Originally Posted by The Don
The trailing edges are just one part of it. The key is total model drag reduction. Any drag reduction will gain you more speed. Simply sanding the trailing edge thinner may or may not work depending how it is done because you are altering the airfoil by sanding it. You can reduce trailing edge drag but then gain profile drag from the modified airfoil section if the sanding is too abrupt. Thin airfoils have less drag, smooth surfaces have less drag. The ducting, control rods in the airstream, it all adds up. The Alfa F86 I had would go much faster on the same watts as the EPO F86 they now sell same as the Mig 15. On 4S the they go about 100 mph @ 600 watts the alfa kits were over 115 mph on the same watts. If you were to put them next to each other you would see the differences in how they are built.
Joining this thread very late, but just received my Stinger 64 and waiting for Don's RC to send appropriate motor package. Just read this bit about trailing edges. Should anyone wish to thin the trailing edges (particularly for foam) they might consider the following technique. Cut a thin slot in the trailing edge, insert a thin piece of carbon fiber using appropriate glue, sand the trailing edge down to the carbon fiber. Purpose of carbon fiber is to significantly strengthen the material.