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Old 10-19-2012, 11:08 PM   #210 (permalink)
Sven7
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Quote:
Originally Posted by freebeard View Post
Another good example. Am I correct in thinking the fins being canted inward towards the rear is to reduce yawing in crosswinds?
I'm guessing if you tufted the car the fins would be parallel to the airflow coming off the rear window.

Quote:
Originally Posted by christofoo View Post
I was thinking a single vertical stabilizer in the center just to enhance the airplane look. You could even go all the way and add some little stubby horizontal stabilizers and arrange an extra-large third taillight to look like a jet nozzle.

A vertical stabilizer might help keep Cd from increasing at high yaw angles. It also may slightly increase Cd at low yaw angles. I doubt it matters much in either case.

I wouldn't expect side-winds to affect the car much from a handling standpoint either. Look at the side cross-sectional area of an SUV, does you expect it to be unsafe in side-winds? (Sure it's going to sway more than a sedan.) Side-winds do make fabrication and attachment of the stabilizer a little more challenging, but no more so than on a real airplane.

To me its just a question of aesthetics. Is it, in fact, more fun to make a teardrop car look more like an airplane?
Maybe the physics guys can weigh in with jargon, but when you have a fin out back on a boat tail it effectively creates a lever with which to move your car around more easily (the rear tires are the fulcrum). Most of an SUV's aero cross section is between its axles, not behind the rear bumper, so wind has little mechanical advantage.

I've noticed the Probe is more susceptible to side winds now- a big fin on the back would be downright scary sometimes.
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