Hey chopper man,I 've got an OS55AX with a APC 10x7 four blade prop on mine and it screams.I also have a Mac's muffler on it.I had the prop laying around,and I needed ground clearance,so I used it.I put mine together as a taildragger,and the gear I had on hand were short hence the ground clearance problem.The only problem I see with this airplane is now I want a bigger one,so I'm going to order a 60 size from Bluejay Airplanes.Have fun and good luck with your's.


Jim