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Comment by LeifCarrotson | Hacker News Reader

On the other hand, generalizing from two incidents to a rate isn't great statistics. The list of accidents and incidents with the previous generation [1] shows some 9 fatal problems spread over more than a decade, which is closer to a rate. But saying that the 737 Max is known to be 20 times worse when the real value might be anywhere between 2 and 200 if it had been allowed to continue flying is a little imprecise.

Put people in jail for negligence, sure. But we should be criminalizing based on that negligence and not on its results.

[1]: https://en.wikipedia.org/wiki/List_of_accidents_and_incident...

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The FAA was not just using the fact of the first crash in the risk analysis. This was the methodology they used: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgPolicy....

They would have looked at the failure rate of the AoA sensor and the failure rate of the recovery procedure and the fact that there had been one fatal crash. That gave them a reasonable estimate of the risk. Based on that analysis they should have grounded the plane, but Boeing apparently convinced them that with pilot awareness of the problem that the recovery procedure would be more effective. Unfortunately that was overly optimistic.

Indeed, here's the QRA following Lion Air Flight 610 showing projected fleet lifetime fatalities of almost 3000.

https://twitter.com/davidshepardson/status/12047953204058316...

> Unfortunately that was overly optimistic.

No, it was fraudulent. Boeing didn't make even the slightest attempt to identify all the potential failure modes, and it's still unclear if the plane is even safe to fly with MCAS disabled.

The plane cannot be certified without MCAS or some other stability augmentation. This is not unusual in itself, almost every jet aircraft has some kind of instability. The problem was that MCAS is not reliable and doesn’t fail safe. The fix they’re testing actually makes it less reliable, but when it fails it will disable itself instead of making a smoking hole in the ground.

> "generalizing from two incidents to a rate isn't great statistics."

The FAA's report, which predicted an elevated crash rate for the 737 MAX, was written in December 2018. Three months before the second crash.

Agree overall, one thing to note is that 737 Max already capitalizes on all errors corrected from 737. Max is 20 worse with all off the old system being already excluded from possibilities of malfunction (as long they are not affected by mcas or other new additions).

> Put people in jail for negligence

The higher ups new this was a tragedy waiting to happened they just hope its going to be their successors that will have to pay. Negligence is definitely too light or a term for this. This is knowingly putting people lives in jeopardy in the name of extra % in profits.

In https://news.ycombinator.com/item?id=19437938 you wrote (8 months ago):

The fault doesn't lie with the engineers who built the system...not to mention I would be very surprised if they were professionally certified.

It lies with the managers who wrote the specification that said that for business reasons the new plane must not require any additional training or type certifications, and cut costs by implementing the required systems with a non-redundant sensor.

(I agree.)

If it were just 2x worse wouldn't that still be pretty horrifying?

Let's not split the wrong hairs.

There are degrees of wrongness.

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