Boeing Built Deadly Assumptions into 737 Max, Blind to a Late Design Change

Re:Boeing Built Deadly Assumptions into 737 Max, Blind to a ... by CydeWeys on Saturday June 01, 2019 @07:12PM (#20072358)

ABS isn't the best example because it does prevent lots of accidents in its own right, including a >50% prevention rate of some types of accidents in rainy, snowy, or icy weather. The overall fatal accident reduction is 15% for cars and 27% for trucks and light trucks. Source: https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/...

And, anecdotally, I've had ABS kick in in some occurrences for which I was very thankful.

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Re:Boeing Built Deadly Assumptions into 737 Max, Blind to a ... by cameldrv on Monday June 03, 2019 @12:27AM (#20080412)

Having a safety system that rarely fails to prevent an accident is much different statistically than a safety system that rarely causes an accident.

Suppose the crash probability on a normal flight is 1/1E7, but without MCAS it's 100x more dangerous, or 1/1E5. Suppose MCAS failure probability is 1/1E6, the probability of an additional crash due to the failure of MCAS is 1/1E11, which is acceptable.

The problem is that in practice, the crash probability if MCAS fails is empirically 2/3 instead of 1/1E5, because MCAS actually causes the crash rather than merely failing to prevent a crash.

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Re:Boeing Built Deadly Assumptions into 737 Max, Blind to a ... by perl4ever on Sunday June 02, 2019 @11:26AM (#20076037)

The first thing I read in your link seems to be the opposite of what you wrote:

"ABS has close to a zero net effect on fatal crash involvements."

Further down, there is a chart which seems to show that ABS is associated with a huge increase in fatal accidents in inclement weather, and a large increase in side impact accidents, both fatal and non-fatal.

Maybe there's something obvious I'm missing?

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