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Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

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Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#11
post #10

Half of pilots are going to be below average - why not test against their ability?

You’re thinking of median, not average, but your question stands.

The arithmetic mean (I.e. the average) is the 50th-percentile (I.e. the median) in a normal distribution. The question absolutely stands - unless pilot ability is not a normal-distribution.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#13
post #10

Half of pilots are going to be below average - why not test against their ability?

You’re thinking of median, not average, but your question stands.

Median and mean are both averages, and there are other types of averages. Average by itself doesn’t imply mean. And of course it’s median - how can you have a mean of something discrete like group of people?

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#15
post #7

I wonder if a bigger factor would be the test pilots knowing in advance what the test was. Eg. being told, "next we are testing what happens when MACS fails", whereas in a real life situation the pilot has to diagnose what has happened, recall the correct remedial action, then act on it.

Also this test pilots may know the inner working of the plane where the real pilots were not told that MCAS was added behind their backs and some buttons/switches changed behavior.

Also were this test pilots had accessed to extra diagnose data where regular pilots were not provided even with a sensor disagree message

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#16
post #10

Half of pilots are going to be below average - why not test against their ability?

You’re thinking of median, not average, but your question stands.

"Average" is a blanket term which includes median: https://en.wikipedia.org/wiki/Average

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#17
The primary design objective of the 737 max was to avoid pilot retraining. Until that stops being a major economic driver in aviation no problem was solved here.

Changing MCAS another dozen times and updating the manuals does nothing to prevent this from happening in new future system design.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#18

If you test for average pilots, then you've still got approx 50% of pilots who aren't capable. Whatever happened to testing for the lowest common denominator - especially in life and death situations?

Good idea - any shit pilots want to volunteer? ;)

I don't think it'd be any kind of a challenge to find shitty volunteer pilots, you just restrict your search to PPLs.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#20
post #10

Earlier quoted context omitted.

You’re thinking of median, not average, but your question stands.

The arithmetic mean (I.e. the average) is the 50th-percentile (I.e. the median) in a normal distribution. The question absolutely stands - unless pilot ability is not a normal-distribution.

Since there is a long training/weeding-out process I would expect the distribution would be truncated normal, with some cutoff to graduate plane school. If this bar is low then the distribution will still be roughly normal, but if it's near or about the mean (does anyone have the fail rates?) then the distribution can look a lot different, e.g. one-sided normal, or power-law.
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