Date:         Tue, 30 Apr 1996 10:14:16 -0700
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         wabbott@mtest.teradyne.com (William Abbott)
Subject:      Aerodynamics...

	Vortex generators on magnetic bases... whew!!  Sounds like
fun. And strings or wool tufts to show the airflow... I think I'm
gonna have to try this at some point... on the singe cab :) (hopeless...)

	Seriously, yes, people who hack up old busses and make them
shorter for custom's are worsening their milage. Its 'fineness ratio'-
how long the bus is versus how wide/tall. Four short stories:

	Lockheed added one cockpit's worth of length to the F-80 (1 seat)
the produce the T-33 trainer (2 seats). Surprisingly, although heavier, the
T-33s were faster than F-80s, with the same engine. 

	Long ago, when the F*rd Tarus was new, a guy on the east
coast made a limo-conversion out of one. Said it went faster than
at stock Tarus, better aerodynamics.

	In the early 70s, Porsche spent a lot of DM to build beautifully
tapered long-tails for their racing cars, which rewarded the effort
by going very fast indeed. But something in the long tails' chassis would
break ('70, '71) or better team preparation carried the day ('69). The long-
tail 917 was clocked at over 240mph however- 10-15 mph faster than the
short-tails that actually won the race.

	An aerodynamicist name Kamm studied the subject and concluded that
the optimum results were often got by tappering the body as far as it
needed to go, and then just cutting it off flat. Ch*vy named the stationwagon
Vega in his honor- Kammback.

	Bill