Earlier quoted context omitted.
Their logic was that pilots are trained to deal with runaway trim, a MCAS failure is runaway trim, ergo pilots are trained to deal with a MCAS failure. Obviously that logic turned out to be faulty but it's not like Boeing made some outlandish leap here.
You're right. Boeing did not make an outlandish leap of logic, or any leap of logic at all in this context, because it was fully their intent to get away with no training. They worked their butts off to minimize the training, to minimize even the very idea that training was needed, and to prevent the Max from having to be re-certified by the FAA.
Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
271–280 of 317 posts
Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#272Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#273Earlier quoted context omitted.
Specifically it's the argument in the article that large disasters often have multiple causes. "Perrow says, Murphy's Law is wrong—what can go wrong usually goes right. But then one day a few of the bad little choices come together, and circumstances take an airplane down. Who, then, is really to blame?" But that's exactly what's disingenuous about the GP's claim. Many disasters do indeed involve a sequence of mistak…
>But that's exactly what's disingenuous about the GP's claim. Many disasters do indeed involve a sequence of mistakes of different sorts but that's not really the case here. The situation with 737 max was one terribly system and the pilot's complete inability to stop this - inability that could have been anticipated and which was the product of the original bad design. MCAS is a badly designed system, but many other…
ET302 tried this-- maybe slightly late, but MCAS is weird/sneaky. Still, it's hard to fault their response at this point.
They were unable to budge the trim wheel because of overspeed. They were barely climbing at Vmo. This left them in a difficult position.
Ideal response would be to reduce power (prevent overspeed), keep climbing at Vmo. During this, try to turn trim wheel. If necessary, once they had sufficient altitude, they could aerodynamically unload and trim. Instead they, for some reason, decided to turn the stabilator trim system back on (whoops 1), and then used it an insufficient amount to get trim to a reasonable place (whoops 2), and then left it on for MCAS to trigger again (whoops 3).
Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#274Earlier quoted context omitted.
I strongly disagree with this one being a real link in the chain. OK, we put bigger engines on. The 737 is kinda already sporty and easy to get the nose too high on departure. Now it's a little worse with bigger engines. This is part and parcel for what happens when you stretch planes, adapt new engines, etc; there are minor, associated design changes you need to make to improve handling, etc. Software is a reasonabl…
You seem quite knowledgeable. You disagree with the statement that roughly the urge to avoid recertifying pilots caused Boeing to not mention MCAS even in manuals, leading directly to these deaths? Because from my pov, Boeing introduced a new failure mode (MCAS failure leading to intermittent forcing of the nose down) without any warning to the pilots. Now maybe the pilots' standard training should have compensated,…
I think there were failures across the board. The fundamental analysis of MCAS was flawed: it was much less reliable than was thought, and failures of it provided a much more difficult situation for pilots than anticipated.
I suspect the analysis boiled down to "MCAS provides a little defense against getting the nose excessively high on departure; it shouldn't be necessary so no big deal if it fails. And the worst failure we can think of is like stabilator trim runaway, which everyone knows how to deal with."
This was compounded by the fact that many developing countries do not require pilots to demonstrate they can deal with runaway trim as part of a checkride and recurring training.
Not disclosing information about the system made the problem even worse-- and this is harder to attribute purely to being part of bad initial analysis.
I do not understand some of the aircrew actions, even in retrospect. If I am fighting pulling the yoke back-- I am going to have my finger on the trim switch to try and get rid of those control forces, even before I am thinking about the problem. This would have inhibited MCAS and retrimmed the plane. I think that Boeing assumed that this would happen. I am lazy and would rather not have to tug the yoke so I use trim a lot. :P
Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#275Earlier quoted context omitted.
Out of the six points you mentioned, you blamed everyone, blaming the pilots twice, and merely mentioned this against Boeing: > The flight computer system and MCAS was implemented problematically, relying on one input because the expected control authority was very low, and then when that was not changed the system was not re-architected. Do you have a personal stake in Boeing or something? Because you appear very bi…
Every time we blame a crash on pilots, we are blaming it on training. Aside from some truly exceptional cases,* pilots who contribute to a crash are having issues because they have not been trained adequately in dealing with the situation. I believe that these two crashes indicate there is a need for reinforcement of the CRM training and also more training on unexpected situations. We can try to blame Boeing for the…
My point is, there are a lot of technical and ethical oversights you are glossing over. There is a reason why all the 737 Max are grounded and have been grounded for months. These crashes weren't simply due to lack of pilot training. There were multiple ethical and technical oversights and negligence by Boeing that resulted in these tragedies.
Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#276Earlier quoted context omitted.
Also all of the US-based MAXs had the optional AoA Sensor Disagree indicator, which would instantly show the source of the issue. The international pilots were in the dark because Boeing turned a critical safety feature into a revenue stream.
AoA Disagree was supposed to be turned on on all 737 MAXs, but it depended on AoA indication, which was an option. This was a mistake Boeing admitted to and has since corrected. Options are not all tied to fees, the process of ordering an airplane is quite complicated because of the immense amount of customization each airline does before they even pay for the aircraft. Its unclear how much this option cost, if it co…
Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#277Earlier quoted context omitted.
The general idea was that pilots would correctly recognize large amounts of undesired and uncommanded trim being runaway trim and perform the checklist to resolve that issue that they are expected to know by memory, since there is a need to execute it fast, without paging through the Quick Reference Handbook. This is not a checklist that was introduced with the 737 MAX, but one that has existed since the introduction…
3. Who had a simulator that simulated MCAS upset? 4. Which is not at all what happens with runaway trim. Also runaway trim that pilots are trained on is a consistent and relatively slow trim. The MCAS upset form is intermittant, and can be but isn't always, aggressive and comes with a ton of other data in the form of various instrumentation disagree warnings and possibly stick shaker going off which NEVER happens in…
The reason that '427 pilots aren't blamed is that it's unclear that with perfect inputs that the plane was recoverable. We also excuse them a bit because the situation became unrecoverable in a matter of seconds since it manifested, instead of a longer time with the MCAS upsets.
Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#278Earlier quoted context omitted.
> "Boeing's designs reflect a US-centric expectation of pilots" So we are expected to believe that Boeing never connected the dots between: 1. We design planes for US pilots 2. We sell planes abroad 3. Incidents abroad can ground an entire aircraft series This makes them seem more incompetent, not less. It's not like they have no say in what's considered standardized training for the series.
It's an appeal to "intelligence of operator" to coverup for poor design.
Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#279Earlier quoted context omitted.
You seem quite knowledgeable. You disagree with the statement that roughly the urge to avoid recertifying pilots caused Boeing to not mention MCAS even in manuals, leading directly to these deaths? Because from my pov, Boeing introduced a new failure mode (MCAS failure leading to intermittent forcing of the nose down) without any warning to the pilots. Now maybe the pilots' standard training should have compensated,…
I disagree that deciding to stretch the 737 is fundamentally bad engineering. Yes, it realistically requires some control augmentation (and maybe earlier 737's should really have had something like MCAS, too). Yes, bigger engines and heavier 737's have the problem worse, but it isn't unreasonable to fix this with systems. I think there were failures across the board. The fundamental analysis of MCAS was flawed: it wa…
It's building in a new control system and not telling the pilots about it that seems crazy to me.
Thanks so much for your thoughts!
Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes
#280This seems like a good thing, they should be testing with people who don’t know the answers. Though I can’t help but wonder if this is a very subtle re-framing of the Max accidents to shift blame back towards pilots. This approach of a regulatory agency recommending “average pilot” testing makes both the agency and Boeing look good, and tends to downplay the fact that Boeing intentionally avoided training the pilots,…
The boeing model, apart from MCAS, has traditionally been "the pilot decides"
Would this shift towards the airbus model (the plane decides)?