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Old 01-27-2020, 11:51 AM   #8 (permalink)
freebeard
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Paraphrasing aerohead here: Reynolds number determines the low speed end of aerodynamic drag, depending on barometric pressure and temperature, at ~25mph for vehicle sized objects. Scale models need to be in water instead of air to compensate for scale.

At the high end, transonic shockwaves cap the range of speeds when the formulae apply.
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