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Old 03-22-2011, 08:06 AM   #7 (permalink)
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Svietlana II - '13 Peugeot 308SW e-HDI 6sp
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Originally Posted by johnlvs2run View Post
Wouldn't that just slow you down more?

I think a truck doesn't pull the wind forward, it just provides a barrier and lessens the force of the wind.

So having sails would counter the effect of the truck, would catch more of the wind and slow down your car.
The air in the wake of a truck is moving forward relative to the ground, but some of it may be moving forward relative to the truck, i.e. it is moving faster than the truck (relative to the ground). Relative to the truck, a drafting car is not moving, so that small portion of air is moving forward from the car's POV. Of course, this is all happening inside the wake (and/or close to its outer edges), so you have to be very close to catch it. Maybe a small, vertical piece of plexi at the front of the car's hood could barely catch the draft, but any variation in distance from the truck, or a gust of cross wind, could suddenly have that plexi pushing instead of pulling you.

In theory you might see a small gain, but in practice not enough to sacrifice safety. At that distance a tow bar would be much better.
e·co·mod·ding: the art of turning vehicles into what they should be

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