difference in wing shapes
#1
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I've got 3 ... well ... 2 gliders and a "wannabe", and all 3 have different airfoils. The wannabe ... a Gull 1900 has a regular but steep dihedral wing, and requires quite a bit of speed to keep it afloat. My Spirit and Riser both have a polyhedral wing, but the outer wing section on the riser is bigger than the Spirit. It's been kinda breezy the past few days, so I haven't been able to fly the riser to see if it flies any different than the Spirit. As far as weight goes, the airframe on the Riser is about 8 ounces lighter than theSpirit with the same radio and servos in each. Does the difference in the shape of the wing have anything to do with weight distribution, or is one meant to turn better ...? Or is there really no difference other than outward appearance?
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Wing area distribution (shape) and dihedral on rudder/elevator sailplanes does have various effects on maneuverability. Too much polyhedral can make the sailplane too stable. Not enough and you can't turn it with the rudder.
Weight and airfoil will affect performance. A thick airfoil on a light plane will make it slow. A thin airfoil on a heavy sailplane will hurt the distance to altitude ratio. All factors need to be considered when designing a polyhedral rudder and elevator RC sailplane.
Weight and airfoil will affect performance. A thick airfoil on a light plane will make it slow. A thin airfoil on a heavy sailplane will hurt the distance to altitude ratio. All factors need to be considered when designing a polyhedral rudder and elevator RC sailplane.