May 4, 2013

Extra 300 Profile with KFm-4 Airfoil

Recently there has been a revolution within the model aircraft community surrounding the KF airfoil.  One day while surfing the Flite Test site  I ran across an interview that was done with Dick Kline, the inventor of the KF airfoil.  The interview is in the format of a YouTube video, but the video is far less interesting than the audio, I'd recommend just turning it on and letting the audio run.  The audio is fascinating.

After listening to the interview with Dick Kline, I knew I had to try the KF airfoil on a plane.  I was in the process of building a new R\C Powers - Extra 300 profile foamy, so I decided that it would be a good test platform for the KFm-4 airfoil.

I've flown the plane several times now, and I have to say that the airfoil makes a noticeable difference in the performance of the airplane.  The plane in general seems to handle better all around, especially landings, which seem to be better due to less wing rocking tendency at low speed.

Another benefit was the elimination of the carbon fiber spar in the wing, due to the lamination of three pieces of foam to create the stepped airfoil.  The plane does have a few bamboo rods for bracing, but that is all I've used, and so far the wings are still attached...