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Originally Posted by Rktman
.....[snip]..... I may just abandon my shape and use a truly elliptical planform, or give in and use a plain rectangular planform with square tip chords, which all the online calculators appear to support.
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For model rocket boost-gliders/rocket-gliders with fixed wings, AR (wing aspect ratio) can usually be chosen at values upwards of 6 to 8 depending on the strength of the wing materials. AR values of 10 or 12 or higher begin to push the bounds of where aerodynamic flutter will damage the wings.
The value of AR is found through dividing the square of span by total wing planform area:
AR = (b2) / S
Model rocket boost-glide or rocket-glide designs with pivoting wings, folding wings, etc., are a whole different animal.
Taper ratio for subsonic wings (usually represented by the Greek letter lambda, but go ahead and use TR) can range across a variety of values and still get you a wing design that is 95+ percent of the efficiency of a true elliptical spanwise lift distribution, without all that PITA goofy calculation for a complex shape like an elliptical wing planform. TR values of .20 to .30 get your wing efficiency into the 99 percent neighborhood.
The value of TR is found by dividing the wingtip chord by the wing root (projected to centerline) chord:
TR = cT / cR
Using a trapezoidal wing planform (tapered or constant-chord, your choice) also has the huge advantage of making it much much easier to sand a consistent leading edge shape, trailing edge thickness taper, and even the spanwise wing thickness taper.
If you are lazy like me, you will go straight to a trap-wing design.
BTW, I do indeed admire the lines of the Spit, but like I said before, that is a clumsy way to seek to achieve high values of wing efficiency.