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Old 10-12-2015, 05:39 PM   #45 (permalink)
aerohead
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untenable

Quote:
Originally Posted by freebeard View Post
With my brass caliper and the screen (reduced to Normal from an eyeball friendly size) the Kamm K-car is 123% the length of the Beetle (I love that choice for baseline). Assume a 12ft length for your typical bumperless Beetle body and that makes the K-car 14.76ft. That's close to my own estimation of 3 additional feet (i.e., 15ft) to boat tail the body.

The full boat tailed body is untenable. Suppose for a moment that the K-car body has a Magic Butt Trumpet. Rather than a taper to a straight line, the trailing edge is a half-circular arc and the underside is half an exponential horn. It could even transition between square 'twixt the rear wheels and circular at the tail.
yes,there's been a complete consensus over time that the full length is a non-starter.Jaray wouldn't even do it,and he developed the 'combination' form as a compromise,joining a vertical airfoil section to a horizontal one.
Unless the tail was 'active,' it would be completely impractical.
As to the 'butt trumpet,' we ought to have a sketch so everyone's on the same page.Like Bucky Fuller,I'm reluctant to approach discussing a concept,unless I've got a model or drawings to help others visualize it.
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