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The ejection seats on the F-35 Joint Strike Fighters are faulty...

The ejection seats on the F-35 Joint Strike Fighters are faulty...

The ejection seats on the F-35 Joint Strike Fighters are faulty...

(OP)
It appears that the Martin-Baker ejection seats installed in F-35 Joint Strike Fighters have been found to be faulty. The 'cartridges', that when ignited, propels the pilot's seat out of the cockpit, were found to not contain the material needed to set off the charge, and they've known this for three months but have just now grounded the planes:

Most US F-35s temporarily grounded as ejection seat issue threatens jets worldwide

Air Force discovered defect in April but didn’t know its full scope


https://www.militarytimes.com/news/your-air-force/...

John R. Baker, P.E. (ret)
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: The ejection seats on the F-35 Joint Strike Fighters are faulty...

Has there been an airplane design that's easily ejected from?

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

This is a bit more serious than that. No bang to throw them out.

Kudos to the squibber that noticed the suspect weight.

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

It's curious that there was not an inspection system that would automatically reject a failed cartridge.

In this case, not only was there multiple failures to "fill", but also multiple failures to catch the fact and do a rejection. There should have been a failsafe inspection of every cartridge.

I am also surprised at the duration of this episode. Three months to determine IF this was an isolated incident? Nope. A week. Info blast to all concerned: check these parts and report immediately! Then a preliminary investigation for another week--we visit the production facility and let them explain how this happened and how it will be fixed and how it will never happen again.


spsalso

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

There was something similar loading up tanks to go to Gulf 2 on boats.

One of the crane operators queried why some of the tanks were 15-20 tons lighter than others.

Got told to mind his business by the young tankie officer. When he spotted a sgt wandering around went and told him.

All hell lets loose because the sgt immediately recognised that the light ones were training tanks not war tanks with full amour

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

Quote:

It's curious that there was not an inspection system that would automatically reject a failed cartridge.

These are one-time use cartridges.

We did something similar with a leaky gas bottle that had to be weighed, in-situ, to determine if it was still usable; 50-lb object missing about 0.5 grams

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: The ejection seats on the F-35 Joint Strike Fighters are faulty...

Are these sealed units? then, how would you test them? ponder

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

-Dik

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

Destructive test by some skip lot criteria.
Non destructive test for fill could be weight or X Ray on the production line.

Government specifications here usually have detailed requirements.

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

Thanks...

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

-Dik

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

If there's a weight issue, it seem rather easy to find...

I’ll see your silver lining and raise you two black clouds. - Protection Operations

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

My younger self shrugs while rolling into combat in unarmored ground vehicles.

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

Quote:

Are these sealed units? then, how would you test them

If the ignition charge is missing, then you could hypothetically weigh the canister and see if it's lighter than it's supposed to be. Alternately, you could possibly x-ray them

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: The ejection seats on the F-35 Joint Strike Fighters are faulty...

Yes.

You can do that.

Seems kind of obvious after the fact.


spsalso

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

" The military had tested 2,700 F-35 ejection seat cartridges and discovered three failures as of Wednesday,"
so a random/lot check could have missed it.

Jay Maechtlen
http://www.laserpubs.com/techcomm

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

What about military hardware was designed to be safe? The fact of an ejection seat just may be safer than not having one is a thing.

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

"...why some of the tanks were 15-20 tons lighter than others....All hell lets loose because the sgt immediately recognised that the light ones were training tanks not war tanks with full amour"


This has lingered in my mind, and remains hard to believe.

That 15-20 tons isn't (mostly) bolted on. It's integral to the design of the machine. You would have to redesign the whole structure to use radically thinner material. So you'd have a huge added expense, combined with making a tank that couldn't ever be used in warfare. If it WERE bolted on, it would be obvious that something was missing during a visual examination.

I would question how useful a training tank that was lightened that much would be. Maneuverability would be radically different.

If you want a training tank, have them take out one of those clapped-up items over there.....


spsalso


RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...


quote:

" The military had tested 2,700 F-35 ejection seat cartridges and discovered three failures as of Wednesday,"
so a random/lot check could have missed it.

/quote

These are not items that should be randomly checked. EVERY ONE should be checked. And SHOULD HAVE BEEN. There is no excuse for letting any of these through.

Note that the first discovery was by a guy who felt the item in his hand felt light. A simple scale would have found this.

I think the president of the company should make visits to the crews who use this equipment and make a personal apology for screwing up and endangering their lives.


spsalso

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

They are different apparently and don't have the reactive armour fitted. Just dumb boxes. Also they have training NBC kit.

They can fire and have the weapons systems and coms.

I think all the ones in Canada are also training fit.

Saves a fortune in fuel.


Combat fit is 75 tons
Training about 60 tons.


RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

The existence of a training tank would seem odd to me except its govt, and I saw nuttier things in the military. The hulls themselves are often aluminum with AR500 or similar bolted on, so the difference in weight armored vs non seems right to my mind having seen 2.5 tons added to older HMMWVs with homemade "boonie" armor. I also wouldn't doubt that the appearance could be similar, esp to junior officers who aren't always the brightest or most experienced.

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

Just had a thought

Reactive armour involves loads of explosives.

Explosives get stored in a secured area or magazine.

Training tanks which spend Thier time on a range would need security or a pretty large building. In real life they are parked up in a Nissan hanger with a padlock keeping people out.

Transporting them about is a major pain in the bum either by self drive or low loader.

If there is no ammunition or explosives involved life is much easier for everyone.

I suspect they can make them combat fit relatively quickly.

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

I remember as kids that there were tanks and howitzers at McGregor amouries across from our grade school. After school we used to play on them, and occasionally get 'chased off'. I suspect they were training tanks (didn't know there were two types)... not secured in any fashion... that was more than 60 years back, though.

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

-Dik

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

It was the same when I was in as long as there was no bang involved. Artillery guns just dropped in the MT car park.

As soon as there was it was either in a secured compound or guard.

There maybe wasn't a training tank 60 years ago until the reactive armour came along.

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

So apparently the training tanks had plywood boxes replacing the reactive armor for safety reasons during training. Makes a lot of sense, especially since you don't need it during training unless your "shooting buddy" gets real confused.

And, if you're bothering to replace the real thing with plywood boxes, you'd probably like it to look real, and so it could fool some onlookers. I am having trouble seeing why anyone would bother.

But I'm having trouble seeing the weight of reactive armor as being 15 to 20 tons. A quick lookup comes up with 3 tons.

What I do see is that Leopard 2's weigh around 70 tons. And Leopard 1's weigh about 40 tons. If there were some of the 1's retained for training, perhaps someone shipped them out with the 2's. That would (easily) account for the dramatic weight difference. But how such a thing could ever happen is.......

I think training tanks are old tanks no one wants, but are still useful to teach the newbs on. If someone did something fancier, I'd like to see some hard data on that.


spsalso

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

The NBC packs are hellish heavy lumps of machinery that need the turret lifted to fix/fit/remove. .

These are UK challanger tanks I am on about.

I never worked on them apart from splitting tracks.

https://en.wikipedia.org/wiki/Challenger_1

https://en.wikipedia.org/wiki/Challenger_2

Must have been a challanger 1 that heard about.

So call it 2 tons for the NBC and Aircon pack about 11 tons additional, They might have had a couple of barrels strapped to them as well. I really don't have a clue what you load in a combat fit MBT.







RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

I can see someone sending Challenger 1's without extra armor (that were being used for training) along with the 2's--a weight difference of 15 tons. And getting past a clueless officer. Or two.


spsalso

RE: The ejection seats on the F-35 Joint Strike Fighters are faulty...

"The ejection seats insert component here on the F-35 Joint Strike Fighters are faulty..." could apply to so many F35 headlines

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