A few years ago there was an outlaw field off 35 in Lewisville. Now, I did not persoannly witness this incident, but I have it from a very relable source that a pilot did a split s striaght into a helis rotor...don't think there was a winner, as it was a gas chopper and a balsa plane. From what I understand, the rotor hit the engine, (or vice versa) and then there was mutual disintegration. Or so goes the legend...