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Comment by onli | Hacker News Reader

> You would actually have to try really hard to fuck this up.

Murdering 350 civilians with lies and negligence for profit and "shareholder value" just might suffice.

They put a plane into the air that flies itself automatically into the ground after all, with no opportunity for the pilots to save the plane. You can't fuck up more.

> It would be amusing if the US government gives them money though.

The US is already giving them money, indirectly. The EU is just also giving Airbus money. That's the core of the issue of Trumps position and why the conflict can't be easily solved.

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> They put a plane into the air that flies itself automatically into the ground after all, with no opportunity for the pilots to save the plane. You can't fuck up more.

Though Boeing has significant contribution, if you read the report on the Ethiopian Air 737-Max crash, I think it's easy to see several places where there was ample opportunity for the pilots to save the plane, particularly in light of the LionAir crash. Even in the LionAir case, a prior LionAir crew did save the airplane on an earlier flight by following the manufacturer provided checklist.

Boeing made a serious design error here. However, it's not nearly as serious as the quoted sentence, IMO.

I was honestly under the impression that the provided checklist did not work, as it included elements that did not work in the 737-MAX as expected when coming from earlier models. Plus the fact that the forces were to strong, the pilot could not manually correct the course.

Besides, did the pilots have opportunity to read and implement the new checklist?

There was no new checklist. (Arguably, this may be a problem.)

The existing checklist was unchanged from other 737s and the required actions were all "memory items" (items which must be recalled and implemented by the crew from memory, prior to referencing and completing the written checklist in the QRH). Any 737 crewmember would have had to have demonstrated those checklist items, from memory, prior to receiving their type-rating to fly the jet. Runaway trim is a "no joke" event in nearly any type and is a memory item in any type I'm familiar with.

The Ethiopian Air crew seemed to correctly diagnose the issue, got the aircraft somewhat under control and then, in an attempt to fix the trim issue, undid the corrective checklist item, ran the trim aircraft-nose-up using the thumb switch (so far, excellent!!) and then, inexplicably, left the stab trim power enabled without commanding further aircraft-nose-up. So, they diagnosed the issue, initially did all the right things, then undid them [with good reason], then failed to re-do them.

(I agree that Boeing still wears a lot of blame here. It's just not the case that the crews were helpless and unaware passengers.)

Well, okay. https://www.theverge.com/2019/5/2/18518176/boeing-737-max-cr... agrees (though I vehemently disagree with its title when interpreting it as referring to pilot errors! But that might be the point). Problem seems to be that it was basically impossible to realize which checklist to follow and to identify the problem. I think my sentence when interpreted with that in mind still works (and you are still right as well): Pilots had no opportunity (several reasons, like not being informed about system changes) to save the plane, but not it was 100% impossible during the whole incident to save the plane (it was probably impossible after they deactivated the electric trim system).

It's not just the checklist: the experience of MCAS-induced trim runaway is significantly different from that which NG pilots are trained for, to the point where additional training seems necessary. Boeing set up the conditions for an accident by first hiding, and then downplaying, those differences, apparently to avoid additional training being required.

I have seen some suggestions that this was also the reason for not having MCAS compare the two AofA sources to detect a fault, as the fault would have to be reported, and the documentation of that indicator would reveal the existence of MCAS.

I agree with you, hence the "arguably, this may be a problem" parenthetical.

Nevertheless, the provided checklist did work as evidenced by Lion Air 043.

So the checklist worked sometimes, but the question is, could it have been improved if we put aside the issue of whether doing so would make a case for additional training?

It is quite possible that it would have been an adequate checklist when backed up with sufficient training that emphasized the differences between MCAS-induced trim runaway and that which might have been experienced in other variants. Simulator practice of manually trimming might help as well, though there is some doubt whether current simulators can adequately model the difficulties that may be experienced.

https://www.youtube.com/watch?v=n4qDLR4s45U&t=296s

Note: the penultimate flight had the luxury of a third pilot in the cockpit with nothing else to do than to pay attention to anything the other two pilots couldn't.

Also, that "checklist", and he existence of MCAS, was not even commonly known until after Lion Air went down.

The secrecy behind this is largely attributed to Boeing trying to keep MCAS from intense scrutiny by the FAA, based on whistleblower testimony reported in the 60 Minutes Expose.

https://m.youtube.com/watch%3Fv%3DaO7_indbfME&ved=2ahUKEwiPp...

Human error by flawed UX is still a design issue.

Didn't the crew save the airplane because there was a third person there to help manually trim as the force required was too much for two people alone, whilst also having to pull back on the yoke with massive force?

That means it was dumb luck (a third person being there) and not due to following procedures if those procedures are nearly impossible to follow, or require superhuman strength.

No; the third crew member on prior Lion Air flight (043) is the one who diagnosed the issue as runaway trim and cued the flight crew to execute that checklist. I've read nothing to suggest that they participated physically in the response (despite having read quite a bit on the topic).

The excessive force on the trim required in the Ethiopian Air case was a consequence of the crew leaving the engines at high power, the trim having run farther nose down, and the elevator being held nose up, resulting in loading the horizontal stabilizer thus making the trim difficult to move. (Though I'm critical of their decision to restore and leave power to the trim system without commanding aircraft-nose-up after correctly diagnosing runaway trim, I don't really fault them for leaving excessive power in. That's a reasonable response to the initial indications and by the later time they realized it was a trim issue, they were pretty well loaded up struggling with the airplane that was well out of trim, so undoing their thrust command [which would typically result in a descent that they didn't want/couldn't afford] probably isn't reasonable to expect.)

One should however mention that the failing sensor gave an "unreliable airspeed" warning. The checklist for that requires a designated power setting as well as a designated pitch for which the airspeed is known for the altitude. Afaik the pilots executed that checklist at least for the power setting part before moving to the stab trim runaway memory item. The failing AoA sensor triggered several checklists to work on.

From an armchair perspective a checklist for AoA sensor failure would have been required for the flight to end safely (maybe with "cutoff stab trim" on the list).

This would have been complicating in Boeing's attempt to get the plane certified without simulator training, as it would have raised inconvenient questions as to why a previously non-safety-critical sensor suddenly needed a checklist, which would have kicked off a chain of very difficult and expensive to remediate questions upon a more in-depth, impartial design review.

You _have_ to be kidding me. The air plane, as proven by two crashes that killed every occupant in the plane, was fatally flawed. Boeing is negligent and the executives who ARE ultimately accountable should pay the cost.

He did not claim otherwise. He just corrected a statement of mine which could be interpreted in a way to be factual incorrect.

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