Quote:
Originally Posted by mwilliamshs
...where should I expect to find the point of maximum drag reduction per length?...
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Looks like max benefit per length is at the point of the blue arrow which appears to be exactly .25 (x axis). Of course that length on that diagram isn't universal for all others but it's what I'm hoping to find
My h = 85", so d = 170", 1.78d = 302.6"...how do I find L? Is it 1.78d + body - 10%? That's 302.6" + 225" = 527.6" - 30.26" = 497.33" (~ 41' 5"!)
So IF (bigun) I'm interpreting all of that right, .25 of 1.78d is the tip of the blue arrow and IF that's accurate to the van I need a kammback of 302.6/4 = 75.65" to reach that .25 arrow.
BUT...
That diagram actually shows L as tail length and D as height, so L/D = .25 is the same as 4L = 1D. My height(D) is 85" so .25D = just 21.205" for that blue arrow. I like Mair!!
BUT...
Scratch that. Reread it. D = 2h still. 170/4 = 42.5" tail length for .25 l/d. Still not unimaginable.
At that length, a tail with 4 straight sides and a top taper of 15°, side tapers of 15°, and a bottom taper of 2.5°, would have back-edge dimensions of 57.25" wide and 71.83" tall, call it 5' x 6'.