Originally Posted by JeremyBB
Second trial today in much calmer conditions. With no forward or reverse thrust, the craft rotates clockwise quite rapidly almost on its own axis
. How can I trim it to stop this happening? It makes control very difficult. I have added perspex extensions to the rudders which now work better but still cannot overcome the rotation problem. I dare not go out on open water until I can correct this. Help please!
Suspect you may have a torque issue possibly? On the full size craft there are four puffer doors, two forward and two aft, that dump plenum air via door on the top skirt shell. Served two purposes, firstly to provide low speed thrust to control the craft, and to allow you to dump air on the inboard side on a high speed turn. Also I note that your skirt does not have a keel. The full sized craft had a keel bag running form roughly a third from the front to the twin rear bags, and there was also a single bag from port to starboard ahead of the keel bag. The keel bag did drag in the water.
Just a comment, and a nice model by the way