Don't fly on a 737-MAX

Timcito

darthed1981 said:
The problem is that there is ultimately nobody in power in a big business whose main job is being moral.  

That does not mean companies don't take safety seriously. Morality or no morality, when people get hurt or killed, it costs millions in lawsuits.

Musical_Mystery_Tour

Looking at what information there is thus far, it appears there was an issue with the fitment and adjusting of the door in terms of the door stop lugs on the door and those lugs on the surrounding fuselage not being lined up properly before it was sealed off with interior trim.

This is a rigging job when the door is fitted to ensure these lugs are properly aligned when the door is in the shut position. There is a mechanism at the bottom of the door which allows it to move down so the door lugs can clear the doorframe lugs and then move in and then pivot outwards. That alignment of the lugs has to be set correctly; if it is, there should be no way the door can actualy blow out since the pressure is normally pushing it against the lugs and even when the cabin is not pressurised, being a plug door, it still has to move inwards and downwards initially before it can be swung open.

Anyone who has ever opened or closed an airliner door will tell you that they are pretty heavy and it takes a lot to move them. Whenever I am removing the steps from an airliner, I usually help the cabin crew to swing the door in because of how much they weigh and how much effort it takes to get them moving. When you see the door go in slightly past the fuselage skin, and then move vertically before coming out a little to sit flush, that's the door going past the lugs in the door frame and then moving to sit behind them to prevent them actually from being able to blow out.

Since there has been a widespread grounding of the type, and such factory work as rigging the doors is a task which has to be signed off, it would appear they have traced the cause to probably a few certain workers who may have not been doing their job properly thus they want to inspect all the doors those certain people may have worked on and signed off on as being properly fitted and rigged.

It's very lucky that nobody was sat in the window seat next to that door when it blew out, because if there was and they had not been wearing a seatbelt, it's likely they would have been blown out by the air pressure as the cabin depressurised. Apparently a few people nearby lost some items of clothing and stuff they were holding such as mobile phones etc, when the door blew. It's also luck tht the door didn't hit the horizontal stabiliser as it departed. It's one of the reasons why I never take my seatbelt off when seated and flying on an airliner, turbulelnce being the other.

ICBM

Grangousier said:

Talking to my wife about this earlier - it's something she pays a lot more attention to than me - she said that basically McDonnell-Douglas was destroyed by its accounting division cutting everything in pursuit of more profits, then when Boeing bought them the same people went on to do the same thing to them. Is that the case? It satisfies my anti-corporate, anti-financialised capitalism bias so I may choose to believe it anyway. 

From reading various American aircraft forums, I think that is the case. It doesn't surprise me at all, because the same thing happened in the UK, when Lloyds Banking Group (which MrsICBM works for) bought out/rescued HBOS after the 2008 crash. Despite being the failing company, it was HBOS management practices which were then imposed on the whole group. I cannot fathom why it should have been allowed to happen in either case.

I also think the decision by Boeing to move its headquarters away from Seattle is a major part of the problem, as well as the contracting-out of sub-assemblies. Sadly, unless something very major is turned around and the company culture put back to something like how it was 30 years ago, I don't think Boeing has a good outlook.

Chalky

Kittyfrisk said:

Not claiming particular relevance but I found this interesting  https://www.bbc.co.uk/news/world-africa-47553174

A contributing factor to the Lion crash was that the engine power was left at very high levels, as if the pilots were both trying to solve the pitching problem instead of one solving the problem while the other managed other flight aspects such as engine power and speed.  Manual trimming made far more difficult by high speed.

Tannin

ICBM said:

 Sadly, unless something very major is turned around and the company culture put back to something like how it was 30 years ago, I don't think Boeing has a good outlook.

If they were a normal commercial business in a competitive market, I'd agree with you.  If this was 30 years ago, Douglas and Lockheed would trample them into the dust. 

But now there is only Boeing. No other company makes large commercial  airplanes (sic). (Foreign companies don't count. Not in the USA.) More to the point, the US relies absolutely on Boeing for the majority of its military aircraft. The company simply cannot and will not be allowed to fail. The US will spend whatever it takes to prop them up, and/or hand them massive sweetheart deals on their military contracts (not for the first time!), and/or figure out ways of banning or taxing competing products (primarily Airbus).

Boeing will survive. I don't reckon they'll be paying useful dividends for a very long time, and it very much looks as though we are going to see the world aviation market share split blow out to something close to 70/30 in Airbus' favour, but Boeing will still be here in 20 years time. 

Hell, by then the Chinese might have finally figured out how to make a competitive commercial aeroplane. 

Boeing as a company used to take some very brave decisions. They were wiling to bet the company on the main chance, and it paid off for them in spades. The old Boeing would have gone for broke with an all-new 737 replacement and now we'd all be talking about how shaky Airbus looked. But those days are long gone.

Danny1969

I find the whole thing bizarre.  It wasn't a door, it was a door plug which is hinged on the bottom but mouse eared on the sides into indents to stop it ever blowing out. So something gave way 

Also the auto depressurisation fail light has illuminated on 3 separate occasions prior to this event    .   Dec 7th, Jan 3rd and Jan 4th but they never really investigated why, just switched to the alt backup.  Later they just tested  it and basically said not sure what the issue is but lets not let it fly over the ocean as it seems a bit iffy.     

I get planes have redundancy but whole point of redundancy is that it is there when you need it. You can't say oh the normal mode of depressurisation detection is faulty we will use the alt mode .... that's now basically flying without the redundancy.  

They knew the plane was faulty because they ETOP's it ... not letting it go far from an airport. 

Deadman

This is quite informative:

https://www.reuters.com/business/aerospace-defense/spirit-aero-made-blowout-part-boeing-has-key-role-sources-2024-01-07/

Gassage

Musical_Mystery_Tour said:

It's very lucky that nobody was sat in the window seat next to that door when it blew out, because if there was and they had not been wearing a seatbelt, it's likely they would have been blown out by the air pressure as the cabin depressurised. 

Not a hope- At 16,000 ft the cabin differential surely wouldn’t be more than say 5psi. 

m_c

Gassage said:

Musical_Mystery_Tour said:

It's very lucky that nobody was sat in the window seat next to that door when it blew out, because if there was and they had not been wearing a seatbelt, it's likely they would have been blown out by the air pressure as the cabin depressurised. 

Not a hope- At 16,000 ft the cabin differential surely wouldn’t be more than say 5psi. 

I wouldn't be so sure.
It was maybe only 5psi differential, but there would be a lot of air volume involved, and when you consider the force on the door alone was in the region of 13'000lb, a body could quite easily be blown out in the force.

And it's just made me check the BA flight where the pilot got sucked out. It was apparently at 17'300 feet, when the window failed.


And then the NTSB has given their initial briefing.
Flight deck door blew open. Co-pilots headset was removed. Pilot almost lost his. Quick Reference checklist was also removed.
They're also not happy that the CVR has been overwritten as nobody pulled the circuit breaker.


Big thing for me is the US's reluctance to use Mayday.
The comms with ATC are horrendous, with the Co-pilot even asking for permission to descend at one point, and ATC asking more than once what the emergency was.

drofluf

m_c said:

Gassage said:

Musical_Mystery_Tour said:

It's very lucky that nobody was sat in the window seat next to that door when it blew out, because if there was and they had not been wearing a seatbelt, it's likely they would have been blown out by the air pressure as the cabin depressurised. 

Not a hope- At 16,000 ft the cabin differential surely wouldn’t be more than say 5psi. 

I wouldn't be so sure.
It was maybe only 5psi differential, but there would be a lot of air volume involved, and when you consider the force on the door alone was in the region of 13'000lb, a body could quite easily be blown out in the force.

Plus you have the Venturi effect through the doorway - think how much things get blown around if you lower the car window at 70mph and bear in mind the plane was probably doing at least 3 times that speed. 

Musical_Mystery_Tour

Gassage said:

Musical_Mystery_Tour said:

It's very lucky that nobody was sat in the window seat next to that door when it blew out, because if there was and they had not been wearing a seatbelt, it's likely they would have been blown out by the air pressure as the cabin depressurised. 

Not a hope- At 16,000 ft the cabin differential surely wouldn’t be more than say 5psi. 

It was enough of a pressure difference to make a heavy door blow past the stop lugs and detach from the aeroplane, yank people's phones out of their hands and tear bits off the seats on that row. I'm pretty sure anyone sat in the window seat with no seatbelt on  when it blew, would have been going skydiving.

For reference, most airliner emergency doors weigh at least 25 kilogrammes; main doors weigh about 100 kilogrammes.

Kurtis

I've not flown in anything for years and expect I never will again. 

darthed1981

Kurtis said:

I've not flown in anything for years and expect I never will again. 

Given average Fretboarder age I'm guessing... a Lancaster?

ICBM

Danny1969 said:

I find the whole thing bizarre.  It wasn't a door, it was a door plug which is hinged on the bottom but mouse eared on the sides into indents to stop it ever blowing out. So something gave way

I don’t think so - apparently the plug does open outwards, once it’s lifted up far enough to clear the stops. It looks like whatever bolts are supposed to hold it in the safe position were either never fitted, or loose and worked their way out, then allowing the plug to creep upwards until it was past the stops - which would explain why it finally blew out at only 16,000ft, despite having been to at least 39,000ft over a hundred times previously.

But they've found the door now, so presumably that can be determined conclusively.

m_c said:

They're also not happy that the CVR has been overwritten as nobody pulled the circuit breaker.

2hrs before overwrite is ridiculous for a modern digital CVR - it goes back to the days of it being a tape loop. Memory is so compact now that it could easily store weeks of simple audio.

drofluf

ICBM said:

They're also not happy that the CVR has been overwritten as nobody pulled the circuit breaker.

2hrs before overwrite is ridiculous for a modern digital CVR - it goes back to the days of it being a tape loop. Memory is so compact now that it could easily store weeks of simple audio.

I agree but whilst the fix is simple it would either be a new type of recorder or an upgrade both of which would need to be tested to ensure they didn’t interfere with the other systems. And that testing comes with a cost…

darthed1981

ICBM said:

2hrs before overwrite is ridiculous for a modern digital CVR - it goes back to the days of it being a tape loop. Memory is so compact now that it could easily store weeks of simple audio.

Given as it's in a 737-Max, I guess Boeing figured they could pad it out with stock air crash noises if needed.

Kurtis

darthed1981 said:

Kurtis said:

I've not flown in anything for years and expect I never will again. 

Given average Fretboarder age I'm guessing... a Lancaster?

A blimp. 

darthed1981

Kurtis said:

darthed1981 said:

Kurtis said:

I've not flown in anything for years and expect I never will again. 

Given average Fretboarder age I'm guessing... a Lancaster?

A blimp. 

Ahhh....



<note to pedants - yes I know it's a dirigible - also genuinely staggering footage to this day>

menamestom

Tannin said:

ICBM said:

 Sadly, unless something very major is turned around and the company culture put back to something like how it was 30 years ago, I don't think Boeing has a good outlook.

If they were a normal commercial business in a competitive market, I'd agree with you.  If this was 30 years ago, Douglas and Lockheed would trample them into the dust. 

But now there is only Boeing. No other company makes large commercial  airplanes (sic). (Foreign companies don't count. Not in the USA.) More to the point, the US relies absolutely on Boeing for the majority of its military aircraft. The company simply cannot and will not be allowed to fail. The US will spend whatever it takes to prop them up, and/or hand them massive sweetheart deals on their military contracts (not for the first time!), and/or figure out ways of banning or taxing competing products (primarily Airbus).

Delta and American Airlines, the 2 biggest airlines in the US are pretty much 50/50 Airbus/Boeing, so I wouldn't say they don't count.  Southwest are all Boeing, United mainly Boeing, but they have Airbus and more on order.

Military, I thought that Lockheed Martin would be the main supplier nowadays?  They make the F-35, which is replacing the now phased out F-18 (out of new orders, not service).  That said, LM subcontract some manufacture to Boeing so this is not to say they are not intrinsically linked.

You're probably right that they won't be allowed to fail, but even in the US, the reliance on Boeng doesn't seem to be quite so absolute.

Danny1969

ICBM said:

Danny1969 said:

I find the whole thing bizarre.  It wasn't a door, it was a door plug which is hinged on the bottom but mouse eared on the sides into indents to stop it ever blowing out. So something gave way

I don’t think so - apparently the plug does open outwards, once it’s lifted up far enough to clear the stops. It looks like whatever bolts are supposed to hold it in the safe position were either never fitted, or loose and worked their way out, then allowing the plug to creep upwards until it was past the stops - which would explain why it finally blew out at only 16,000ft, despite having been to at least 39,000ft over a hundred times previously.

But they've found the door now, so presumably that can be determined conclusively.

Ah yes, here's a diagram