remembr in Tribes 1

Remember in Tribes 1, on the Transport and the Scout, that when you push "w" and "s" the thrusters would rotate. I want a vehicle that sorta does the same thing. By default I want the thruster to be pointing down, but if you push "w" it will rotate the mesh (thrusters) to point backwards (for forward thrust). Currently I can fake it by having 2 different jetnozzle nodes My main concern is having "w" activate the thruster animation. and upon release have the animation reset. Can anyone be so kind as to help me with this task?