History, Politics And Current Affairs

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PostPosted: Sat Dec 03, 2016 2:47 pm 
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So the PM has said previously that he does not wish to rate never-flown aircraft on the basis that their actual performance cannot be evaluated and the manufacturer's estimates tend to be unreliable at best.

But I got to thinking (always a dangerous business) if one can analyze the estimates themselves; since we must be able to compare manufacturer's estimates to actual flying performance to know that the estimates are wrong, I found myself wondering if there might be a consistent relationship between overblown claims and real figures. That is, if you put in overhyped estimates for a series of birds (perhaps by country, since it's been noted that the Germans have been a key culprit here) and compare them to the actual ratings, does a Coefficient of Estimates emerge? Say if German fighters would consistently rate as 20% better if rated by their paper statistics; then we would have a tool to deflate estimates to an "expected" figure, and perhaps be able to rate paper aircraft.

The null hypothesis would be that estimates vary essentially randomly; I would expect to still derive an average coefficient > 1 (as I don't expect paper estimates to often understate the performance of an aircraft), but its predictive power in that case would effectively be nil.

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PostPosted: Sat Dec 03, 2016 3:27 pm 
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Well the thing is I'd expect them not just to vary by country, but also by time: a German proposal in 1939 would probably be "off" by a different proportion than a 1944 Napkinwaffe.

(And of course it might also vary by company, from "we've crunched all the numbers" to "we're here, give us the contract" like Grumman did to lose the S-3 to Lockheed...)

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