>Testing by several big trucking companies (Roger Penske's, for one) that I
>have read about over the last 10 years has indicated that the single
biggest
>source of drag for a semi-trailer is actually the hole in the air created
by
>the
>square configuration of its rear end.
I think a system of panels which could be folded against the sides and top
of the trailer before entering the loading-dock area could work here.
State laws regulating the length of the total rig could be a problem.
Circa 1972, when Corvettes Of Minnesota had one of their economy-run
rallies, one of the COM regulars showed up with a full-size van. He had a
cardboard cone (really a pyramid turned ninty degrees) taped on the front
below the windshield. I'm not sure how he decided how big to make the hole
to feed the radiator some air. On the rear, he had a huge cone of the same
design covering the entire rear of the van from top to below the bumper.
I remember that at the time I thought the thing looked very Jules Verne.
I won the outright highest mileage at one of these events with 54.054 MPG
in a stock 1968 SAAB 96 sedan with the Ford V4 and freewheel. I recall
coming over the top of a hill pacing Ray McComb in his BMW. We both shut
off our engines and coasted. By the time we were at the bottom, I was
several car-lengths ahead. Can't beat the combination of high, skinny
tires and Swedish Airplane Company aerodynamics!
Of course I got clobbered in the scoring for trophies, since they
multiplied the MPG by the number of tons the vehicle weighed (limit 2.5
tons to keep a loaded concrete truck from winning).
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