737 problem explained

Cite? Lockheed is not part of Boeing.

Dan

Do we know that it was the marketing department that drove the original design decision? Or was it marketing that overruled the few engineers who complained? They may have been overruled by other engineers but there is simply no record other than what marketing said.

The left always says the market exists for shareholder earnings, and the right says it exists so producers can make what people want. It exists for the same reason democracy exists, so that people can decide what they want. We don't have democracy because people make the right decisions, but because freedom is more important than making the right decisions.

If the purpose is to "change the handling characteristics" then you should be able to override it using only the yoke.

Then you would have 2 sensor failures, attitude and rate of climb.

and it might have been if they had set some reasonable limits on how much trim MCAS could do

I can assure you that marketing does not have absolute power to force bad d ecisions on engineering. In companies like this requirements definition is a group effort of all departments. Engineering must have thought they cou ld include the MCAS in a safe manner or it would have never been approved t o go forward.

Every bit of that sounds like nonsense. Besides, there is no such thing as the "right" decision in many situations. There are trade-offs and which i s preferable is often a matter of opinion even after the fact.

Agree with the part about what happened. But I see a simpler solution and again it's a Boeing FAILURE. After the first crash, Boeing put out an emergency directive to the airlines on MCAS and how to deal with it. The procedure was to treat it as runaway trim, which is what you outlined above. And the problem with that is that, like you say, it can be impossible to turn the trim wheels by hand. Boeing either knew that or should have known it, with all their history of 737 and other planes. What would have worked? The procedure should have been:

2 - Use the trim buttons to move the trim back to a near neutral position, if possible. Then immediately hit the electric trim cutoff switches. (And that would have worked if it was an MCAS AOA failure.)

They did describe how MCAS is disabled with flaps applied. But the Ethiopian pilots didn't try that. It's also remarkable to me that in both crashes, the big trouble started just as soon as they retracted the flaps. IDK about you, but when something goes awry with anything I'm involved with right after a change of some kind, on my list of what to try first is to undo what had just changed. But none of the pilots on any of the flights thought of that. One factor is that when you're in crisis, I'm sure it can be real hard to think about what to do.

And oddly, so far, we've heard nothing about what was wrong with the one that was replaced on a new plane? What was wrong with the replacement? I heard earlier on that they thought the Ehtiopian sensor could have been hit by a bird, but nothing since.

Another big failure was that there was no check in the MCAS software as to whether the AOA were in a normal position while on the ground. One of the crashes at least, it was showing like 35 deg while sitting on the ground. Also, the mechanics replaced a bad one, right? It's just a swinging vane, you would think once replaced, they would verify that it's reading normally.

Are you sure that's correct? First time I've heard that. Many pilots have ratings for various aircraft and I thought they were just cumulative.

but when there would be 737.ng and 737.max typeratings

NEver heard that was the problem. Only that it would require more training to get a type rating for a new plane and that then pilots could be moving between two different planes when going from one

Not so sure about that either. I read an MIT aero engineer saying that without it, the plane behaves in a way that is undesirable in commercial aircraft.

and if it still was added the pilots would have

I don't think there is any issue of a redundant system not being allowed. It's that Boeing wasn't going to make it redundant because among other things, it would have cost a lot more. They even charged extra for an AOA indicator and for an AOA disagree light, something like $10K. And then it turned out the disagree light in planes they sold was not actually working and Boeing put fixing that on the back burner, part of a future software update that never happened and didn't tell the airlines.

All I know is I went from preferring to fly on a Boeing plane to now preferring an Airbus if it's been made in the last five years or so. And that CEO should have been fired a long time ago.

Overruled what exactly? Marketing came to a very reasonable conclusion, that they should build a new, more efficient 737 that flew like previous 737s, that didn't need a new type rating, that would save it's customers money in training, that would allow pilots for carriers to fly 737s that all behaved similarly? That's what they would have had to overrule.

As I understand it, it was only much later, possibly after the first test flights, that they realized MCAS was needed to make it fly the same.

I corrected that in another post, I meant McDonnell Douglas.

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That's certainly true, but it's different than there being an actual prohibition of some kind that bars multiple type ratings.

Of course it does to someone who disagrees with the philosophy of the founders and thinks he knows how to design a government and a system of elections better than they did. If you were there 200 years ago we would have had a gulag.

No, it's just you making up nonsense.

Classic loose thinking.

We don't live in a democracy. We live in a representative democracy.

Living in a democracy leads to destructive idiocies like brexit.

:)

Loose because I think we have a direct democracy? I don't.

In the US we live in a representative republic. Many think it should be a democracy instead.

The fact that it's not direct doesn't impact what I said about people making bad decisions, and letting them decide anyway.

I was just reading a little small town paper and remembered this. It seems that small town papers are never paywalled. Nobody is funding them from the shadows.

Thanks.

For the most part your distinction between the two have nothing to do with your last part about making bad decisions. The representative republic doe s nothing to prevent bad decisions unless they have to do with individual r ights as protected by a constitution.

Are you suggesting these "bad decisions" you refer to are about individual rights that are protected by our Constitution?