[CorvusCrypto]

Yes I agree. And I'm pleading that everyone also recognise the other aspects of these.incidents such as improper basic procedure. It's all of the above.

Edit: And remember at the end of the day, these airlines and pilots agreed to fly the plane. Even in the wake of the LionAir incident. At the end of the day, the pilots choose to fly and can say no if they aren't comfortable. And if the answer to this is that there is pressure from airlines to keep flying? We just found another major issue and danger in aviation

Edit2: should clarify actually that I agree it's a bad design. Not about the procedures being "unintuitive". If the pilots think the corrective procedures are unintuitive they shouldn't fly any 737 since stab trim systems exist on all 737s and require the same corrective procedure in runaway stab trim.

[cmurf]

Are you a pilot? If so what are your qualifications?

Have you read the ET302 preliminary report? In particular have you read page 25, section 2 "Initial findings" last bullet which I quote:

The crew performed runaway stabilizer checklist and put the stab trim cutout switch to cutout position and confirmed that the manual trim operation was not working.

How can you read that, and say multiple times in this thread "improper procedure"? On what basis?

You have no idea how much mental discipline it's taking me, as a pilot, to refrain from ad hominem attack. Your arguments are that bad, they are that willfully contrary to the available facts.

[CorvusCrypto]

I get it. I understand everyone's frustration. In similar fashion I understand how unlikely it is a crew would have the mental capacity to deal with stick shakers, GPWS callouts, and still fix the problem and that is the tragedy here. However the report said they followed proper procedure but look at the data. 95% N1, turning auto trim on and off a few times, the last time causing the huge -2G bump. There also is not enough data to us yet to determine they did regain control of the plane before enabling electric trim again. I don't think in the case of runaway trim you are supposed to keep switching the cutoff and leave your plane above Vmo. Something doesn't add up according to the data imo.

[cmurf]

This is such a bullshit response. You don't answer any of my questions. You proceed to armchair pilot. You use terms you cannot completely understand from a big picture yet claim to come at this from a big picture perspective. That's so out of order.

Do you know a power reduction causes a nose down moment and actually makes the problem worse?

What does "turning auto trim on and off" mean? Are you referring to the you're toggle it the stab trim switches flipped between normal and cutoff? If the latter you are wrong, zero evidence that happened a few times.

There was no -2 G vertical acceleration.

What you are doing is in my view a mental disturbance. You are using terms as if you know what you're talking about. You don't. You are a bullshitter.

Please stop.

[CorvusCrypto]

Okay. Calm down for 1. Also the prelim data is there to review. The graph shows clearly there's a large plunge and there absolutely was a negative g report in the prelim showing that at the final few moments the trim settings from the FCC gave another correction. As for the cutoff, the report annotations tell you when they toggled the cutout switch. I went back and yeah actually you're right it was only once to cutoff and back to normal sorry for that mistake. However the overspeed is still supported from the data and yes the data shows vertical g forces and at the end there was a lurch of -2 Gs before total loss. It's on page 27.

As for less speed causing more nose down moment, yeah but at the same time they weren't in a descent for that portion either, nor were they nose down (this from page 26). The data shows they were oscillating though climbing slightly while they were overspeeding. In this case it could have helped to reduce the forces at play. I think it was more that they were just busy and left thrust settings where they were from takeoff.

[salawat]

Everyone hears you, most have taken your words into comsideration but I think the part you're missing is the fact that it was impossible for pilot and airline themselves to remediate problems because knowledge of the system wasn't there until it was too late, and even when information began trickling out from Boeing, it's been so slow, and so insubstantive, as to be worthless, likely because of concerns with legal exposure on Boeing's part.

The pilot's absolutely agreed to fly the plane. As far as they knew, it flew like a 737, and they knew everything they needed to know.

Boeing revealed as little as they did about MCAS to spare pilot's the "gory details" because the plane was allegedly "just another 737".

Information does not perfectly diffuse, and doesn't diffuse at all without effort. Half the outcry over this probably isn't from pilot's or aerodynamicist's at Boeing at all, but from people passionate and informed enough to get the word of the colossal fuck up out in as many ways as possible to the people who need to know it most.

I've been in these threads on Hacker News since the Lion Air incident, and held my tongue at many times. Cautioning more and more that new information will drive the development, but in all likelihood, given the facts we have access to, the problems will have occurred in X, Y, Z spots, all of which have origins within Boeing and the FAA as organizations.

The FAA delegated responsibility for vetting to Boeing. Boeing CHOSE to accept that mantle of trust, then discarded the integrity part as soon as the bottom line was threatened by a competitor.

Airlines fly planes. They don't make them. That was Boeing's job, and they cashed in on the better part of a century of goodwill, and torched the entire pile by delivering a complete failure in terms of their own responsibility to the public.

We get it. You think the pilots and airlines should shoulder the blame too. Understood. Many though, myself included, understand that the world runs on incomplete information transfer between designers and operators, and given that, an enormous responsibility is put on designers of industrial scale systems to take extra care to make sure that "unintuitive designs" are very clearly documented and made known to their operators who will have lives and property on the line.

Buying the planes from Boeing came with an implicit trust on the part of airlines that anything different to look out for would be clearly communicated. That didn't happen. They relied on Boeing doing that part. Boeing failed. The fact that armchair aeronautics engineers got to the root cause in such a short time, with so little information beyond the FDR means that it is not unreasonable for the professional engineers at Boeing whose raison d'être is to design safe planes to have caught it.

I don't think anyone here has such a severe grudge against Boeing's existence to just go after them for merely existing. Many, or at least I, am just awestruck at the magnitude of collective failure that occurred.

The data all points to them. Of everyone involved, they alone had both the means and onus to prevent what happened.

But it didn't. So here we are. Something needs to be done, we have very specific rules about how to do it, but nevertheless, something has to changed.

We owe at least that to the lost that their unwitting and tragic sacrifice shall not have been in vain.

The families that have been broken; the sons, daughters, mothers, fathers, and grandparents who will never arrive at their destination demand it. Our integrity, "Our" being those of the will, hubris, and capability to take the lives and fates of others in the embrace of our works, demands it.

Somewhere, at some point, complacency, and cultural degradation happened for whatever reason.

It must be exposed. The historical annals decorated once more in blood, that we never lose sight of the cost of any shirking of our responsibility again.

How else than this, and the penance/contrition of any directly involved, can justice truly be served?