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Comment by reso | Hacker News Reader

That second 737MAX crash was full criminal negligence on the part of Boeing. The first crash was caused by bad design, the second crash was caused by Boeing’s choice to do a big PR push to prevent regulatory action and keep the planes in the air. The families should own that company by now.

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> The first crash was caused by bad design

That's underplaying it. The design was negligent, and the whole "secret" MCAS is insane.

> the second crash was caused by Boeing’s choice to do a big PR push to prevent regulatory action and keep the planes in the air

You mean the intervening time in which every single operator of the 737MAX was told to review emergency procedures? In which every platform for aviation news was focused on the behavior of MCAS and how to disable it? And in that time Ethiopian Airlines grossly failed in its duty to train its crews on MCAS specifically and upset/emergency recovery more generally, as evidenced by the accident flight. Read the NTSB and BEA add-ons to the report; I think it's clear that the crew would have been hard-pressed to recover safely from an serious event.

I really don't want to defend Boeing here, the design of MCAS was obviously grossly flawed, made significantly worse because other Boeing airframes with a similar system used multiple AoA sensors. But given that the effects of MCAS misactivation are similar to a trim runaway, which is supposed to be a memory item for 737 pilots, the inescapable takeaway is that a lot of pilots simply weren't/aren't prepared to handle rare but critical in-flight emergencies that builders and certification authorities take for granted.

> You mean the intervening time in which every single operator of the 737MAX was told to review emergency procedures? In which every platform for aviation news was focused on the behavior of MCAS and how to disable it?

Unfortunately the information wasn't enough. IIRC, Boeing didn't provide instruction for what to do if the trim wheels aren't able to be moved manually, because the aerodynamic forces are too high, and the pilots ended up turning electric trim back on, adjusted the trim, and then MCAS triggered again. Yes, there were likely steps they could have taken, such as turn electric trim back off, once the trim was adjusted, and use the trim wheels after that, maybe, but it would have been better if there was a way to disable MCAS and keep electric trim, or if MCAS had been designed and implemented with contemplation of failure in mind.

Boeing issued an unactionable memo to shift responsibility onto the operators.

73n vertical trim design and procedures are suboptimal. There should be an automation trim cutout switch to maintain powered trim control except under the most unusual circumstances/malfunctions. It's like turning off a car's brake boosters when ABS is at fault. They can't be retrimmed in full deflection nose up or down by 2 mere Schwarzenegger mortals in time to recover at either low altitude or airspeed because of surface loading.

> But given that the effects of MCAS misactivation are similar to a trim runaway, which is supposed to be a memory item for 737 pilots, the inescapable takeaway is that a lot of pilots simply weren't/aren't prepared to handle rare but critical in-flight emergencies that builders and certification authorities take for granted

Similar to runaway trim that pilots were familiar with, but from what I recall from one of the videos where a 737 pilot showed in a simulator what handling it was like and other discussion there was one crucial difference. (I may be misremembering all this though).

After the pilots handle runaway trim and have the automatic trim disabled and have manually gotten it back to what it should be, most would try re-enabling it. Most of the time when they would get runaway trim turning the system off and on would fix it.

And if that didn't fix it and you got another runaway trim, it was no worse than the previous one. You'd fix it. And if you wanted you could try turning it on again.

(From what I've seen on documentaries on other crashes, there are actually a surprising amount of aircraft systems where "reboot it and see if that works" is standard practice for in flight failures).

With a malfunctioning MCAS though there was in effect a ratchet. The down trim added by MCAS did not go away when you stopped it and manually restored normal trim. Each time you decided to try it again to see if the prior reboot had fixed it and it hadn't you got a little more down trim bias. Do that a few times and you end up with so much MCAS down trim bias that the maximum up trim you could do was not enough and you are then screwed.

The MAX needed a bold addition to the runaway trim emergency procedure along the lines of "After recovering from runaway trim, you MUST leave this system OFF".

I’m happy to see that someone else is aware of the 737’s runaway trim condition. I knew several 737 pilots who used to joke about the “wagon wheels” and considered their noisy operation an unofficial concession to monitoring.

The 737 MAX MCAS debacle is overhyped compared to the critical structural parts for the 737 NG (-600+) Ducommun fabricated by bashing and hammering fragile aircraft alloys that should've been CNC'ed. These parts contributed to numerous fuselage separations on hard landings and runway overruns, whereas in the past, aircraft bodies survived largely intact and complete. There was an long-form expose on Al Jazeera that almost no one paid any attention to. The 737 NG is a fragile POS more likely to kill you than an Airbus 32x.

> The 737 NG is a fragile POS more likely to kill you than an Airbus 32x.

TFA indicates the exact opposite.

I wouldn't want to own a company that did that. Or be forced into a relationship or moved out.

I'm not saying Boeing is a bad company. Lots of workers have put their lives into that company and believe in what they build.

I'm just saying putting ownership into the hands of possible victims seems to put more work and responsibility into their laps, not less.

I've been in abusive situations, and hearing philosophies like that worries me.

I understand it's one small part of what you said and the rest of your comment was helpful.

I think, "The families should own that company by now" is a figure of speech that means Boeing should have paid the families so much money that they no longer exist. I could be completely wrong but that's how I interpreted it.

It’s a figure of speech.

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