In my old club in the landfill in San Diego........we used to hold unofficial trainer "pylon" races......engines were limited to what you could shoehorn into your trainer......I was flying, and I know I'm dating myself, an Eaglet 50 with a Royal Signature Series .28 and mini pipe. I'd carbon laminated the spars on the wing and modified it to a bolt on setup......it flew really well until it clipped a pylon and pinwheeled in. I'd never had that much fun before or since! *LOL*