Make sure to use an anchor such as a soft rope tied to a post and the other end to the horizontal stabs to keep the plane from jumping forward before you run the engine. For break in follow the instructions. The engine is a non ring type which means that you don't break it in while running too rich or you will have lots of problems. I found that the OS engines run very stable after the 3d tank so I so like to burn 3 full tanks through a new engine before I let it pull the plane into the air.