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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

#31
I have 15 hours in a Cessna 172, I’d be happy to give it a go!

But in all seriousness, in no way shape or form should the testing be informed by the skill assessment of the test operator.

The analysis should be looking at the tasks that had to be performed during the test, whether they were properly identified by easily selected checklists, and quantitative measurements of the complexity and physical difficulty of the tasks.

If it comes anywhere close to a question of the skill or strength of the specific test-taker then something has gone terribly horribly wrong.

In old school UI testing you would do GOMS analysis which allowed calculating the difficulty of specific tasks based on the actual manipulations required to perform them. The skill of the particular operator is not generally a factor in these types of analysis.

The subtitle of TFA states;

> Safety board says FAA should embrace data-driven approach to assumptions about pilot responses

This is a much more reasonable statement. For instance, the maximum physical force required to perform the task must be an industry standard that pilots are all certified to be able to perform.

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

#33

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.

There’s a tension between progress (some of which offers fuel [and ecological] savings) and cost.

If you can make a plane that saves an airline $1MM/year/copy but costs them $4MM extra and $500K/yr in training costs, you won’t sell as many as if it costs them $3MM extra and requires no retraining (or even $5MM/$0). Sometimes that difference is enough to make the project not viable economically.

Certification is incredibly expensive. The airplane I fly the most was built in 1997 on a type certificate (the basis of certification) originally approved in 1958. That’s incredibly common.

Passengers complain about terrible seats, terrible service, jam packed flights and then search for tickets on price as the overwhelming factor. It’s little surprise that airlines are competing mostly on price.

I’m not sure what you’re suggesting here as the solution to make it [pilot re-training?] “not a major economic driver”. It could be “reduce training costs for everyone” or “increase training costs for everyone” or something else.

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

#35

I'm not sure the criteria for determining an 'average' pilot but if becoming a test pilot is a big incentive for trying to be the best you can wouldn't this drag the average pilot quality down?

There's a role for test pilots in aircraft development, and certification pilots, used in rating an aircraft for commercial use.

You'll want the good ones for that first task.

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

#36
Of course it should be. But the precedent was set in the early days of aviation when test pilots were flying experimental aircraft from alpha to v1. You don't want to kill rookies who freak out in a flat spin, so you put your coldest mfer in the seat.

And then they do barrel rolls during the first public flight of your 707.

But now that we've got such accurate virtual cockpits, we don't have to worry about killing pilots as much.

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

#37

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.

There's a lot of safety value in not having to be retrained, too.

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

#38
post #23

Wouldn't you need the worse pilot you can get? Average doesn't account for the fact that 50% of the sample are WORSE.

But that's median not average...

Given set: 1 2 2 2 2 2 4 10

What's the average? 3.125

What's the median? 2

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

#39
post #31

I have 15 hours in a Cessna 172, I’d be happy to give it a go! But in all seriousness, in no way shape or form should the testing be informed by the skill assessment of the test operator. The analysis should be looking at the tasks that had to be performed during the test, whether they were properly identified by easily selected checklists, and quantitative measurements of the complexity and physical difficulty of th…

It would be interesting if all of the airlines' own recurrent simulator sessions (every 6 months, IIRC) resulted in data being fed back to the FAA. You've got a huge sample size right there, and they try out all of these unexpected scenarios.

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

#40
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.

Why would a competitive, high skilled role with aggressive disqualification requirements be anywhere close to a normal-distribution?
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