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Old 10-06-2014, 04:51 PM   #15 (permalink)
aerohead
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why

Quote:
Originally Posted by Frank View Post
Why? Something to do with ground effect? Isn't air moving around the wing the same regardless of orientation? (I think you're saying that a horizontal airfoil acts differently than a vertical one, is this correct?)
*Since the MC is narrow compared to its height,the convention is to streamline it using plan-view taper,which puts it in the domain of an 'uprighted,' 2-dimensional flow, symmetrical airfoil.
*The airfoil will essentially behave the same,whether horizontally as an 'elevator',or vertically as a 'rudder.'
*The part about having a full tail comes from empirical results from wind tunnel research.
*Truncated wing sections suffer enormous drag increase when their aft-bodies are truncated.
*And if they are truncated,they need to be 'closed' back their.One of the LSR motorcycles I just saw at Bonneville was tested at Darko Technologies wind tunnel,and it was found that the original open tail was a no-no as far as drag was concerned.
*Here's the mathematical relationship for wing truncation drag.You can arbitrarily 'build' some different sections in your calculator and see what the drag would be.

*And hint-hint,this year at Bonneville,a handful of LSR streamliners had finally adopted Walter Korff's full-tail boat tail,with clamshell doors over the parachute tubes,dating to Korff's 1965 Summer's Brothers' 'GOLDENROD'.of 555-mph design velocity.
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