Also consider: a 3 foot (1/8 scale) airplane facing into a 20 mph (29 ft per sec) wind is experiencing a scale headwind of what a full sized airplane would with a 160 mph wind (232 ft per sec).

I know this doesn't work because most models are flying at far-greater-than-scale speeds and, as Montague pointed out, the relative air is denser for the model. A full sized plane also weighs considerably more than 8x the weight of a 1/8 scale model. Like pounds to the nth power instead of pounds times n scale ratio. Just another fly in the ointment of model aerodynamics.

Remember, as Mark Twain stated, there's three kinds of lies: Lies, Damn Lies, and Statistics.