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Comment by jonplackett | Hacker News Reader

Since the main battle to getting this plane flying again is going to be public trust, I think they’re going about this all wrong.

First admit full responsibility. Then at least you have a shot at people trusting you to fix it.

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At this point the planes either need to be retrofitted with their original engines or scrapped. They will remain flying deathtraps no matter how much software is piled on to patch the issue.

Why? What I've heard is that if the pilots know how to disable the pitch correction, the plane won't fight them in the event of a sensor failure and they can land safely.

From what I've heard, trimming a large jet engine plane by hand is physically difficult, even if you manage to disable the MCAS system. Additionally, I believe the core issue is that pilots were meant to fly these plans without additional retraining, which is why MCAS was added in the first place.

Isn't that exactly what happened with Ethiopian Airlines? The pilots knew about the MCAS, knew what was happening, disabled the system, but were unable to physically adjust the trim to prevent the crash?

I’ve not read anything that suggested they knew about MCAS. They knew about automatic stabiliser trim, which is a different system also present on the older 737 NG. The way MCAS monitors angle of attack, and the way it is temporarily disabled by pilot trim inputs was not known to them.

They followed the recovery checklist. Step 1: Use the trim cut-out switches to stop MCAS. After the first crash, any MAX pilot would have to be a moron to not be informed about the issue and Boeing's (useless) guidance to resolve it.

Yes I agree, they knew about the possibility of runaway stabiliser and they were not morons. Boeing’s guidance was useless to them because it left out a description of how MCAS operates, and I’m not sure it even mentioned it by name but I may be wrong on that.

If they had known that MCAS is disabled for 15 seconds by pilot trim inputs, they could have saved the plane. Toward the end of the flight they went off-book and re-enabled auto trim, blipped the trim a few times and 15 seconds later MCAS jumps on and dives them into the ground. All they needed to do was keep making small trims.

> If they had known that MCAS is disabled for 15 seconds by pilot trim inputs, they could have saved the plane.

I understand it as "if they were able to consistently, all the time, until they land, fight the plane which was trying to kill them every 15 seconds turning the nose to the ground, resulting all the time in even harder position (due to the forces involved) they would..."

Flying death trap indeed.

Perhaps, but it's understandable why Boeing is parsing their words carefully here. For some critics full responsibility would mean nothing short of Boeing admitting the 737 design had reached end of life and they should have never tried to shoehorn larger engines onto the 737 airframe. That would mean ceding the trillion dollar narrowbody market to Airbus for the foreseeable future.

I just think they need to accept responsibility for all those dead people.

Personally I don't see anything wrong with the idea of the redesign. It's the execution that was the problem.

If he came out and said, look we screwed up. There should have been a backup sensor/proper training/proper manuals/software that took a bloody hint and maybe there should be more gov oversight in general because this kind of cock up should not be possible. At least then you'd believe they're actually tackling the problem.

Reading all that back, it is actually quite a lot to ask for isn't it.

> Personally I don't see anything wrong with the idea of the redesign.

You don't think that there's anything fundamentally wrong with designing an aerodynamically unstable airframe, that needs software overrides to keep the plane flying?

A 737 shouldn't fly like a fighter jet.

It’s not like the plane was uncontrollable without MCAS, it’s more that it did not fly like a 737-NG, and so would have required extra pilot training to compensate, which would have made the plane less attractive to airlines.

Probably should have said _a_ redesign rather than _the_ redesign. But even so, if they’d been up front about what they were doing and why and put proper safety systems in place I don’t think it’s that different to other planes is it? They just did it badly and secretly.

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