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by gmkiv 1181 days ago
> I'm not sure if Burton was a Luddite who didn't believe in statistics or the scientific method, or if he didn't care about learning from his tests.

It's possible. It's also possible that he had a good sense of how test results are presented by program managers to Congress, and was trying to accurately convey the situation. Congress typically doesn't have time to delve into the details of the test, they get top-line results like "the Bradley did not catch fire when shot by an RPG" even though the footnotes would talk about the water in the tanks.

More generally, there is a tendency even today to make test results look good through judicious selection of test conditions. Program managers will refuse to do tests where "we already know the answer" - but only when we think the system won't work. We do plenty of tests when we have high confidence the system will work. So you get headlines like "86 of 105 hit-to-kill intercept attempts have been successful" [1], without the context that we never attempted the shots that we think we would miss, even if those scenarios are tactically important.

I'll grant that there are several motivations for testing like this, but let's not pretend that they are all purely technical.

[1] https://www.defense.gov/Portals/1/Interactive/2018/11-2019-M...

1 comments

In the case of hit-to-kill intercepts, terminal guidance was proven and reliable 30-40 years ago (at least), it is a mature capability. That is no need to test that it can hit the target per se if the rocket can precisely respond to the guidance commands.

What changed is that they later attached that terminal guidance to new high-performance rocket motors that pushed the materials science requirements to a point where it was difficult to get the rocket to respond precisely to guidance commands and the terminal guidance package itself suffered ablative damage due to extreme acceleration. As such, all of the tests for the last 20+ years have been tests to determine if the missile components materially degrade or fail in-flight, regardless of what they are aimed at. The nature of the target and test environment are almost irrelevant to this question -- hitting the target is pretty strong evidence that the materials didn't fail.