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View Full Version : Solid leading edge wrap? Benefits?



danawalker2@gmail.com
12-19-2011, 06:40 PM
I am looking for information anyone has to the benefit of a solid leading edge or wrap for poly fiber cloth covered Challenger II wings. How wide, where to set it in regaurd to the front wing spar tube, what thickness of sheeting?
Is it worth the effort and weight difference? Does it tend to buckle or ripple in temp changes?
Where is the best place to buy the sheeting?
I would greatly appreciate any assistance. I am converting sailcloth wings to poly fiber and installing fiberglass wing tips. If there is a benefit to adding leading edge wrap I want to do it now but I want to only do it once and do it right.

Eric Witherspoon
12-20-2011, 01:16 PM
First off, I don't have a lot of experience with fabric. Took the Sportair class, and that's about it. However, I am building a tube-and-fabric design which may have some commonalities with what you are describing.

The one I'm building uses a tube spar with wood ribs. The plans do show a thin sheet over the forward portion of the ribs. How this is implemented is by bonding spanwise support members across the ribs at the aft-most point where the leading edge sheet terminates.

That way, when the sheet is bonded on, there is some support to keep it from bowing in or out along the trailing edge of the sheet.
I don't have the plans in front of me, but I can check what dimensions they call for the spanwise support as well as the sheet.

I would think the advantages would be:
1. Greater torsional stability to the entire assembly. May not be important in your case, because rigid structure was not needed before.
2. Better aerodynamic shape - no change in the airfoil section between the ribs. Again, may or may not be all that big of a difference, but the wing should be somewhat more efficient.

danawalker2@gmail.com
12-21-2011, 04:25 PM
Here is an idea I want to get other's input to. Would a strip of medium poly fiber 12"-18" wide going from the inboard to outboard boxes and covering the curve of the wing rise and heat shrunk before installing the wing covering, possibly keep the covering fabric from sinking between the ribs? Would the shrinking of the strip going only end to end be enough to keep the covering fabric from pulling front to rear giving the dipped look? It would be less weight then metal.