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Max Sluiter
 
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Join Date: Mar 2006
Location: So Cal
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Quote:
Originally Posted by gsmith660 View Post
From schoolphysics.co.uk first website I went to pertaining to infrared radiation:

Black surfaces are the best emitters of heat radiation.
Black surfaces are the best absorbers of heat radiation.
Shiny surfaces are the best reflectors of heat radiation.
Shiny surfaces are poor absorbers of heat radiation.
Glass will not transmit heat radiation.

That would suggest a black reflector would in fact move the heat closer to the motor just sayin.
That makes sense then. The Habu was getting really freakin' hot because it was going so fast (atmospheric friction). There was hardly any air up there to get convective cooling so they wanted to maximize the radiative cooling.

So, since the heat was not being radiated onto the Blackbird, but rather being created in it by the atmospheric friction, they painted it black to emit the infra-red radiation.

Yes, it made it visible to IR detectors but they had electronic countermeasures and not much could touch them at Mach 3.2 and 85,000 feet or more in altitude.

(I've been reading a great book on the whole A-12->SR-71 program by Crickmore).
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1971 chassis, 2.7RS spec MFI engine, suspension mods, lightened

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Old 01-02-2012, 02:21 PM
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