The current push physic uses a ray to check if a fuselage is in position to push, but that is inaccurate, i think a better way is to make it a cone which has it's size proportional to the exhaust flame
Also make distance affect the force applied because the current one doesn't seem to take that into account (idk if that's the case but if im wrong ignore this)
Anyway thanks for your hard work jundroo for bringing us this awesome game
Edit: the current design does use a cone/cylinder for the detection but uses the Center of mass to determine if the push force is applied, which is still inaccurate
Increse throttle and watch the fuel tank on top of the engine