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Old Sep 15, 2002, 04:15 PM
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Scott Black, Montreal
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montreal quebec Canada
Joined Sep 1999
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You haven't mentioned the most critical aspect of the 2 airplanes - the weight. My first impression is that this is a huge airplane for 8 cells. If your weight is around 3 lbs, you have something like 15 oz wing loading. To have decent aerobatic performance, and I don't mean being able to hover and flit about like a 3D airplane, but good sport aerobatics, you want to be up around 18-20 oz wing loading i.e. a smaller airplane which amounts to less weight and drag. My 10 cell (2400s) pattern ship has 350 sq in and uses a 10% section.

A huge airplane, with an 18% wing section, is not going to have good endurance at high speed. Make it smaller and lighter, or else put more cells in, then use a 10% thick wing, symmetrical or slightly cambered doesn't make a whole lot of difference.

The most fundemental parameter in airplane design, the one that has the biggest impact on how the airplane flies, is the sizing vs the power system and weight. The choice of wing section is not nearly so important.

Now I want to be clear here - there are lots of funfly type 3D airplanes with 12 - 15 oz/sq ft wing loading, and if that is what you want they fly great. But if you want to do large, smooth, scale type pattern or IMAAC style flying you need something with some power that can fly fast. You need 18-20 oz wing loading and 75 watts/lb+.

The wing loading will determine the speed at which the airplane flies and hence its flying "style".

An 18% thick wing is appropriate for a 3D airplane, but almost 100% too thick for a fast, smooth, pattern-type airplane.

So I don't think your decision is as difficult as you think. Chose the type of airplane you want, then go for the wing thickness that the chosen type requires. Whether it is symmetric or just mildly cambered doesn't matter all that much.
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