I’ve been building wood wings for forty years. When someone came out with wood leading edges I tried it and became a believer immediately. The one thing I didn’t agree with was one size fits all. The top wing on Pitts and Eagle Bi-planes have a different air foil than the bottom wing. I also reasoned that “If Carbon Fiber is so great, why wouldn’t it be better than wood?” I had a friend hot wire a mold with his C.N.C. cutter exactly the shape of the bottom wing leading edge and the top wing leading edge; then made some Carbon Fiber leading edges using three layers of 10 oz Carbon Fiber. Then I reasoned, “ The race car people are using Carbon- Kevlar-Carbon in combination for explosion protection, why not for leading edges?” After building a few sets, I began wondering, “How do I find out which process is superior?” So my mind started mentally building a testing device. On July 13, 2014 we had a joint meeting of EAA Chapter 409 and EAA Chapter 1143. In the week preceding this meeting I gathered some scrap metal and built this device to batter three sample leading edges to destruction. Here’s a video of the results. The set up was a metal basket allowed to free fall from a 90 degree angle with weight added incrementally one pound at a time until the leading edge was destroyed. Aluminum 1st dent 1 lb 2nd Dent Each add lb Final Destruction 5 lbs Wood 1st crack 3 lbs 2nd Crack 5 lbs Final Destruction 10 lbs Carbon/Kevlar 1st crack 5 lbs 2nd Crack 8 lbs Unable to destroy @ 25 lbs
Posted on: Fri, 18 Jul 2014 04:41:42 +0000
Trending Topics
Recently Viewed Topics
© 2015