arm be subsidized, but in reality the "loan" is bailing out their missteps in the 737 Max commercial debacle. They are then effectively vaccinated against future financial failure as they can always play the same "get out of jail free" card by crying "national security". This will likely be seen as a transparent government support to a commercial entity and thus disqualify them from bidding in the european market. This might explain why they have not chosen to split into 2 divisions ( military vs commercial) , as that split would void their ability to play the same national security card after the next debacle occurs.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (USA Today April 3)

Why Boeing might not need a bailout despite coronavirus, 737 Max crises
.....
Boeing isn’t mentioned by name in the 880-page bill. But the aerospace giant will qualify for as much as $17 billion in taxpayer relief through this language threaded into the fourth paragraph of page 513 of the CARES Act: “businesses critical to maintaining the national security.”
.....
After recently drawing a $13.8 billion bank loan, Boeing has about $24 billion in cash on hand, according to Debtwire estimates.
Link

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I think one of the conditions of getting Government money is that the government take some % of ownership.

And there is no way Boeing board will want that and limit there ability to issues shares etc to board members.

And as for splitting well that's all very good if you have a cancerous limb. As far as I can see all the main sectors that Boeing is heavily involved in they have screwed up and have huge liabilities. So they need more of a chemotherapy treatment than an amputation.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Boeing will work their way out of this with good old American ingenuity.
About 40 Billions worth.
They have just secured a bank loan for 13.8 billions.

Quote (USAToday)

After recently drawing a $13.8 billion bank loan, Boeing has about $24 billion in cash on hand, according to Debtwire estimates.
By the way, as far as I know, Boeing has not yet accepted any government money.
Despite that, one board member has resigned over the issue.

Quote (USAToday)

Critics of a bailout include former United States Ambassador to the United Nations and former South Carolina Gov. Nikki Haley, who resigned from Boeing's board in protest.
The bailout figure is 17 billions.
With the cash on hand, another 17 billion would but Boeing's available cash at over 40 billions.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Is that enough to buy back all the maxes and then rebuild them / strip them for a newly designed aircraft?

Now the market for aircraft is going to tank in the next 5 years stranger things have happened.

Someone somewhere in Boeing will be running the numbers....

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Biggest problem with that idea would be the production would be shut down for 5 years. They would find it next to impossible to get going again in any sort of volume. Most of the suppliers would have gone off to do something else or got rid of the workforce.

The MAX will fly again in its current Frankenstein state with modifications.

I don't think they will be stupid enough to entertain another iteration in the 737 family though.

They have that many areas that they need to develop products in.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]


A certification flight required to clear the grounding on the 737 MAX is awaiting software validation, with Boeing CEO Dave Calhoun anticipating a third quarter return to service, according to the company’s Apr. 29 first quarter earnings call.

The certification flight awaits software validation for the 737 MAX flight control computer (FCC). Calhoun gave no timeline on when the software validation effort would be complete.
Link

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

2
(OP)
Although not a step in Boeing's journey to restoring faith in their aircraft, nor toward certification of the 737, this is a very interesting event.
It is an asset to the Seattle Times and will mark Boeing for a very long time:

For groundbreaking stories that exposed design flaws in the Boeing 737 MAX that led to two deadly crashes and revealed failures in government oversight.
https://www.pulitzer.org/winners/dominic-gates-ste...

My sincere congratulations, esp. to Dominic Gates, whose articles I've come to rely on to understand many aviation issues (not just the 737 ones). medal

www.sparweb.ca

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I will say as well that Seattle Times has been my go to first media outlet for aviation content for over a year now. To be honest mixing in with links from PhD mates about the virus stuff it seems to be more informed about that subject as well.

I if Dominic Gates picks this up I salute you Sir as a pilot and ex engineer. You are reporting in a truthful educated manner.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Hope you guys are paying for your access, though I cannot blame you if you don't (I don't pay for articles online very often either). I have been a subscriber to the ST for 20+ years, as it's my "local" paper. They have been pretty reliable reporters over the decades, on a variety of subjects. One of those subjects is the fairly rapid decline in local newspapers (and local reporters) due to buyouts from conglomerate enterprises, resulting in a lot of stories going un-reported or at least under-investigated.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Sorry but I don't, mainly due to its extremely hard internationally to pay for a subscription. The ST should actually think about making it easier. I am not alone being a none USA pilot using them for a primary source of info about Boeing.

BTW on the subjects of Aviation and IT I would consider it international.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

This might be of interest to some.

The c series/A220 AoA setup.

It uses as the primary AoA static ports on the Pitot tubes to calculate AoA. It uses traditional AoA vanes as the standby/back up.

They are grouped in three's, So two static port sensors and 1 vane, there is comparison checks between the three in a group. The two groups are then compared for mismatch.

You have the ability to going into reversion swapping between groups and feeding one sensor to both groups.

So in total you have 6 AoA sensors. Error checking between 3 of them and then mismatch checking between the two groups. There are 3 independent flight control computers doing the checking, and they also do a sanity check referring to the IRS and Airdata computers if everything is inside a plausible envelope. If its not then the flight law changes and the pilot has to sort it out.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Are the AoA sensors counterbalanced, or do they drop down when the aircraft is stationery?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The main ones are not vanes. They have 2 static ports on the side of the pitot tubes. And the box of tricks works out the AoA from them.

The standby/backup vanes I really don't know what they do on the ground will take a look next time I am near one.

This pic seems to indicate they stay put.



The front line of 3 probes are top two pitot tubes and bottom one is a true air temperature sensor. the one under the window is the vane.. which looks straight to me.

here is a link to the pitot AoA system

http://www.goodrich.com/cap/systems/sisdocuments/A...

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Thanks.
I was thinking; If the counterweight was trimmed so the vane pivoted down when at rest, They could have a three point check each takeoff.
1. At rest. Known check position vertical.
2. Takeoff run. Known check position horizontal.
3.Takeoff run. Transition from vertical to horizontal at known speed, freedom of movement, binding.
It looks as if the vane is 100% balanced by the counterweight so that idea goes out the window.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I recall looking into this earlier, and there is definitely a counterweight involved. The issue has never been the counterweight, per se; that's all processed internally, but the AoA sensor outputs will still give stupid answers, even on the ground, without the flight computer issuing a critical failure warning.

If you go back to the earlier parts of this specific thread, the FDRs show that the one, and only, AoA sensor being used for the stall indication was giving erroneous values even during taxiing, which one would think, should have caused an alert to the pilots to abort the the takeoff, since the AoA is such a critical part of the flight controls.

This shows that the whole issue isn't simply just the AoA sensor itself, but a failure to adequately detect anomalies in the sensor data, even on the ground, prior to takeoff. That is a serious problem that is hopefully resolved, but I'm a bit skeptical.

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: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I'm thinking, optical limit switches at the vertical and horizontal positions.
An independent circuit that takes inputs from both the limit switches and from the AoA indication from the flight computer.
That could prove the entire AoA system not just the mechanical function of the AoA vanes.


Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The local winds around the aircraft operated at low speeds, such as during taxiing, mean no meaningful information is gained from AoA sensors. There will be no stall warning with weight on wheels.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The problem was that the AoA was malfunctioning on the ground; that's a BIT problem which the flight computer should have been able to resolve and warn the pilots to abort takeoff

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Thanks Dave.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The AoA sensor on the Lion Air plane was malfunctioning in the maintenance hanger, but maintenance workers did not perform any post maintenance check to see if they had done the work correctly. Subsequently, with the benefit of hindsight, it was clear there was a difference in readings during takeoff, at which point it was too late.

On-ground conditions are not suitable during taxi to diagnose a problem. There is no BIT that can detect it without also giving an unacceptable number of false positives. Full hard braking of a fully fueled and loaded jet liner has a non-zero chance to end in a run-off fireball crash.

The "fix" would see pilots on step ladders moving the vanes manually with a precision level attached or some vernier marking; of course if the Lion Air repair team had bothered to do that most of this conversation would not be happening.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There is usually a scale on the metal next to the vane with a pointer which is crude. But would have picked up the colossal discrepancy that the lion air had. But you would have had to have access to the AoA reading in the cockpit which was a 200k software upgrade per aircraft which only one customer paid for. Everyone is now getting it for free. I don't have a clue if the AoA mismatch flag which wasn't working would have saved the day. I suspect not because it would have only been activated when the WOW indicated airborne. There is zero possibility to get pilots checking calibration pre flight that is a technician function. 15 years ago I did hold several maint approvals for doing checks and even changing tyres but 10 years ago the regulators banded it. We have 4 pilots that were licensed B1's and even they are not allowed to fix the plane if anything goes wrong in a outstation. They can do more than the rest of us with written instruction from the CAMO but its extremely limited and seldom used. Everytime they fix something a report is sent to the CAA. If they do work in the hanger then a report also needs to be filled out and proof that the working time has been added to the FTL records shown.

There is three bite tests and checks of the sensors that I can see so far for the A220 before the wheels leave the ground from power on. If the power stays on for the day its 3 on the first flight and then one per flight.

The first is on power up which are for things speaking to each other and general is it working.

Second is after the IRS come online which can take 20 mins after power up depending how far north/south you are. We don't need to know what's happening thankfully the EICAS will tell us what's wrong and if something is showing red we phone the technicians.

Third is at 60 knots every takeoff. And it will tell you to abort the departure. If something is a go item it won't tell you about the failure until 400ft. If you need to stop it will set the bells and whistles master caution system off and you abort. There is no interpretation required or thinking. If alarms go off you hit the brakes the plane takes the power off if you haven't already. If you pull the power levers back it automatically triggers the autobrakes for emergency deceleration. There is something about variable breaking power depending on the speed you abort at and the runway left but I haven't done brakes yet.

I wouldn't disagree with the statement that full hard braking won't result in a runway excursion. A lot of runways in the 1st world have deceleration pits at the ends to increase the effective runway available for takeoff. But they aren't strong enough to taxi on. If you go in them the plane sinks. Its a fudge to allow higher weights for departure but not have to pay for runway that never gets a tyre on it 99.99% of the time. They are though extremely effective when used. Not much damage to the aircraft just a bit of gravel rash and a gear inspection and it will be flying again usually the same day.

There are basically two aborts. Low energy under 80knts which you stop for anything caution or warning.

Second is high energy abort between 80knts and V1. The performance is calculated that you will remain on the ASDA (accelerated stop distance available) but there may be damage to the aircraft tyres blown, fire service needing to deal with brake fires and the aircraft requiring maint inspection. Just before V1 abort on a +100 ton aircraft is pretty major to be honest. And can damage the runway. You only stop for certain failures.

Between V1 and Vr you don't have enough ASDA in front of you to stop, but you do have enough to accelerate with an engine failed and take off before the end. Which may mean that the wheels only leave the ground on the piano keys at the end of the runway. Things are further complicated with the use of de rated departures and flex where the engine power is set for the runway length and conditions.

This rejection stuff comes up every day we are in the sim. There is at least 1 go situation and 1 abort situation. And its pretty horrible on a none EICAS machine. You have the attention getting going off then is it a yellow or red then PM should call it. You should remember what the last speed call was. Then decide if to go or not. All while 9000 shaft horse power is throwing a 22k to 29.5k kg aircraft down the runway in the case of a Q400. At 22k kg we are off the ground at 130 mph inside 10 seconds. Quite looking forward to this not having to think stuff with the EICAS.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There are noises that Boeing will be doing a FAA recertification flights before the end of June.

There is nothing from EASA or the other regulators. With the quarantine rules they would be all hit with two weeks coming back.

So if they approve it you might see a 737 max in the air by October with pax on it on USA internal flights if the FAA release it. They still have to do the training side of things.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

This is for interest. I didn't see the point of giving it a thread to itself. Its a 737-800 but it could happen to any type. Just thought it was a nice report and for once the pilots didn't screw up.

FOD is always a worry but not a lot you can do about it.

The departure airport is always one that causes increased thought. Not quiet as bad as Varga but still your surrounded by water and lengthy transits if you don't want to go straight back.

Lovely place to operate into when the weather is nice when its orrible which is most of the time its requires you to be very switched on while feet wet.

http://www.rnsa.is/media/4688/final-report-ei-fhd-...

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The report makes it sound almost leisurely; seems like they had ample time to do all the right things. Had the FOD damage been worse, the outcome could have been very different.

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RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Detailed inspection of the aircraft revealed the following damage:
 LH inboard main wheel tire burst
 Four (4) broken spoiler cables
 Downlock sensor system wire cut
 Air-ground sensor system wire cut
 Fuel temperature system wire cut
 Two (2) landing retract/extract hydraulic line broken
 Four (4) tubes to heat exchanger broken
 Three (3) tubes for brake/shimmy damper broken
 One (1) tube for engine driven pump pressure supply dented
 One (1) tube from shut off valve broken
 Flow regulator valve missing from LH wheel well for hydraulic system A
 Aileron pulley broken in wheel well
 Three (3) spoiler pulleys broken
 Fixed trailing edge panel punctured
 Support brackets for hydraulic pipes including fairleads damaged
 Dents on both main and aft inboard flaps
 Dent on LH horizontal stabilize


That's quiet a hefty damage bill to be honest And also one of the primary hydraulics circuits gone. Turn spoilers/lift dump gone. Alternate gear extension pretty horrible day at work in central Europe never mind hundreds of miles of hostile ocean to go over or return to a very short runway.
I was wondering why they didn't go for Prestwick but then if you have managed to get from Iceland to UK without any issues an extra 15 -20 mins in the cruise to go to BHX doesn't make any difference compared to going to Prestwick without any company tech support.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The report indicates the crew considered and rejected Prestwick in favor of Birmingham, presumably for both better ground support and a longer runway. Prestwick's runway was just shy of their desired 3-km length, while Birmingham is at 3.66 km

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RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

If you where going for length and safety you would go for Manchester with twin 3km runways 3048 and 3050

BHX is 3052 meters single runway.

PIK is 2986m

Campbell town also used have a 3km runway which was a space shuttle diversion airport along with PIK.

Plausible excuse that nobody cares about would be what i would term it.

I do know someone that went past MAN and BHX and landed in Stansted after an engine failure. When asked why he went there he answer that's where my car is parked the bird is 180 mins ETOPs certified and we had only had the engine shut down for 20 mins, another 20 mins to get to my car shouldn't be a problem... The AIBB bloke just smiled and said right I don't think we will bother discussing that point in the report.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

They traded also the possibility of tying a busy runway if the plane became disabled or seriously damaged on landing, so I expect that might have played into not picking Manchester

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RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I am maybe a bit biased about going anywhere near BHX due to having worked in there for 2 years. Both ends of the runway can give sporty conditions in even moderate winds. Plus the runway is not exactly flat.

This video is doing the rounds of pilots just now.

Totally mucked up the de-crabbing and flare and put full wrong direction alerions deflection in after touch down. Plus they look as if they slammed it into beta range. There wont be a report on this one though.

https://youtu.be/H5mnCEMzV-0

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Like I said, leisurely, so they had time to get weather reports, etc., to flesh out their decision. Then, again, maybe they thought it fitting that if they were to disable a runway, that it be BHX's

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RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

which is another reason to go to MAN they have two fire stations one for each runway and can continue operations with one team at an incident and one runway down up to 747 or A380 size inbounds.

The first decision not to go back would have been done relatively quickly before high level climb. The rest they had plenty of time to do.

It will centre round maint bases and where there is a spare aircraft for the punters. BHX is actually very busy with plenty of heavy hardware in and out, about the same as Manchester.

They used to have quiet a few planes going through there but closed it in 2017.

You normally you try not to go to crash at your own company's operations. You go somewhere else. Liverpool was getting well pissed off with a previous company of mine because we always went there if there was any problems going to MAN,BHX or LBA. There was a good hanger there to fix things as well. And the bus ride wasn't that long to get the pax to destination. So there runway was shut multiple times for hours with usually hydraulic issues and then needed towed off and the runway inspected and fixed if a tyre had blown.


As I said plausible excuse that nobody cares about.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (AH)

I do know someone that went past MAN and BHX and landed in Stansted after an engine failure. When asked why he went there he answer that's where my car is parked
That reminds me of some trips from Vancouver to the Okanagan valley many years ago.
The flight was to Penticton and Kelowna. (A Kelowna ticket was $0.50 more due to an airport tax.)
Whichever city the flight landed at, passengers would be bused to the other city.
When the flight left Vancouver the pilots did not know their destination.
When they got within radio range of Penticton and Kelowna they would ask ATC;
"Where is the bus parked today?"
They would then divert either North or South and land at the city where the bus was, and announce to the passengers what the destination would be. This was about 15 or 20 minutes before touch-down.
I lived between the two cities.
Once I learned the system I always bought a ticket to Penticton and saved the $0.50.
There was no check of ticket destination.
I would get on the bus with my carry-on and the driver would let me off as we passed within walking distance of home.

"When asked why he went there he answer that's where my car is parked"
"Where is the bus parked today?"

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I had a quick look on GE.

Birmingham tarmac is 3000m, but piano keys to keys is only 2300 whets stn or PIK is 2759. Runway is 15/33 which is quite strange for the UK where many are much more east west so maybe that was included in their assessment. Definitely more room to run off the end a bit.

It's still rather frightening that the wheel bays were so vulnerable though. Punctured tyres aren't that rare. And all from a piece of metal as long as your hand.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It was FOD that got Concorde in the end. The BA ones had a tyre stripper on the wheels but AF never fitted it. There was multiple other issues with that flight but the tyre getting taken out was the start of the other issues being able to come to the fore.

Piano keys to piano doesn't really give the full picture there are multiple rules about what you can and can't use as your distances for landing and take-off and they can be significantly different depending on the objects off either end of the runway. Touch down marker to end of the runway is a good enough approximation.

But I would be surprised if PIK is worse off than BHX. Most of PIK's life it has been a NATO heavy Nuke bomber designated runway. It is utterly colossal and there is nothing much round it only thing that will beat it are the eastern Germany runways but they are all concrete slab. Its also one of these microclimate airports where the local wx system is usually much better than the rest of the UK. BHX is a pain in the the bum sporty approach slippery in the last third up and down wavy runway, As the ATP tried to do you have to try and hit the top of the first hill other wise you end up floating down the back side. Anyway Just because I would think twice about taking a sick aircraft their is only my personal opinion and mostly dictated by having over 1000 landings there. I have similar at MAN and apart from the pissing rain it would be my preferred option.

Tyres are never really give the respect they are due to be honest in my experience. Each one is a bomb sitting on your aircraft. They are fitted with thermal fuses and the like but they are expected to sit in sub zero temps for hours then get smashed into the deck and spun up to 110-150 knts in fractions of a second then have to transfer colossal amounts of energy through them. IF they let go there is colossal energy stored in them. I tend to not go near them after landing and when I have to approach them do so in the alleged safe zone.

And a complete explosion of a tyre like that is relatively rare thankfully, I have never had one. And only one mate has had something even remotely similar. It was the youtube video of the Q400 tyre deflating on takeoff in AMS and they eventually landed back in the UK i think. Thankfully that was a none event apart from the media hype.

Honestly I wouldn't get to into why they went to BHX, they will have been discussing it with ops and they will have given them a preferred airport to get to. That will have included the availability of another crew and aircraft to move the pax onwards, engineering support, ground handling, departure slots available (which is a pain in the bum at MAN at peak times). If the aircraft has been running ok for the previous 2 hours feet wet with both engines still working and you have multiple options in front of you/around you its really not a big deal. Personally I would have preferred PIK, Man or East Midlands at 2893 meters but thats just me based on personal experience of all the UK airports flying regional turboprop which this crew more than likely didn't have. I would be in the same situation in there native countries.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Just been reading about the FAA stuff must admit I don't understand or know about the USA legal process with this. From what I can see is there is a major push from both sides to either maintain current situation with the FAA and Boeing or dial back the clock 30 years.

To be honest I can't see much difference between the current investigations and the Challenger post accident process and NASA. A lot of people move jobs or retire and fade out of the picture, there is noise and people are a bit more cautious for a period and then a new genration come along who have vague memory's of the period and then it goes back to the way it was.

Only thing different is the international aspect to to this because although big the USA market is only a part of the bigger sales picture. So if the USA doesn't fix it properly the planes won't be getting a world wide certification and they will have to do it properly anyway, which will mean the aircraft will be built differently anyway. We shall see what happens in that regard i can't see things going back to multi national certification of new types until there has been 2-3 new aircraft go through the system which will occur for the 737 MAX to get it flying again with no problems. And as Boeing doesn't have anything even remotely on the books for future development that will take some time.

Must admit hearing some of the political types spout off you do wonder if they realise that it doesn't matter what the home grown voters think when it comes to the FAA if the rest of the world doesn't buy it, then Boeing is going to have to walk the walk anyway or its a dead duck.

The issue of grandfather rights and design auditing for human factors though is an international issue and needs to be applied globally. And more than a few pilots think its about time the airbus FBW system is revisited on the human factors front, and i am one of them. The PIA thread on this forum is case in point for the reasons why.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

BHX looks like an interesting runway alright....

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

^I asked my dad about that in the 70's, and he said they'd looked at that in the 40's. Nothing that would justify the weight penalty, maybe that'll changed someday.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

They are also talking about putting drive wheels on the nose gear so the engines are not running going out to the runway. I can't see it happening due to weight penalties either.

Aye BHX is a bit of swine if you don't touch down ontop of that first bump. You have to increase the rate of decent due to ground falling away. Then it comes back up and hits you. They have built up stuff round the airport and wind coming from certain directions turns the approach into a bit of a washing machine in the last 500ft.

You can't see it in the photo but they have lots of rubber in the touch down zone, it is a grooved runway and when its been cleaned of rubber which I think they do by burning it off its pretty good. Just before cleaning though its very slippery when even damp.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Up date on progress and which systems the regulators are having issues with.

https://www.seattletimes.com/business/boeing-aeros...

All has seemed to have go quiet about wiring looms and control run routings.

I don't known though if there is any demand for new aircraft or for that matter if the public will be happy to fly on them until everything is fixed. Take delivery of an airframe which you know will require major mods in the near future and nobody is flying anyway so demand is extremely low.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It appears that Boeing and the FAA will start conducting a series of test flights of the 737-MAX8 aircraft as early as this Monday. This will involve an aircraft, loaded with instruments, which will conduct various simulated scenarios testing the systems and subsystem which the experts believe were responsible for the crashes that grounded the 737-MAX more than a year ago:

Boeing set for critical 737 Max flight tests

https://www.bbc.com/news/business-53212274

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

You can usually follow them on most flight trackers.

They fly under BOE

So on Monday have a look for BOE1. They usually take off about 12:00 GMT

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Let's hope that "Software Defined Aircraft" don't have 'systems crashes".

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Seems they are using BOE701

They do sometimes have system crashes. But the backup systems spots it and removes the offending computer from having any input to the flight. The aircraft then down grades things then takes the offending computer down. Brings it back up and then you have everything back to normal again. If it then fails x number of times in a row it then it throws other cautions up which then you can then sort by say taking a sensor out of the equation and reverting. Then everything works again. Well that's the way it works on a proper FBW machine. Quite what this 1960's Frankenstein contraption will do I really don't know.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

That Frankenstein contraption is better put together than the CAAs of at least 3 countries we know of.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

System Engineering, if performed competently, should feature robustness and resilience in the event of single point failures, and should at all times make maximum use of remaining reliable components to minimize the effect of one or more component failures.
That may be a big if.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It's a tough row to hoe from systems engineering principles to actual practice. But, SE, per se, is usually not the onlt problem, it's also a number of other problems
> shiny new SEs that know SE principles, but not how or why a system exists
> requirements creep because the requirements have to be iterated multiple times because of "I forgots"
> poor management because the managers don't know what's going on
> ballooning costs
> poor systems engineering on the legacy portion of the system

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RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I would say there is a lot more CAA's than that Dave. And to be honest its the regulation that just as much at fault here than anything else.

I must admit I am just about finished learning a new fresh sheet type. Don't get me wrong there is a bug list as long as your arm even though its been in there air for 3 years now. And there is a well defined method of submitting bugs and regular updates to clear them. But compared to the Q400 which was a 4 generation upgrade stretch its absolutely heaven. There is crap on that beast that will never be fixed because its just the way the system has to be because of the changes. All the issues which I am seeing are all icing on the cake getting things working which were planned to be working. So its all stuff which is envisaged should work 99.99999% of the time but it only working 99.9 of the time and they are fixing it. But in no case is there major changes to the way we operate the machine.

The avionic regression failure is truly impressive on the A220, there is checklists and failure modes which take you back to some weird and wonderful setups. But you have to get multiple events usually involving electrics as well before you can't cure it by changing a sensor input to something else. And once you do then you get everything back but with riders that the system can't protect you anymore.

I was in at 4am last night doing volcanic ash and fire and smoke both of which involve pretty horrible checklists and failures. Compared to other types it was a breeze to deal with mainly because the checklists where ordered correctly and systems where dealt with in the required order. Instead of the pair of us having to make critical choices after having 20 hours awake after working 5 days in a row.

Anyway 2 days off now so I am away to find a beer garden today, will hit the books again tomorrow for the joys of autolands and 50 meters viz which is a new one for me.

Actually come to think of it last night with volcanic ash event which occurred over Norway we lost all 6 AoA sensors and all the airspeed indications one engine after having a dual flame out and being able to relight one of them, and the windscreen was screwed so all we could see out of it was a blur at 200ft not helped by having the masks on. We managed to get it down using 65% thrust on the live and -3,5 nose down, wasn't pretty but we stayed on the runway. It was basically keep it aligned when we hit 30ft take the power off pitch to 7deg nose up and wait for the bang and keep the thing in the middle of the runway with the rudder using the loc beam while braking like hell. Put the handbrake on and evacuate.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I hope that that was in the simulator.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Hey Alistair, I'm keeping up with most of your jargon, but care to edit the above for typos? I couldn't quite make sense of the last bit:

Quote (Alistair Heaton)

Already had words with man about they are on there tod outside keeping the aircraft safe
ponder cheers

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Sorry had a rare day off and on phone. I deleted it because even i couldn't understand it.

The sim is running 24h with 1 hr a day down time for a reboot and maint.

The cockpit dynamics in a lot of company's after lay off's has changed with experience increasing but the gradient of experience possibly changing due to seniority lists

It gives the possibility that the person in the FO's seat has significantly more experience than the person in charge of the aircraft which gives plenty of scope for conflict.

Yes the above situation was in the simulator. The western aviation industry does not as a rule train people in the aircraft. All these scenarios are dealt with over a 3 year period with 2 4hr sim sessions every 6 months. On initial rating you cover all of them while learning the various systems and the relevant failures and checklists and methods of dealing with them for the particular type. As history dictates with real life situations and accident/event reports they add in different scenarios. The current big one in Europe is stalling in landing configuration and wind shear. I don't think its a specific event that triggered it just that the safety folk in the regulators are seeing a trend that crews need this area revisited or reinforced. In the past things have concentrated on avoidance not actually dealing with it now we are doing both.

The volcanic ash is a good multi failure exercise which gives powerplant, electrical, instrumentation and limited visibility issues and if they think your up for it they can throw cabin fire in on top. Its pretty full on for 30-40 mins. Quiet a few company's use it to asses if the person is ready for upgrade to Captain.
My sim partner is also another experienced Captain so we got the full works thrown at us. If the crew was two 200 hour first officers on their first type rating they will limit the failures so its manageable for there experience level. ie they will cover the same individual scenarios just not all at the same time.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Alistair Heaton)

Sorry had a rare day off and on phone. I deleted it because even i couldn't understand it.
roflthumbsup2

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (NDTV)

US Regulators Complete Test Flights On Boeing 737 MAX
While the flight tests in Seattle are "an important milestone ... a number of key tasks remain, including evaluating the data gathered during these flights," the Federal Aviation Administration said Wednesday.
Link

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Just an update with the training requirements that are current just now.

https://www.flightglobal.com/airframers/american-p...

Don't have a clue what will be required in the USA.

In Europe its looking like a new type plus differences training as is now the case between classic and NG 737 models.

This is god news in the grand scale of things because at least they have a target to meet and they are providing probably more than they have to.

Bad news is that pretty much globally every one doesn't want new aircraft especially with the current oil price.

So some pretty major orders are entering the courts to be cancelled. I only know the European side of things. But the major order number of normal types has entered court to get the money back from deposits and the other major order the aircraft has never been certified yet.

I wouldn't be surprised if under 2500 airframes are ever built. And out of that over 50% of them will be taken with complete reluctance.

BTW airbus are completely screwed as well with its order book just none of its customers have an excuse to cancel.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Maybe this time pilots will be taught what Memory Items means and how to use the trim button on the wheel. For certain they did not get that the first time.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I presume they will, but as its so far completely away from a normal aircraft it will remain a special. I certainly won't be effected by the training requirements

It will have its own set of required scenarios which will more than likely go over into 3 days every 6 months which will kill it. Not that its not already dead anyway.

Utterly pointless me training for most of this stuff I can trim from high speed end to low speed end don't have a physical limitation and neither do the 60kg females I fly with what ever speed we do. The electrical trimmer never gets killed from my direct inputs. Well it does but its 3 or 7 levels down depending if you want to count all three PMCC computers going tits up as one failure if one goes, or each one a failure. Which is way way outside 1 in stupid amounts of millions flight hours. And even then we have three backup systems and the 737 has a sum total of cock all.

737 max one computer going tits up and your on your own.

Your choice as punters I won't be flying them then thankfully. I suspect it will be extremely doubtful I will every strap my bum in the back of them either. I have a choice I suspect most of you won't.

Its got one chance now otherwise its dead. It won't be my life online I will tell you for that much. You Yanks can be the test pigs.

II can't see any Boeing successes with software in the last 10 years be it civil, mil or space. I am pretty confident we won't see a success now. But I would utterly love to be wrong because only having one hardware provider is not good for man nor beast.

BTW the only memory item I have is put my O2 mask on in the event of explosive decompression. Just one the 737 pilots have double figures worth of memory items each of which is 7-12 items long. As a pax in the cabin, why the hell would you ever trust your life to one if I won't as a pro pilot.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

BTW the trim doesn't work properly because they can't fix it....... And now your into arguing about should an aircraft be aloud to fly without it being fixed.

My view is it should be fixed, and me and my family won't go in one until it is.

Its personal choice.

Enjoy flying untied and Airsouthwest....Because i suspect they will be the only ones operating them for quite a few years. And its not because they want to.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I am conflicted.
I won't say that i will never fly Boeing.
Those are words that I don't want to eat.
How much will I pay to avoid flying Boeing?
I will easily pay 10% more to avoid flying Boeing.
How much more will I be willing to pay?
15%?
20%?
That is my conflict. How much more than 10% will I pay to avoid Boeing?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Alistair - your puddle jumper doesn't do Mach .85 so the trim range can be limited to what you can handle. In any case, the trim situation has been repaired. The main thing exposed is carelessness in training; PIA 8303 emblazons that for all to see. For certain after I read the Lion Air report I could have been dumped into the Ethiopian cockpit out of a burlap sack and handled the situation without problem. But that's from reading the AD, the FCOM update, and the Lion Air preliminary report. It's sad when professional pilots refuse to act in a professional manner and do their homework and worse when the CAA of their country is part of covering up that lack of training. Feel free to comment about the FAA and Boeing, but the Ethiopian CAA were given clear notice of a potentially fatal circumstance avoidable by training and did nothing; neither Boeing nor the FAA had any information the design decision could result in the loss of an aircraft.

By the way - the electric trimmer was never necessarily disabled from working. The pilots chose not to use them. The action was no different than an intermittent short circuit.

Airbus software - https://www.flightglobal.com/programmes/airbus-rev...
Seems like they rushed it out the door to make money.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Max speed of Mach 0.82 but its more limited by transonic flow than anything else. We never go near that to be honest.

Range over 3300 Nautica miles.

They haven't repaired the small manual trimming window of airspeed. And electric trim still has a single failure mode redundancy.

BTW I wouldn't avoid Boeing. Just wouldn't fly on a MAX for a very long time until its been proved safe.

And I actually completely agree with the comments about the regulation and training world wide. How to tackle that one I really don't know.

I also think that they need to completely go through the Grandfather rights about what is actually allowed and what is required to be completely revisited with every new flavour of aircraft in a series.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It's not the trimming window of airspeed - it's the amount of mis-trim that sets the load. Letting 90 pounds of trim force build on the wheel before you try to trim manually is a problem. That's your redline speed, not normal operating speed where you normally trim, or have you moved from the Dash?

Ground all the Airbusses until all that defective software has been repaired. Obviously if a flight instructor can crash one just touching the trim wheel they are a death trap in the waiting.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Moved from the dash to A220, spent the last 3 months learning the new aircraft.

100 hours on the ground school for the aircraft plus another 50 hours company course on SOP's and emergency equipment and other stuff.

75 hours in the simulator.

There are various events that the aircraft goes way out of trim in seconds and you need to get it back ASAP, Upset recovery happens every 6 months for the last 10 years brought on after the airbus crash after 9/11. A variety of events can trigger it from post TCAS event and wake vortex through to thunderstorm, ayssemetric slat-flap failure can also be a bit of a bitch and trigger it. The main reason why you get hit by it though is wake vortex off other aircraft which in real life happens every couple of months. Never had it in real life as bad as the sim, but you can get easily 100 knts of airspeed change in 1-2 seconds either way with above 30 degs bank and +- 30 deg pitch changes in sim and attitudes requiring full control inputs before they develop in real life. Its one of the exercises we get every 6 months. Its one of the exercises the sims are not really able to do because they can't do G forces and most of them the motion system can't react fast enough so the visuals/instruments get out of sync with the motion until you get things back near normality. You can't do it in the aircraft because its nearly impossible to set up and you would end up bending alot of airframes. There is some specialists sims out there but they are not type specific that can simulate G force but they involve huge rooms with centrifuges and are mostly used for mil fighter pilots and research.

Sometimes you have no choice in the matter what energy condition your given the aircraft in . You just have to get it back to something sensible.

Even though the dash is turbo fans in some ways its closer to a swept wing jet than other turboprops only the saab 2000 is in the same class. Its limited to FL250 by regulation due to most of them not having drop down masks in the back. But its more than capable of getting up to over FL320. Its max speed is 280 knts compared to about 330 knts on a swept wing jet. The main difference is the amount of drag we can configure which is due to the props that can act as colossal air brakes so we can get away with murder with energy management. They tend not to make a fuss with experienced Dash pilots with transition to sweptwing jets compared to transitioning from say an ATR turboprop.

The main issue with the 737 NG trim is the redundancy level. The older classics had two trim motors and the pilot electric trim was a completely different circuit to the other automatic trims, Different power source and wiring. With the NG they did away with the second motor. So your left with 1 which everything goes through. Kill the power to it for what ever reason and the only backup it the pilot who has a limited window they can operate it in. Which is actually a downgrade from the 737-500 which had an extra level of redundancy. Plus they also increased the size of the stab and decreased the size of the wheel. So in effect made the window much smaller

I am pretty certain that the 737 product range is now dead and this situation of having a single redundancy level linked with a window of pilot ability to trim will never be allowed to happen again.

I still don't have a clue about proper FBW airbus. The Bombardier FBW logic and philosophy is different. But you can tell that they committed significant resources in the human factors side of things and the whole human interaction with it in various states. The people that have flown both say that the Global and A220 is about 20 years ahead of Airbus FBW. Its about time Airbus got together 30 odd human interaction specialists plus users plus engineers like Bombardier did and sorted out all the issues instead of sticky plaster fixes when ever a snag surfaces.

As with all these things the safe stats tell no lies.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It's actually a large enough window. It's just not normal to let the trim exceed such a huge amount. For certain the Lion Air pilots had no trouble making their 90 minute flight on manual trim.

I expect the original motors were brushed motors replaced with a far more reliable brushless motor. No incidents seem to have happened to an NG over the change. Ever.

Did Bombardier handle the spilled coffee problem? I mean, it was in a 1950s movie and even now Airbus aircraft can crash if a misdirected cup is spilled.

Weird that Airbus would not be some latest and greatest since their main selling point is cross-cockpit compatibility. How do they make that update without handing market to Boeing or Bombardier products? Well, now they can do the same far-too-expensive training to make the transition; ooops. The large airlines are shedding pilots like crazy so I expect it will be a while before they sell many.

I'm just fascinated that if another Airbus crashes the same as the one I mentioned - will every CAA ground them for a complete software review and dig though the relationship with EASA and have the press call Airbus callous money grubbing killers or are we stuck with a situation like the initial Lion Air crash where a minor maintenance problem is turned into a disaster by a combination of software and pilot error? It's at the same point that Boeing was working on a fix, but Ethiopian wasn't interested in either waiting for the fix or seeing their pilots got trained and caused the second crash. Small wonder Airbus has not said anything. I wonder what else they are hiding.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It's the a350 which has the coffee issue I think.

To be honest since I started doing multi crew with a centre pedestal it's pretty heinous crime to put any fluids near it. Most have procedures which fluids and food are handed rounds the back of the seat so they stay away to the side away from the pedestal. I believe now this is written in the FOM of all types now. Because if they don't have it and everyone else does then it must be ok. Bit like the cycling of controls in flight upset when the tail fell off the Airbus after 9/11. No aircraft will like 350ml of coffee spilled on it and it will create issues. It shouldn't though shut engines down. No doubt that a mod will come out with a water proof engine run switch and wire to the computer.

You have your view it's sufficient window with one level of redundancy instead of the two on the 737 classic. Seen so many aircraft Sims way out of trim due to various various factors. And we have had enough elevator authority due to it being a trim tab on the elevator or we have to go 6-7 items into the failure tree before we can't use the thumb trim.

This only the FAA flight tests everyone else is going to have a shot and the Canadians have already said they want a shaker silencers. And then we have the training requirements and cross type currency.

I think they will be lucky to make 2500 of them. I hope they have already started thinking about the next 737 replacement.

We are actually very much in agreement about training and the state of the current regulators and the current min standard. Where we differ is if this redundancy state is acceptable on a 2015 designed aircraft. And what the likely hood is a getting the world wide pilot population up to standard that the could deal with it and not kill everyone rather regularly. you can shout and scream as much as you like they should be able to. But it is extremely doubtful it will ever happen. You could of course limit your sales to countries that do maintain sufficient standards. But the your product would be dead as a dodo because you could never get the sales volume.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Aside from the attitude that software is cheaper, what effect would changing the fulcrum of the stabilizer have on the forces generated by an out of trim condition?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I'm still not believing the original 737 had dual stabilizer motors. Was any proof ever posted? The redundancy was the manual wheel.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Spilled coffee- sounds like the "pepsi syndrome" skit from saturday night live in 1979, where a spilled pepsi on the control room's operator console causes a nuclear power plant meltdown .Probably not so funny in real life.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The point is that, with the AoA response sorted, the MAX is as safe as the NG has been, including 3rd world underfunded training. And that Ethiopia had clear notice and did not need to train their pilots at all - just ground the planes and wait for the fix. As soon as they decided to fly, the risk was 100% in their hands. You just said they have full upset training all the time for rudder use in vortex shedding. Why are they depending on training to handle a software problem? OTOH, why didn't Ethiopian aggressively train the MCAS FCOM before returning to service? Just like PIA 8303 they did every single step wrong.

Still, in 2020, no aircraft control system should depend on a pilot never spilling a drop. Does Airbus not understand how water works?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It's 1 collosal Jack screw and the autopilot trim system electric motor and then the manual electric trim motor on a gear box then under that the gear and wires from the manual trim wheel. On the classic.

The Ng is smaller electric motor doing everything with the manual under it.

I posted pictures of them. On the classic it's a forklift and three techs to shift one. On the Ng is a two man lift.

The change did away with 3 dual core 20 amp cable runs from front to back And replaced it with a single core 5 amp signal run. So it was a pretty major weight saving.

It's pretty obvious why they did it. Max went one stage further than the Ng and took away the automatic kill switch in the front. You got all or nothing. Ng if the automatics took a hairy fit you could kill them but keep the electric trim. Which meant all the automatics went down to single layer before manual trimming required. But it was all through a single motor in the back you just killed one of the inputs to it selectively.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Btw there is over 5 pages of issues with the max. Nearly two of them should have prevented initial certification but we're undeclared to the regulator's.

It's not just MCAS which stopped it flying. It was the cause but things quickly escalate.

They put a huge number of crews through the SIM including the director the FAA. The majority of them were western legacy crew that had been flying 737 for years all flavours. That's actually what killed it and made Boeing give up arguing. The results will never be public but it really wasn't pretty. Over 50% of them ran the wrong checklist.

Once it's flying again it's not finished with. They will have to fit smart pitot tubes to it to increase the number of AOA sources. And there is a load of other stuff that will have to be changed within a couple of years.

From what I can tell the main wiring looms are going to have to be split. And control runs need moved. So every single aircraft will have to be taken back to metal internally.

You might have a few token airframes in the air by Christmas if the training side of things is sorted quickly. You will get new builds up relatively quickly but the old fleet is going take years to process. Then there is the storage snags which will be hell to sort out and cause many brown pants moment's with flaps and gear issues.

I agree you on fluids can get a fair amount of drips in the cockpit anyway with cold soaked airframes and condensation. The old Jetstream used have a river coming down the roof sometimes down the back of the overhead panel. Never seemed to kill anything but wasn't pleasant especially when it froze after a short turn round. Good for keeping ice cream frozen though on the grab handles which could get down to -20 Deg in flight. The q400 they were much warmer with no risk of sticking to them.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Spilled coffee, spilled Pepsi.
There was an incident about 30 or 40 years ago in a British Columbia pulp mill.
An operator spilled his coffee on his keyboard.
This caused some unintended control actions.
The ultimate result was an unexpected release of chlorine gas which poisoned some workers in a normally safe location in the plant.
As I remember they were rendered unconscious. I don't remember if there were any fatalities.
The potential for lethal consequences is very real with large amounts of chlorine.
Chlorine was one of the gases used in WW1.

Quote (Wiki)

The first killing agent was chlorine, used by the German military.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

On the Max it turned out the disable switch did not matter. The pilots did not use the trim switches to maintain the plane in trim even though powered trim was still effective, even after allowing 90 pounds of mistrim to accumulate. I know going off on tangents about things that might also have happened and have, in fact, not happened is an entertainment and adding straw to the strawman. The fact remains that the electric trim system did not fail; the accident pilots chose not to use it. The successful flight did use it correctly.

Any pilot failing to identify the correct checklist after two crashes should have been kicked from ever flying again, assuming they did not do the right thing and resign. I think that was clear on Atlas Air 3591. Two major crashes and anyone failing after that? It's not the airplane that causes that.

I would like to see the test evaluations myself, rather than second or third hand rumor. Was it a failure to follow in robotic fashion but still operate the aircraft safely or was it let go of the wheel and let the plane crash? Oh, of course, the main human factors and training failure event of this century will be withheld; no one would want that to get out to avoid the same thing happening again. (That's sarcasm)

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I don't blame you for wanting to know. i would quiet like to see them as well. There is nothing out there just a few rumours which are 5th hand plus.

I very much doubt it will ever be made public due confidentiality clauses mainly from Boeing and FAA.

As I said apparently it wasn't pretty even from instructors on type from top of the line Airlines which you would expect to have the best pilots on the market.

I think it was more failure to identify correctly the situation and failure to follow the required checklist to the end. No fatal crashes occurred and that was the public statement and there is no evidence to prove otherwise. The MCAS simulations as per the accidents with pre warned crews were also rather aerobatic for comfort.

The QRH for the MAX is truly horrendous to navigate. Its thick as hell and there are multiple combinations and choice points which way you go.

My current ECAS runs a red white and yellow system with a pointer next to the most important checklist to complete. Things are deferred to descent and approach and landing checklists as required. There is no memory involved. So we do all the red checklists, then we do the white. Then the yellow cautions. When we hit the decent and approaches it changes things for the none standard setup same as landing. If things are sensed they are setup correctly they are missed out.

The max could have had the same system, which is in the 777 and 787. But it didn't due grandfathering and the ipad training requirement.

Like it or not and arguments one way or the other, there was multiple failings of the certification process. The aircraft should never have been in the air. 30 mins on an ipad also was not valid as far as training went. It was a combination of large customer airlines and Boeing prioritising money over safety.

The current series of electro powered sims have been found to be under powered on certain controls compared to real life. Pilots have the strength to over power the actuators which then register a displacement which then give a control deviation. In real life you get wire stretch and then its rock solid with no movement. Quite what they are going to do about that I have no clue.

Waross its been a on going issue since I was in nappies fluids and control panels. History never seems to be learned from. I must admit most control rooms over the last 30 years there has been a ban on fluids. For me that goes from Biscuit factories through to Nukes. And if they had to be brought in then it was under a work card system even cleaning fluids for the floor. I will say I haven't seen a spill on a central console in some 13 years flying, and that one when it occurred was on a old analogy machine and required a complete strip down. And the amount of electrical gubbins in it has stayed with me ever since. Lord only knows what the current central pedestal has in it. I have described the machine as 200 computers flying in close formation. Even the Canadians just laughed at that comment In general most drink bottled water and coffee comes in cups with a lid in cockpits and goes no where near it.

But even with personal practises to try and prevent accidents things happen. We had a accident with a UK mil Airbus where someone put a camera into the area around the control stick and aerobatics occurred. Millions of pounds worth of training, military discipline for 20 plus years and still such a basic don't do that root cause occurred. There are a sizable group of people sticking up for that pilot as well who was court martialled over the event.

To be honest what the pilots did or didn't do in the two accidents hasn't been the focus for some time now. There has been that many findings since that apart from a few voices saying it should never have been grounded in the first place pretty much everyone has given up pushing that line. Even the Boeing PR machine has realised its not working. USA market is not big enough to carry the product by itself so either keep the international customers and regulators happy or don't fly it. Home politics on the subject are pretty much meaningless.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Don't want to start another thread about pilot incompetence.

Just reading about a aircraft atr managing to come into contact with the sea after the crew turned off the protection on approach.

How the hell they escaped that one I have zero clue.

I actually have alot of feeling and agreement with 3D on the subject of crew standards and training. Unfortunately I have zero ideas how to change the current situation.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

If it wasn't pretty there must have been a rash of resignations. A misplaced wire could reproduce the same situation. I wonder why no one said anything about their failure.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

If there is a rash of resignations then the planes don't fly.
If the planes are limiting due to compete crew then the price goes up.
If the OEM's are willing to limit supply to compete airlines then the price goes up.

Or do you want bucket price tickets and zero crew competent. Most punters want bucket prices.

So either the OEM designs for zero flight crew competence or they die due market forces your choice.


RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

As for the ATR crew that let the machine hit the water. I have zero excuse for that, its mind boggling to myself.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I'm sad to think that the CAAs of many countries around the planet depend on a comment here. Sort of makes my point.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I assume in your post of 2037 you mean competent instead of compete?

Any way I do wonder here in terms of the mcas fix whether the cure will turn out to be worse than the disease. Turning an aircraft never designed to FBW into a semi FBW is going to result in some unforeseen crash. Either it will freeze or mcas won't become active when it needs to.

Sure this has escalated beyond one issue as people dug more into the design and certification. And some of those fixes would have meant fundamental redesign.

AH is correct. Most punters just want cheap tickets. But if another 737 max falls out the sky because of design issues and it gets highlighted then that could be an unstoppable demand for other aircraft.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The issue has morphed into something way beyond the original issue.

Hopefully they will release a full list of the eventual changes.

And once it's done then hopefully they will look at the regulation big picture.

To be honest the money involved is small in the aviation scale of things. With the tech work to fix the issues in the design office. It's the change to the dry operating weight which is the biggest issue. And will give a clue to how much has been added.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Another near disaster from Airbus: https://www.flightglobal.com/safety/pilots-dual-co...

Lack of human factors studies and failure to allow inputs from one pilot as force feed-back to the other pilot. Seems like a cost savings move to not include haptic feedback to get the pilots on the same page. It's FBW. Yet again, hero pilots triumph over poor systems design.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

When one reviews the widely changing quality of posts by a particular poster, it suggests that some posts are being made in the local bar after 6 pints have been consumed.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Ouch! poke

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

(OP)
AH,
Perhaps when you take a second look at your post from 14 Jul 20 21:01 you might want to edit a little. It's the kind of thing I normally red-flag for deletion. Maybe a warning is appropriate here. I will look in tomorrow to see if it's cleared up. If you need clarification, please read the posting guidelines (link on the bottom of the page).

www.sparweb.ca

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It's deleted and yes number of pints involved.

Personally I do think the fundamental rules of fly by wire need revisiting. With the main controls not connected you get no feel what the other is doing.

We have a very loud dual input sounded if the system see's it. Plus it gets flagged to the safety office via acas. You can kill the otherstick. And the inputs are sum so if one puts full forward in and other full back nothing will happen.

The not following TCAS has been around for years the Swiss DHL and subsequent murder is case in point. It is again an every 6 month exercise. To be honest I don't understand why. The system takes into account performance, It can deal with 8 aircraft at the same time. It gives you green and red bands to nail. If you do everything works. You don't have to think. You don't have to react particular fast either. 45 second to disengage the ap and pitch. The boxes speak to each other and combine the solution to the least aggressive that works giving 300 ft seperation. When you have multiple involved it can get a bit more technical with reversions requiring quicker changes but it's still hit the green band on the vsi and everything works.

The TCAS stuff is none type related but the fbw dual input is common to all side stick types with no connect. To be honest even when connected two pilots fighting over control has always been an issue.

Per say the same thing could happen on multiple different types


RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

AH - You deleted the wrong one

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Mo and didn't see it, now dealt with thanks.

It should have been more politely worded.

More than fair call getting my knuckles rapped for it.



RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I'm still wondering if all these relatively cheap software mods are going to cut it with everyone else. I've not seen mention of any other hardware mods as part of the return to service work.

The base design of the max to fit the bigger engines resulted in a cascade of issues which were downgraded to meet an impossible "no sim training" requirement.

So on the shopping list for (non US) regulators is surely:
1) Stick shaker disconnect / cancel (Canadians want that?)
2) Separate isolation for the stab trim motor for auto controls and manual controls ( i.e. back to the NG)
3) Something that tells the pilots that MCAS is active / in operation and a cancel button
4) Those software mods to stop the thing activating every 5 seconds multiple times
5) Those wiring issues and other things on the long list
6) Does this semi FBW approach (1oo2) actually work or does it open up other failure modes / conflicts


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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

1 the Canadians are going for it big style with the stick shaker.
2. I believe its taken care of via 2 flight control computers and its on the list of want requires to happen in the next 24 months.
3. They already have the AOA for free no charge and its link to 2.
4.its been stopped one time only activation. What happens to the flight envelope is any ones guess.
5. Nothing said apart from it fixed to within requirements nobody has clue if they have fixed it or not but we suspect they have.
6. I really don't have a f'ing clue, its a Frankenstein setup which is not legal, but it soon will be. And will have been created to allow the 737 Frankenstein to fly. It won't be repeated. economic and political reasons will be the prime mover which is why my bum and my family's will never strap there lily pink or hairy bums in it for a right few years until proved safe. The mother in law can fly in it with no limitations.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

BTW its not just a cheap software mod there is poo loads of changes occurring.

Quite how much is not common knowledge. We might get the full changes through me and spar knowing what documents to have a look at from both sides of the divide. The control runs and electrics will not be in the pilot realm. We shall see how open they are about the changes. So far from 6 month's ago since the FAA boss screwed up completely in the sim according to 6th hand reports and went WTF is this. Boeing have been remarkably open apparently.

BTW beer alert... I have had a few sorry spar.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

But what we do know thought is that the 2 inch thick QRH is here to stay. Finding it and navigating to the right page is what every pilot will have to do. So 27 memory items they will have to find a book behind a seat and have to decided what the hell is going on after doing 12 hours for 7 day in a row.

which over 60 percent of Boeing selected pilots screwed up monumentally. And most of them were not third world. And one of them was the faa director.

So enjoy your flight in a 737 max...

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

That ain't never gonna happen. Boeing rolled the dice on that design and they were not playing with their own chips. I prefer to do my gambling at the card table rather than at 3500 ft. It's the principle of the thing. This is software defined aircraft. "The die has been cast." Julius Caesar

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

its a software design aircraft and operated but its 1960's design. Fudged to meet 1980's standards.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Alistair, all immediately crashed; just shoved the wheel forward and went TOGO thrust at the same time?

Is that the screw up? Not knowing how the trim switch works or how to read the trim dial?

Knowing this only 7th hand, it seems like the Telephone game + conspiracy theory making a story people want to hear, rather that a clear factual record.

I'd believe it if told they missed a step, like disabling the A/P soon enough; in the original software the problem only happens when the A/P is disabled. But I would be mystified if the proper response to an alarm was to nose it over and make it crash, unless one was in a position to cast blame outside the organization they head in an effort to get increased funding.

2) Separate isolation for the stab trim motor for auto controls and manual controls ( i.e. back to the NG)

This is wrong, at least in terms of the crashes. The pilots chose not to trim, so isolation did not matter. They knew the trim switch would override the MCAS inputs; the Lion Air pilot did it dozens of times. The Ethiopian pilots did too. Both crews let the trim error accumulate and the wheel force accumulate and did nothing with the still working trim control to affect it. It would happen just the same with a wiring issue in an NG and the separate switch would make no difference to pilots ignoring the controls and indicators. In fact, Ethiopian re-enable the trim motor and did not adjust the trim, in contravention of the instructions.

There has been no report by anyone that a fault in the NG was safely handled because they were separate and, in the NG, the pilots were trained to shut them both off anyway rather than diagnose the problem in-flight. If there is a problem in the trim switch itself, what good is shutting off just the automatics.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Apparently over 60 percent of them ran the wrong check list.

This is a black and white issue. Wrong checklist wrong direction.

Nobody crashed. There were a ew engines shut down that were perfectly serviceable but such is life. All commercial pref A aircraft can fly on one. So its no big deal.

But the main thing is that over 60% of the operators from all nationalities could not diagnose what the hell is wrong with the machine when they were fully rested and geared up for an important sim session. If you can't get it right from those conditions you have zero chance at 4 am body time on day 7. They had zero clue and ran the wrong checklist.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

That's it right there. If you can't diagnose what the heck is going, no checklist is going to work. Plus the more checklists you have just increases the chance of selecting the wrong one.

I crashed an ultralight. Actually two and almost 3, but the first is most relevant here. I'll save the other stories for a later date. It was a very high performance type at very low speeds. Furthermore it even had a specially designed Robertson STOL package installed on it. Takeoff speed was 15mph. I took off in a bit of a strong headwind, started climbing at 1000 fpm and when I looked down, I had a negative ground speed. I looked up and there were a lot of clouds. I thought I was in some kind of a climbing, power on stall, because negative GS and 1500 fpm climb really gives one a weird perspective when trying to analyze what was happening. I pulled back power and lowered the stick, but it turned out that I was still too close to ground and landed HARD! OK, really hard. Fortunately with the slow forward AS, headwind and negative GS and my fast reaction time, I still landed on the strip. Point is, if you don't diagnose correctly, even flying within the envelope doesn't work.

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

So - it's not unsafe? How did they determine that an engine should be shut down? Was it the Atlas Air pilot?

It's still 7th hand. Telling me exactly how they came to use the wrong checklist when they were there for only one reason is where the truth is. Running the wrong checklist is about 99th on my list as long as the pilots keep the plane out of the dirt. And you just said they all did. So now it's not a plane problem. It's a pilots problem.

I don't want a pilot to diagnose anything. That's what has crashed any number planes when crews get to figuring out what's wrong.

A checklist is the opposite of diagnosing things. It's an "if this happens do this thing," to avoid the pilots having to think. Like "If airspeed is greater than VMo, reduce thrust". But I don't know about "If the wheel is pulling too hard and you aren't doing a loop use the trim button, the one under your left thumb, right where it has been for 500 to 20,000 hours. Press until the load is GONE." Is there a manual entry for exactly how far to pull the wheel back at rotation speed?

I want the plane to be operated safely. I know there was greater than zero chance as one crew, without any hints, flew safely, another half crew flew safely until the new guy took the wheel, and a third crew - by the checklist they half-recalled - piled it into the ground. From Atlas Air it's clear the FAA is no longer concerned with incapable pilots getting in the seats. And from PIA 8303 it's clear Airbus has no answer for that problem either, triple redundancy or not.

Maybe it's time for cockpits to have three pilots with duplicate controls, all making inputs, and then a computer cuts out the one that disagrees with the other two, maybe gives a high-voltage shock to let them know to let go.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Checklists will direct you towards various procedures. If the checklist you have taken is not correct you may end up doing the wrong thing.

The classic on the Q400 is a bus failure if you don't spot it within 30 seconds then generators start going off line and pretty much half the board lights up and screens drop out and you have a choice of 8 checklists depending which red light takes your fancy. The bus fail is actually a single amber light and if you go for that checklist one switch is set and everything starts working again. I think 4 out of the 8 checklists will end up with a engine shutdown because you loose oil pressure readings and various other things. Its a well known feature which type rated pilots should know about. But even if they miss it and shut an engine down nobody dies.

Its one of the joys of flying a stretched grandfathered machine where they had to change things to keep differences training instead of full type rating. Which in the Q400 is 2 sim sessions and half a day of ground school on performance if you have flown one of the other flavours.

It obviously unsafe to have a single component failure result in a fatal crash what ever the process is after that. The threat should have been trapped by design. That premise has been around since the 737 was first designed in the 60's. There are somethings you can't have two or more of encase of failure such as wings and hull so you build them to not fail. You have others that their failure will not kill you so you don't need to double up on.

You would need 3 computers and at least of 3 of every sensor supplying data to them. One just doesn't cut it. 2 is marginal.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Checklists are not concerned with diagnosis. They have no if, then, else paths. They are the last item on a diagnosis flowchart.

Simplifying a 50-60% success ratio of the man-machine interface is indicative of results obtained from blindly choosing between two alternatives. It needs to be something over 99.75% Any monkey can pull off 50/50. Considering that the pilots are supposedly the highly trained half of a 50/50 combined man-machine system, they typically get acceptably high scores, yet the mission failed, means that the machine isn't contributing to success at all.

A machine with a 50/50 success ratio needs 8 redundancies to get 99.5% chance of success, but then as they say, "A man with 2 watches never knows the time". Is putting your faith in 8 watches the answer we're really looking for? 8 machines at 50% correct voting yes or no still results in a tie. Guess we really only need 7.



“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

"It obviously unsafe to have a single component failure result in a fatal crash what ever the process is after that. " Yet here we are, with a 737 Max with a single sensore being used to feed the MCAS. It is obvious, yet we persist in believing the emperor is wearing clothes.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Flight says NPRM coming out for the AD to lift the grounding.

Pt 8 on it's way ?

IMHO if we want to improve safety the best thing is to stop grandfathering. Types have a production life of 20 years, and need to be updated to continue production. That'll stop a 1960s design being "lipstick up" in the 2010s.

another day in paradise, or is paradise one day closer ?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Nothing about the 737 crashes was due to grandfathering. But I bet makers would like to see all 20 year old air frames taken out of service.

It occurs to me that the FAA is covering for a huge foul-up. All software will be under both version control and be stored in a software vault, the sort of vault that can generate messages when the software is updated in the form of e-mail notifications. Why did the FAA reps fail to be notified by automatic methods? Or were they and they ignored the changes to MCAS and are seeking to hide that they were in fact informed? It would be what a quality conscious organization that is delegating would do to ensure that there was a correct communications of changes.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Three pilots, all with hands on duplicate controls would have prevented the PIA crash and the Atlas Air crash. Multiple computers are obviously insufficient.

Alistair, you said the 737 pilots shut down engines in response to a stick shaker and stall warning. I don't care about the Q400 and electrical bus failure. Why did the 737 pilots do that?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

i have zero clue about the 737 NG systems or checklists similar to main line Airbus systems.. I don't know what system failures require decision points. I do know though that it doesn't have a central CAP which means you have to scout around the cockpit and see what lights are showing and then find the checklist and decide which checklist to run once you have located the book. To be honest single engine is not that extreme compared to having to use standby instruments to fly.

They have been extremely closed mouthed about what was actually thrown at the pilots in those sessions. All we know publicly is that pretty much everyone gave up about the Ipad training differences training and also a lot of the major changes to the avionics after that set of tests. They went dual flight computers quiet soon after that.

Per say grandfathering still has a place but it should have a limit before a large picture look at the complete device to see how all the parts fit together. There should also be a limit when certain technology's can not be omitted due to being limited because of triggering none grandfather testing and work due money and marketing.

Now there is two AOA in the mix with the dual primary FCC in the mix, if there is a disagreement between the two then MCAS won't fire. I presume there is a whole raft of new checklists to deal with the computers not agreeing. This is only a temporary fix to get it flying again. Within a certain time frame they will have to swap at least two of the old school pitot tubes for smart probes which also measure AoA. How many of them they will have to swap I have no clue but I would think at least 2, which will bring it up to 4 AoA sensors but it could be all of them to get rid of the piping.

But again we are just talking about MCAS, it is the primary cause of the grounding and the cause of all the deaths, But in reality it is just one item of many which meant the plane should never have been certified in the first place. The flight tests are only for ungrounding in USA airspace. The training still hasn't been finalised. The other world wide regulators also have not had there say. I know Canada has a few issues which will need resolving around the stick shaker which I can't see the other regulators disagreeing with. But in reality the MAX may look the same on the outside but is completely different beast on the inside with major changes having occurred.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

How long until they bite the bullet and scrap this line?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Nevermind. I see no one cares how the FAA should have dealt with MCAS on a limited number of FAA inspectors.
Weird I thought I had a post about the FAA process. Has it gone missing for some reason?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Its a given that the whole Regulatory process was completely flawed producing the MAX. I also agree with you that the world wide standards need addressing as well both maint and pilot standards. Quite how you do that from experience working round the world with the different cultures involved I have no clue. The only way i can see is by limiting the sales market and just not allowing them to operate in certain regions of the world. You have to design for the min standard that will fly it or prevent them flying it.

There was also an element of keeping information from regulators and not doing what the regulations require. That's an internal issue for the USA to sort out.

The line won't be scrapped. They will have to provide support for it now until the end of life cycle even if they don't want to and it will cost money to do so. I would love to be wrong and after this is finished with it turns out to be a successful type.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Imposing sanctions on countries that won't accept the results might cross someone's mind sooner or later. They think it works for pipelines. https://foreignpolicy.com/2020/07/20/nord-stream-2...

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I am sure it was on the table with the old Boeing exec and FAA bosses.

After the second crash then even sanctions couldn't prevent it. Then they had a choice let outside countries control the recertification or retain it internally.

Remember the new 777 is due soon and its market is extremely limited domestically.

Having two product lines domestic only would be killer. Plus it would end up two type designs per product which is back to the old days of the 80's

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

"keeping information from regulators"

That's just it. The regulators had to willfully avoid getting that information, much the same as the Ethiopian CAA avoided doing their job.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Don't have a clue about that side of things, but doesn't change the point that it should never have been certified in the first place.

FAA wasn't doing there job and neither was the Ethiopian. And Boeing certainly wasn't.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

This came out Yesterday. Expect quite a few of these with all the aircraft groundings recently. No per say the MAX but all of them will have similar issues after being on the ground so long. Expect a heap of gear and flap issues as well. TO note all types will have issues not just the ones mentioned. It will just take time for the issues to surface.

https://rgl.faa.gov/Regulatory_and_Guidance_Librar...

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

As an interested observer, I and I suspect others, am wondering what is the function of this check valve that makes it aircraft type specific rather than engine specific.
Thanks.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The bleed air system is aircraft not engine. The valves on the compressors stages will be engine. But like the hydraulics after the output of the engine driven pump its then aircraft.

The bleed air system basically uses compressed air from the compressor. depending on what power setting the engine depends on which compressor it takes it air from. generally low power settings and it will take from the HP compressor but high power then the low pressure compressor will have enough. The check valve stops air from the HP going through the system back into to Low pressure compressor when the HP bleed is open. If it manages to it upsets the aerodynamics of the LP compressor and you start getting engines stalls or only surges which require a shut down.

It sounds like the check valves haven't changed since the aircraft came out and are a common part. If they work there is no reason to change them in the design. Normally that area is warm so they won't have condensation forming in the pipes. Now they will have sat for months with water in them on the valve.

But per say this isn't Just a Boeing issue all OEM's will be having issues with seals going and valves sticking.

There is a lot of power taken from these bleed systems. They run the hot wing icing system and also power the pressurisation and air conditioning for the whole aircraft. The air coming out of them is hot 500 deg C plus. And is you stick hot compressed air into the LP compressor it will stall it, which will decrease airflow into the combustion chamber which will then spike the exhaust gas temp and melt the rear turbines. If you kill the turbines you have nothing to drive the compressor drive shafts so you stop compressing and very little power can be produced from the engine and usually it flames out.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The language they use is interesting.

What is a "forced off airport landing"?

Catastrophic crash in normal English?

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Yeah.
Ridiculous wording!
Obviously has difficulty dealing with truth.
Where do they get these ... these ... Professional Obfuscaters?

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Thanks Alistair.
And a few other people who didn't ask thank you also.
From your explanation we can also understand how/why it is acceptable to fly with a check valve locked down.
Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Sully made a “force off airport landing”. The expression seemed to convey its meaning. The landing will be when/where it is with few options. Up to the crew to make the best of it. The closer to the ground the plane is when it becomes a glider the fewer the options; go around probably isn’t on the option list.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Then there was the Gimli Glider.
They landed on a drag-strip that used to be an airstrip.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

A forced landing is having to land anywhere on an unprepared area and you have to do it like it or not. Aircraft like gliders do it all the time. Powered aircraft less so and usually due to a mechanical issue. Sometimes its a crash and the plane needs fixed and some of the time the aircraft gets on the ground no damage. You also have a full fatal crash with everything involved never flying again.

Big commercial aircraft such as in the discussion it rarely happens and its even rarer that no damage is done.

IF the HP compressor valve is locked down shut it means that no high pressure air can get into the LP compressor. As such you will be fine in normal flight but at some points the LP won't be enough to control the temp in the aircraft, so it might get hot as hell on the ground before takeoff and on the descent. They will have ram air to help out with pressurisation. And more than likely a restriction that they can't fly in icing conditions which would need the high pressure valve open to drive that system while descending.

What I think has happened in this case is several aircraft have had to shut engines down which is a reportable event to all regulators. They have then strip the engine and discovered the corroded valve. Then then went and had a look at the other engine and the valve was in a similar out of limit state. There are enough parked aircraft about it was relatively simple to say get the cowls open on that one over there and lets have a look. It wasn't pretty either and a couple more to make sure and no point looking at others if they are all screwed. Maybe they got some in Alaska inspected and some in the south and they were all the same. Spoke to Boeing who said err they are all the same across all 737 types, Quite rightly the FAA puts out this emergency AD to get them fixed world wide ASAP before planes go flying. I suspect the reason why the English is different to normal is because it bypassed several stages which output of the FAA normally goes through to maintain image. No committee's involved in this one, straight to the director of the FAA who then goes on the phone to the Boss of Boeing to let him know before its public. Some technical type has written it, It will be proof read by another tech type then released. Zero media guru's involved just stop the aircraft flying before inspection. I wouldn't be to harsh on the wording. It pretty clear that if planes have been in storage then these valves have to be inspected before flight. And it gives a method to get them to a hanger to get fixed.

The English might be a bit dodgy but the emergency AD has got the required info out quickly and prevented any fatality's. I suspect it not the last one on various aircraft types which have been in storage.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Found out today that the check valve is a Boeing only fitted part which is common across the 737 fleet.

Any other type with the same engines is not effected. Apparently they had a look at pretty much every type that was in storage Apparently its not a big issue to check them or to swap out the check valve If you can get hold of the spare part. Which is normally not an issue.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Rumour has it that the MAX doesn't not comply with rags for stability and control forces. And requires a "special" for it to fly again with out the flight control computer system and sensors going FBW regs.

As things stand MCAS doesn't comply with the failure analysis numbers matrix. You have to go to the next level of redundancy before you get the required failure per million flight hours. To get that then smart probes have to go in and 3 flight control computers i am told.

The FAA is more than likely willing to give a dispensation, the other regulators are not keen. Nobody can go to the USA anyway due to covid and its unlikely that infection rates are going to drop to allow unrestricted travel to do flight tests for quit a few months.

The USA market alone is not enough to sustain the model if the FAA decided to go it alone. So I doubt Boeing is keen about just getting it flying again without it being world wide.

There is also some issue with the test aircraft being one of the small models. Most of them will be longer and heavier. And if the short one is twitchy they want to know what the longer ones will do before pax get on them.

The complete lack of "noise" after the flight tests by anyone gives a good indication about the state of play.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Well if that's only half correct it does look like the chickens have come home to roost, i.e. all those things they fudged around because of the bigger engines and short undercarriage (MCAS etc) and the fact that no one now trusts the FAA to do the right thing.

I've said before I thought this half way house between Boeing design and FBW could cause more trouble than the initial fault.

And all these new safeguards to stop MCAS operating (disagreement between sensors or FCCs, only operate once (per flight?)) means that it may not operate when it should and create a different hazard and is then itself a failure to operate correctly?

So they're damned if it goes off when it shouldn't and damned it is doesn't go off when it should.



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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Given the current state of affairs, I'd be surprised if international travel from/to the US opens up before 2021.

Maybe Boeing will followthrough with their threats and spin off the commercial and just let it tank.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There should be written a "lessons learned" chapter in some MBa textbook outlining how mindless devotion to profits and bonuses combined with a "responsive regulator" ( read corrupt) leads to self destruction of a company.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Littleinch)

o they're damned if it goes off when it shouldn't and damned it is doesn't go off when it should.


That's a pretty good summary I think.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The "hazard" if MCAS doesn't function is that, near stall, the pilots aren't given quite as much linearity as they haul back on the control wheel to produce that stall. Since the accident pilots were unable to detect or understand what it means to have more than 50 and up to 90 pounds of force on the control wheel I'd say that particular requirement is no longer useful and should be dropped entirely in favor of simply maintaining a positive stability margin into stall so any pilot not actively trying to crash the plane can just let go and the plane settle itself down.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (LI)

So they're damned if it goes off when it shouldn't and damned it is doesn't go off when it should.
I agree.
I have been concerned with that aspect for some time now.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Maybe a little worse than that, Dave.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (3DDave)

is no longer useful and should be dropped entirely in favor of simply maintaining a positive stability margin into stall so any pilot not actively trying to crash the plane can just let go and the plane settle itself down.


I'm afraid they can't do that Dave (Sorry, I had to work that in). That sort of redesign would qualify as a horse of a different color, and mean certification as such, or rebuild as an NG without the leap engine which doesn't meet the design economy case, as discussed quite a ways back. I mean they could but, maybe not a viable product any more if they did.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There is no redesign required. The MAX maintains positive pitch stability to stall.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The MAX maintains positive pitch stability to stall. ????

Quote (Dave)

pilots were unable to detect or understand what it means to have more than 50 and up to 90 pounds of force on the control wheel
What that meant and what was not covered in any training was that they were trying to fly a broken airplane with a very active and agressive death wish.


Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Taking replies out of context again? The stability is what happens when there is no MCAS.

Yeah - and they never learned that the trim button is used, as the first crew did, to offset wheel pitch forces.

How is that day-one-in-the-cockpit training overlooked?

Let's examine the Ethiopian crash report for details on the enhanced training they had after the details of the Lion Air crash were released.

I'll wait while responders look that up, but I won't hold my breath.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The control force decreases the higher to alpha critical they get. If it increased there wouldn't be a problem.

This reg about the control forces as alpha increases is one of the original and was enforce when the original 737 rolled out the hanger.

Basically you can't have the control forces decrease as the alpha increases. They used to test it with spring force gauges hooked to the yoke and the test pilot pulled back through them and read out he readings and it was plotted while decelerating at 1 knt per second in level flight when they got to Vref they stopped trimming then took it to stall. How they do it these days I have no clue.

This is different to stability which is the aircraft returning to the trimmed condition after the controls are released. At lower alpha it will do it quicker on the 737 max at high alpha it will still do it but it will take longer. But it will always return. If it was unstable it would never get back to the trimmed condition.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Alistair - the slope of the increase of force is not supposed to decrease. The force in the MAX doesn't decrease, it just doesn't increase as fast. There is no force reversal. This is Aero 101.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

For increase of alpha after as certain point requires less force input than the previous increase. If it was the same there would be no problem if it increased everyone would be happy. It doesn't it decreases which is the reason why MCAS was invented to artificially knock out the trim to keep the force the pilots feel the same or increase.

It definitely decreases because of the lift off the engines forward of the point of pressure creating a moment adding to the moment of the tail plane. This reduces the amount of elevator required to increase pitch. This decrease is not allowed under regulations. IF it was allowed they would have never have put MCAS in, in the first place.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Alistair - Now you've changed your tune, going from decreasing force (wrong) to decreasing force gradient, which is what I wrote. I know about the aerodynamics - that's what the "Aerospace" tag by my name means. Typically it's called center of pressure, but that's not a fixed location with variation in AoA. It does add lift ahead of the center of gravity, which is relatively constant if the only change is AoA, depending on the footing the flight attendants have with the drink carts. It is the position relative to the CoG that produces moment.

The thing is - in the two MCAS crashes the pilots were entirely immune to noticing control forces in any way that prompted the correct responses. With that human factors information the regulation makes no sense. In fact, without that regulation, MCAS would not exist and the crashes would not have occurred.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

yep we are now arguing about the use of English terms which is different between pilots and engineers and proper English speakers and American. The CoP does change depending what flap setting you have and AoA and the movement is more pronounced on swept wing it moves both forward and back and along the wing laterally. Calling it Point/centre name makes no difference

It really doesn't matter what the pilots did now. The plane was multiple sheets of A4 outside regs and should never have been certified in the first place. It was even none compliant with regulations which were in force when the regulations were first agreed. Not the grey we managed to get the NG out before the grandfather regs were enforced type of regs more than likely it broke them as well though. We will have to wait and see if they produce a complete list of all changes.

The thing was none compliant should never have been flying. Now is it it Boeings fault or FAA fault for letting it fly? I really don't care and neither should pax. The system is broken and needs fixed.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Actually come to think of it there is a difference between centre of pressure and point of pressure.

centre of pressure is the local effect on the aerofoil as a unit and given in % of cord and perpendicular scaler value , and the point of pressure is a group of aerofoils combined together and can be a vector.

So the Centre of pressure for the max wing will not change from normal with AoA changes. The point of pressure for the system will change with the max because you have to add the centre of pressure of the wing to the centre of pressure of engine cowls lift giving a point of pressure which you can then use to work out your moments which need balanced by the trim stab.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Early in this discussion there was a suggestion that at extreme angles of attack, the control force would go negative and beyond that AoA "hands off" would result in a continued increase in the AoA.
That post may have been in error.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Oh, I see what you want Dave-. A stable aircraft but non-compliant with FAA spec control forces because it's an MCAS delete. I agree without special knowledge as a pilot or working in a/c stability that that sounds at the very least, more predictable than MCAS, especially pre-disclosure. 'watch the new ones, stick sensitivity changes at high alpha', but then you're training pilots to fly wrt alpha instead of reference airspeeds, adding alpha guages to the cockpit display and so on. An aircraft isn't just something that flies, it a component of regularatory, logistical, economic and training systems, that's what this whole mess shines a light on.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

They don't go negative if they did then the plane would be unstable and that'd definably a regs fail on civilian air transport aircraft.

The Canadians have actually brought up the idea that MCAS causes more problems than it solves. But there is no data when this affect actually starts occurring.
IS it at normal approach alphas or do you have to go to stupid extremes to get the effect. But after bringing it up and an article was posted here about it. Everything has gone silent on the subject.

The military fast jets do actually reference to the alpha. never seen it in the civilian world. Some unlimited aerobatic aircraft have alpha indications but i have never flown one of them. Way way to expensive.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Yeah, I listened to an interview of a french rafale pilot and he said instead of using corner air speeds as reference they used alpha and thrust setting I think. Above this alpha you're losing speed, below you're gaining. In retrospect, that's going to apply in the maneuvering regime instead of fast and level. As an engineering student, it seemed to be the best reference because it's what the wing cares about. If you're light and fast or slow and heavy, alpha will tell you how the lift curve and induced drag are.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I must admit I tend to agree with you.

But to convert every pilot in the world over to AoA would be rather painful. And to be honest its very rare outside the sim that we ever go over 30 deg bank and outside 20 nose pitch up attitudes and more than 10 degs nose pitch down. The fast jet pilots are pulling +G in all attitudes where the picture of the horizon bares very little relation to the aircrafts energy state and AoA.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There are two forms of artificial horizon out there.



It has been shall we say rather painful and deadly converting pilots between the two methods when they have been trained initially using one method.

I have flown aircraft with a Russian artificial horizon but very quickly it was screwing with my head even though i was looking out the window. It was a good learning experience.

After 5 mins I covered it up and only used the window and I certainly would never attempt to fly on instruments using it.

Its not so much an issue for none Russians because they will never have used it. But Russians converting onto western hardware such as Boeing or Airbus it must be a mind screw for years.

I believe these days young commercial pilots in Russia don't go near it.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

just heard that the MAX product support world wide has been slashed. The UK and Ireland team has gone from 27 licensed techs down to 3.

When is the next stock market release by Boeing?

It seems that everything has to go through them, and not made public before. Something is going on but nothing said.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

From the news:

"The Federal Aviation Administration said on Monday that it is proposing requiring four key Boeing 737 MAX design changes to address safety issues seen in two crashes that killed 346 people and led to the plane's grounding in March 2019.

The agency is issuing a proposed airworthiness directive to require updated flight-control software, revised display-processing software to generate alerts, revising certain flight-crew operating procedures, and changing the routing of some wiring bundles."

We'll have to wait until the rest of the world receives these changes... It may be the Max is limited to US airspace...


Dik

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Anybody fancy going through 90 odd pages??? https://www.faa.gov/news/media/attachments/737-MAX...

Seems to be mainly MCAS software issues.

Discrepancy between sensors is 5.5 degrees allowable - seems a lot to me.

Section 6.6.has the wiring issue - No idea how much work is involved here??

A/P disconnects 1 second after stick shaker starts.

I love this bit - basically we don't have a requirement so the fact you can't turn the trim wheel is not relevant!! "Stabilizer Trim Wheel Forces comply with 14 CFR 25.143 by analysis per EASA CRI B-17
because existing guidance does not cover stabilizer trim wheel forces

Doesn't talk much about what happens if MCAS is disabled, but is actually needed, other than "Reassessed aircraft stall characteristics with STS/MCAS and Electronic Feel Systems
inoperative and determined the aircraft meets FAA requirements" - So why is MCAS needed??

Nothing about the stick shaker disconnect / cancel.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (FAA Report)

"Reassessed aircraft stall characteristics with STS/MCAS and Electronic Feel Systems
inoperative and determined the aircraft meets FAA requirements"

That is an odd statement...maybe the new software modifications mean the plane's handling isn't an issue without MCAS now?

Is it not weird that "Electronic Feel Systems" only appears in that one statement at the end?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It does say "stall characteristics", not pre-stall or high AoA, but is kind of flung in at the end.

I couldn't find anything really which addressed what happened if MCAS was inactive at these high AoA instances, but maybe it's buried in the report somewhere?

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

If they call it an anti stall system then they have no chance of getting it past certification. There is a whole raft of regs on that if it is.

AoA bounces around and depending on the gust and yaw there will be differences between the two sides. Although 5.5 degrees does seem rather a lot.

Seems they have a get out on the trim forces because no reg's cover it. And more than likely they can't do anything about them anyway.

The wiring changes on the machines in production won't be that hard to do. The ones already produced its a pretty major job. They can't leave dead wires in looms so will have to split the looms and then reform them. There will also have to be holes made/enlarged in pressure bulk heads for the new wire. Don't have a clue if they can get at said loom with out stripping out the interior or not.

The wording to me is that we have made Boeing do as much as they can with the design and we don't think they can do much more with it in any reasonable time frame. Next stage is start screwing around with the aerodynamics.

We shall see what the other regulators say about it.

I suspect we might be seeing it flying in the USA only for a couple of years.











RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (Alastair Heaton)

The wording to me is that we have made Boeing do as much as they can with the design and we don't think they can do much more with it in any reasonable time frame.

... without junking the whole design and starting again.

There is still quite a lot for Boeing to do based on that document wrt crew alarms etc and coming up with a training package.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

It's screwed in that regard it's still in the 60's.

It's a last of a kind Frankenstein.

Everyone knows if it doesn't fly again then Boeing commercial will go bust and screw the world.

To be honest over 50% the orders are gone anyway. They won't be able to dump them for cost price on the USA market even without including the initial design costs never mind the last 18 months.

You lot can fly on them if you like I won't be or the family. The mother in law won't know mind about the ban though :D

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Some interesting divergence going on between regualtors

https://www.industryweek.com/leadership/article/22...

https://www.bloomberg.com/news/videos/2019-09-05/a... from about 2 minutes on

This one makes the point that the FAA is saying they have fixed the faults on MCAS, but all the other things which have come out since are not being addressed.

https://www.aviationpros.com/aircraft/commercial-a...

Reading the FAA document, I'm pretty sure that it says the MCAS only once action is reset once the AoA goes below some magic number. So if the AoA fluctuates about that number you could still get multiple actions of the stab (I think), though there may also be some sort of max deflection in total check.

All in all to not have a way to shut the system off from action and still be able to manually or as a separate system trim the stabiliser doesn't seem right to me. But what do I know?

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Perhaps an alternative solution, and opportunity, is to sell the max's to a third party re-manufacturer, who would modify the planes as required by all intl regulators, and rebrand them and then sell them to the airlines.They would need to be sold at a discount, determined by the market. Adding 2 more AoA sensors and adjusting the MCAS gain inversely by the square of the airspeed plus wiring changes etc would be included in the rebranding. The reason Boeing won't do this is likely becuase it would be an admission of negligence in the initial design process, and that legal issue dissapears in the rebranding.

The third party remanufacturer could be an LLc, formed of a conglomerate of various airline mfr's, such as boeing , airbus, China's CAC, and other partners.By spreading the reponsibility, it ensures intl regulator acceptance and also airline company acceptance.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

You know just as much as the rest of us.

Common sense is being over ruled by interpretation and twisting of wording and fiddling of probability stats.

I suspect we will be still discussing what's going on this time next year.

I suspect the only way they will get everyone happy is by fitting smart probes which also measure AoA. But then they will be banging there heads against it not being a common type with the NG's

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Let's step back and look at the overall picture.
I am not sure of the correct terms so feel free to correct my terms.
Is it time for the regulators to address changes in stability resulting from engine offset from the center of gravity?
As one suggestion, but not the only one, what would be the effect of limiting the effect or authority of the stabilizer to a value that may be overcome by manual trimming at maximum forces?
I am dismayed by my understanding of the FAA ruling that the excess manual trim forces are OK because there is no regulation as to the maximum force allowable.
We have started to discuss the possible effect of the failure of MCAS to operate when it is needed.
Now how about the unavailability of manual trim when it is needed.
Come on FAA.
If there is no regulation, that is not an excuse. It is another instance of mission failure and a wake-up call to develop a reasonable regulation, without regard to the effect on the MAX.
I wonder if those already mostly completed MAX craft can be absorbed into the freight haul market?
They are efficient and they will probably be cheap.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

A question for the aviation experts.
With engine thrust tending to push the nose up, and the stabilizer trying to hold the nose down, is this causing a noticeable increase in fuel consumption, compared to an engine position that does not cause an uplift force?
I am not advocating that engine position, I am trying to find out how much increase fuel consumption is caused by a large engine displacement.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (FAA)

As instructed, the Ethiopian pilots hit the cutoff switches that killed power to the horizontal tail, stopping its movement. But then they found they couldn’t physically move the tail to a nose-up position by rotating a manual wheel in the cockpit.

Quote (FAA)

The FAA said that “simulator predictions validated by Boeing flight testing” were used to calculate the required trim wheel forces and that a mockup of the manual wheel demonstrated that with these procedures it could be moved even by smaller crews with less physical strength.
?????
I am sure that Boeing and the FAA can reconcile these statements.
However can that be done without setting off every BS detector within range?
Please explain what changes were made to the manual system so that at maximum stabilizer runaway at maximum speed, the manual trim wheel may now be moved by even smaller crew members.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The more the trim stab is pushing down the more fuel is burnt. The moment off the engine decreases the amount of trim stab required if it is forward and lower than the CoG.

We try and organise the load so that the CoG is towards the rear of the envelope to minimise it during cruise.

But you do get a noticeable difference in fuel burn. The fuel plan includes 3-5% extra to account for it.

Turning an aircraft into a freighter is a major mod. A big door has to go in, fire system and floor strengthened.

Personally I think they should go back to the NG and have one switch to kill the automatics but leave the electric trim working via thumb switch. And another to completely kill the power to electric trim.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Thank you Alistair.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

looking at the MAX orders it looks like they have already made the ones required for the USA Market. About 800 are required.

I believe they have over 500 in stock parked up.

The major orders from US operators are Air southwest, United, AA and Alaskan. The last one has issues because it will need to fly through Canadian airspace.

By far the largest orders are from leasing firms which usually require the aircraft to be able to go anywhere in the world.

I have been thinking along the same lines as the last few posts.

If MCAS is critical and required then there is very little safe guards to prevent you ending up without it. I presume the crew can turn it off just by killing one of the flight control computers.

If its deemed not critical flight envelope protection then you don't need it anyway.

I suppose it all centres around what alpha it actually starts kicking in anyway. Its turned off anyway when the flaps are out. So its not active during approach and only really comes on during 4th segment of climb after TO. Which only really leaves windshear and various escape procedures although windshear you would expect some level of flap to have been put out when you get it.

With that in mind and the relative ease now it gets turned off what's the point of having it anyway? There is a reg on control forces but if the system to control then gets killed when virtually any downgrade occurs then its pretty pointless.

To add the minimum equipment list is going to be interesting. There are going to be a whole heap of items not on it which on the NG you could go flying because they were listed which now have to be functioning because it kills the MCAS system. The NG has a great dispatch record with this key system requiring pretty much everything functioning thats going to suffer

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

seems there is a heap of poo about the FAA going on.

Must admit I have been taking that as a second political issue apart from the regulation side of things

Seems its the same issue as NASA with challenger. Again lesson not learned and loads of lives lost

https://www.seattletimes.com/business/boeing-aeros...

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

From the news:

It’s been approximately 12 million years since most of us last used a floppy disk, but apparently, the antiquated tech still plays a critical role in delivering software updates to Boeing’s 747-400 planes.

The discovery comes courtesy of cybersecurity firm Pen Test Partners and was initially spotted by The Register. As part of this year’s virtual DEF CON hacker conference, Pen Test Partners showed off a video walkthrough of a British Airways 747 after the airline decided to retire its entire fleet last month due to the global pandemic. The roughly 10-minute tour is a neat glimpse into the plane’s rarely seen avionics bay and cockpit—where Pen Test Partners discovered a 3.5-inch floppy disk drive.

Dik

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Sure, wouldn't surprise me a bit to see one on one of the CNC machines where I work. I wouldn't be too surprised to see one or a comparable magnetic media device on an F-22.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Magnetic media is surprisingly reliable. It doesn't degrade the way optical media like CDs do, and has a much longer life when unpowered than Flash (which loses its state slowly with time).

Also, the 747 is an old aircraft. Why change something that you don't need to, that provides no safety benefit from upgrading?

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Also it's been said earlier in the threads here that the FCCs are based on ancient technology so can't handle large amounts of data.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

remember when PCs came even without a hard disk? You needed your own floppy boot disk with an OS to even use the PC. I wonder if the the 747 captains have their personal boot disk in their flight bags in order to get the A/C to an operational state? ponder

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

The 3 1/2" floppies are still available on Amazon. Many are noted as "Discontinued by the Manufacturer".
Does anyone remember the 8" floppies? They were often referred to as "Mass memory".
There were a lot of formats but I understand that they maxed out at 1.2 MB.
There were a number of news reports last October:

Quote (ars Technica)

Air Force finally retires 8-inch floppies from missile launch control system
"Solid state storage" replaces IBM Series/1's floppy drive.
Sean Gallagher - 10/18/2019, 8:37 AM
The 3 1/2" floppies were modern technology by comparison.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

I still have one 8" floppy for posterity, but not the drive. I recall our PDP-10 minicomputer at work had a such a floppy for hard reboots. Note that it was only for the boot loader program; the OS resided on the hard drive, but at the time, there was apparently no way to get it to boot directly off the HD.

Obviously, that clearly solved by the time HDs were standard equipment on PCs.

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: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

There is a whole raft of old tech out there that uses various obsolete OS's and ports to interface with various bits of kit.

Some of it is OEM's going out of business, some of it is people trying not to have to pay the cost for the new software.

Also by changing the data input method you then trigger a recertification process.

Most of the new stuff uses flash memory cards and can be accessed from the flight deck in the maint panel. And you can update everything from there including the FEDEC's in the engines.

There has been a few times in the last 18 years that there has been a huge panic because the RS232 serial cable is broken or the windows 3.11 laptop has gone down.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

My first floppy 5-1/4 inch had 180k capacity and in 1981 that was a pretty hefty lift. Processor had 28k, also considerably high for its time.

I'm thinking this website needs a feature to load threads from last post at top to first post last at bottom. My screen protector is getting worn and ragged on the right side now.

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

If you manage to be able to click on thee "new" label it takes you to the new threads

Also at the top of the thread there is a "read new threads" button. Saves your thumb action

But that's why this thread is now at part VII

Need a part VIII sparweb? we're at 282 replies and we ain't done yet on this one I think.

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

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

ax1e, if you click on the "new" icon next to the the topic title, you will be taken straight to the first new post since your last visit. Once you have entered a thread you can also click on "read new posts".

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

My recollection is that my first computer, as well as the Osborne One, one of the first "portable" computers, had around 80k or 90k capacities. You pretty much had to have two drives because you needed one for the application itself, and the other to store data from the application.

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: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Quote (My first floppy 5-1/4 inch had 180k capacity and in 1981 that was a pretty hefty lift)


My first 2D Frame program, I wrote, swapped to those floppies and ran in 16K RAM... They were about $30 per box of 10 while the 360K diskettes were about $50.

Dik

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

New and read new posts only work if there have been new posts posted. If I want to simply add another post to a slow thread, its scrooling time again.

It was a Heathkit H89 - assembled myself, with all the goodies list.
Cost appx $3000 in 1981, which was about the same as my new Jeep J-10 pickup.
https://oldcomputers.net/heathkit-h89.html

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

the other issue is when you looking at it on a device you only want to view on and not login.

Its easy when your in front of a sit down computer dealing with it. Mobile devices its somewhat of a challenge depending what the layout its decided to use.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

Yup, no 'end' key on a mobile.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

But there is a "Reply To This Thread" button that takes you straight to the end of the thread.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

That only works works whe your logged in. Personally on company IT gear I never log in with personal accounts.

Ipad its not so bad on but phones its a whole load of finger flicking.

RE: Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7]

(OP)

Quote (ax1e)

...its scrolling time again.

Sure. I can split the thread.
Bear in mind that some of you guys are talking about Osborne portable computers this week so what's really adding to the post count, eh?

www.sparweb.ca

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