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Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

bbc.co.uk

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Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#271

Earlier quoted context omitted.

There was definitely an air of superiority of American pilots. The problem is that there is a grain of truth to it. A big part of this is that the American Airforce train a huge number of pilots to an incredibly high standard who eventually leave the military and become civilian pilots. Any pilot who isn't naturally gifted in the art of flying an aeroplane will be flunked before finishing their training. They are tes…

So, do you know as a fact that plots in other countries are less passionate or have less training? It would be interesting if you have a source of how many civilian pilots are ex-military pilots, as an non-expert I would say that having experience with a fighter plane is not better then having same hours of experience with a civilian plane, it is not like fighter plane experience is much better then other planes when…

So, do you know as a fact that plots in other countries are less passionate or have less training?

Option C: crew resource management and by extension culture. Take a look at one of (if not the) worst aviation wrecks in history: the Tenerife disaster. A Dutch 747 (KLM) and American 747 (PanAm) collided and became engulfed in a gigantic fireball. The biggest factor was that nobody was willing to speak up or acknowledge in either cockpit that there was uncertainty and an unsafe situation. Yes these are two western countries, but after the wreck western aviation culture changed dramatically as a significant emphasis was put on what amounts to "see something? say something!!" (a.k.a. crew resource management, CRM).

CRM has been very slow to trickle down to, for instance, East Asian airlines where deference to authority has a much stronger hold. Take a look at the Asiana wreck at SFO. Two pilots in the cockpit were repeatedly calling out significant mistakes, but the pilot flying ignored them. Neither of the other pilots took control of the situation and the plane was flown straight into the ground.

Training, as well, seems to be something American pilots are pretty prickly about. After a Continental regional airline (Colgan Air) wrecked the solution was deemed to be requiring more pilot training (despite the fact that experience was NOT the problem in this crash). For all the belly aching about the guy in the left set of the Ethiopian Air jet having only a few hundred hours — up until 2013 the FAA only required 250 hours of experience to get a certificate allowing commercial flight (ATP). The requirement now is 1,500 hours, but it sure doesn't seem like American air travel has become dramatically safer since 2013.

I don't think passion is the right word, but the USA has a much stronger general aviation culture than many other counties. Someone living in America is going to have many more opportunities to fly a civilian plane than someone living in, for instance, South Korea. The military experience may even be detrimental as it's often going to focus on strict hierarchies (see CRM) when this may create safety problems.

Edit: I want to add that Indonesian aviation is notoriously unsafe and most Indonesian airlines have been banned from EU airspace (with some allowed back more recently). Lion Air, in particular, has a bad record of wrecking planes and lots of allegations about falsifying maintenance records. Hell, there is that one Lion Air captain who posts cockpit videos on youtube (including at least one showing some startlingly sloppy behavior). But if you look at flight 610 specifically you'll start to see a lot of things that would put even the best pilots in a bad situation. Even looking at the data from flightaware should've provoked a bit of an "are these pilots REALLY that bad?" response. A certain amount of initial suspicion was warranted, especially since pilot error is an extremely common cause of crashes even in western countries. A more continued drive to vilify the JT610 pilots or excuse Boeing's behavior is, IMO, out of line.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#272

Earlier quoted context omitted.

So, do you know as a fact that plots in other countries are less passionate or have less training? It would be interesting if you have a source of how many civilian pilots are ex-military pilots, as an non-expert I would say that having experience with a fighter plane is not better then having same hours of experience with a civilian plane, it is not like fighter plane experience is much better then other planes when…

Apparently somewhere around 30% if this is to be believed. https://www.washingtonpost.com/news/wonk/wp/2018/04/20/the-o... "A grain of truth" doesn't mean it's provably true. But it's hard to argue that flying a plane load of passengers on autopilot from the same 4 airports for hours on end remotely gives you the same skill level as flying low level, in high performance and often in formation with other aircraft woul…

But it's hard to argue that flying a plane load of passengers on autopilot from the same 4 airports for hours on end remotely gives you the same skill level as flying low level, in high performance and often in formation with other aircraft would.

Fine, I'll argue that. Southwest pilots do just that because Southwest is primarily a short haul airline. They do more takeoffs and landings on a daily basis than nearly any other airline and often from relatively small airports. If you're flying for them you're going to routinely practice the most dangerous parts of the flight. IIRC Southwest is less draconian about mandating autopilot usage than many other airlines.

They have a reputation for being aggressive about timing (as my friend put it, you never want to be stuck in front of a Southwest pilot) and yet they have an enviable safety record.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#273
post #265

Earlier quoted context omitted.

The problem is that you can easily exceed the aircraft flight specifications if you enable unlimited control. If you pull the stick back at max power you can seriously risk the creation of a stall, which is why MCAS exists in the first place. That's manifestly wrong. MCAS was introduced because of the design decision to place the larger and more powerfull power plants further in front and higher up. The reason for th…

>MCAS was introduced in order to simulate the same behavioral characteristics of the older 737s. Sounds plausible, but something with the story is still super screwy because a nose down "push" every 15 seconds is nothing like older 737 approach to stall behavior. If the idea is you want the same stick forces at approach to stall as 737NG, then you need some kind of motor or brake in the yoke mechanics to simulate it…

But something stinks. I don't see how it gets around either FAR 25 airworthiness certification requirements, because it can be disabled.

That's easy. When the manufacturer rubberstamps his own ariworthyness certification this is not really a problem.

Disable it, and now your airplane is not airworthy and your pilot possibly not suitably type rated?

That's the exact crux of the issue. Boeing panically wanted to avoid recertification of the plane and the pilots in order to be competitive with Airbus' A320 NEO.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#274
post #152

Earlier quoted context omitted.

FAA defended 737 Max to the very last minute, FAA is nothing else but a cheap tool for big corporations like Boeing.

The last minute when they grounded them? I don't recall them "defending" anything, anyway, they simply held off grounding them until they got a little bit of data to back it up.

> they simply held off grounding them until they got a little bit of data to back it up

In my dictionary I have the following term which FAA and Boeing both actively ignored/violated.

pre·cau·tion /prəˈkôSH(ə)n/ noun a measure taken in advance to prevent something dangerous, unpleasant, or inconvenient from happening.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#275
post #240

Earlier quoted context omitted.

It is hard to imagine how any 737 pilot would be unaware of the problem and resulting Boeing advice given the massive amount of attention this has reviewed. Regardless of training issues I find it hard to believe that any pilot would be so indifferent as to ignore this.

So you blame the pilot that he is not training itself in the new hidden changes of the airplane? Isn't Boeing duty to create the checklists/procedures for the possible issue ? or we let this work for the pilots internet forums? Though from the article it appears that pilots followed all the official procedures,

Of course it is Boeing and airlines responsibility. But if for some reason that training was absent I would expect pilot to seek the information themselves. To suggest otherwise is an insult to their intelligence and professionalism. Of course pilots are going to take an interest in crashes on the aeroplane they fly! Particularly when it is the biggest aviation story in years. Porbably something that they discuss regularly with other pilots. That is why I think the poor training angle is implausible for this particular issue and just prejudice.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#276

Earlier quoted context omitted.

Apparently somewhere around 30% if this is to be believed. https://www.washingtonpost.com/news/wonk/wp/2018/04/20/the-o... "A grain of truth" doesn't mean it's provably true. But it's hard to argue that flying a plane load of passengers on autopilot from the same 4 airports for hours on end remotely gives you the same skill level as flying low level, in high performance and often in formation with other aircraft woul…

But it's hard to argue that flying a plane load of passengers on autopilot from the same 4 airports for hours on end remotely gives you the same skill level as flying low level, in high performance and often in formation with other aircraft would. Fine, I'll argue that. Southwest pilots do just that because Southwest is primarily a short haul airline. They do more takeoffs and landings on a daily basis than nearly an…

Sure, but southwest already has US pilots, many of them ex-military, who have all of the advantages I've mentioned.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#277
post #165

Earlier quoted context omitted.

>the Lion Air crash (they were busy smearing the airline an the pilots instead) In a rush to put to blame on Boeing everyone seems to have forgotten that Lion Air badly screwed up: (1) The aircraft exhibited the same failure on its previous flight. Not fixing it before the next flight is a huge maintenance screw up. (2) That failure and the steps to correct it should have been in the log book and the next pilots shou…

As we have now learned, switching to the manual control is useless when the aircraft is in this condition (high speed, stab down, elevator up). The Ethiopian pilots turned off the electric trim control, only to have to turn it back on again.

Slight correction, they turned off the stab trim and tried to manually re-trim the plane, but the aerodynamic loading on the stabilizer was so great that they couldn't turn the trim wheel by hand. So, sadly, they re-engaged the stab trim and began to use the switches to trim up, but the MCAS came back 5 seconds later, trimmed down again, and flew them into the ground.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#278
post #224

Earlier quoted context omitted.

Agreed. After the Lion Air crash, Boeing basically asserted the plane was perfectly safe, and that the pilots should have followed the runaway trim process - this means turning off the electric motor which moves the trim, and having the pilots move it manually using a wheel provided for the purpose. Boeing has tried to imply that in the midst of an emergency which looks very different from a runaway trim, pilots shou…

There's a major difference between the Lion Air and Ethiopian Airlines crashes though - altitude and incident duration. Things that are recoverable from 5000' AGL might not be from 1000' AGL. Speed is life, and altitude is life insurance after all. From my reading, the Lion Air pilots could have disabled electronic trim anytime after those 26 recoveries and been fine. But the Ethiopian Airlines pilots only had 1000'…

The report is now available at https://www.documentcloud.org/documents/5793877-Preliminary-...

Flaps-up was commanded about a minute after take-off, which seems about right. The AGL altitude of the plane is hard to determine from the graphs as they only list pressure altitude. It's a high airport with, I believe, rising terrain. I'm not sure if the 1000' AGL cited is supposed to be at first MCAS engagement, or the last one, or at some other point in between.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#279

Earlier quoted context omitted.

The explanation put forward (which seems reasonable) is that the cutouts were disengaged because the aerodynamic forces were stronger than could be overcome by the manual control, so they had to turn the electrics back on in an attempt to move it (which allowed the MCAS to continue pushing the stabilizer to the extreme)

Ah. They'd have had to "roller coaster" the airplane (pitch up, then move the elevator surface towards neutral [so a net nose down]) to get the trim to move manually [the last step on the checklist]. Repeat as needed until the stab is trimmed within a range where it can move manually in unaccelerated flight. That's an interesting possibility, which if they didn't know about it (I don't blame them), they may have felt…

It's a shame that MCAS behavior wasn't fully explained after the first crash. If it had, they might have remembered that flaps disable MCAS. If I had to go "off checklist", I'd go: stab trim off -> flaps 1st detent -> stab trim on -> trim to neutral -> stab trim off for duration of flight -> flaps up -> manual flight for the duration. Still, that's all while you're pulling on the column like mad, all the indicators are lit, all the annunciations are going on, the stick shaker is going, you're going like a bat out of hell, and the ground is coming up at you. In the final seconds of flight, there was so much nose-down that they were pulling -2g.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#280

Earlier quoted context omitted.

The explanation put forward (which seems reasonable) is that the cutouts were disengaged because the aerodynamic forces were stronger than could be overcome by the manual control, so they had to turn the electrics back on in an attempt to move it (which allowed the MCAS to continue pushing the stabilizer to the extreme)

Ah. They'd have had to "roller coaster" the airplane (pitch up, then move the elevator surface towards neutral [so a net nose down]) to get the trim to move manually [the last step on the checklist]. Repeat as needed until the stab is trimmed within a range where it can move manually in unaccelerated flight. That's an interesting possibility, which if they didn't know about it (I don't blame them), they may have felt…

Another thing we know now about MCAS is that it's locked out for 5 seconds after each trim switch operation. So, if you never have stab trim engaged for longer than 5 seconds a shot, you should be able to trim up the plane.
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