Thats a Sox fan for ya. Kidding. I didnt say I didnt like the debatable part, but I was pointing out that it is a debatable question. Yes if the engines are burning, they will propel the plane forward, but the op also says that it is moving at the same rate of speed as the plane, so thus if the engines were burning, the treadmill will be going the same speed ( in theory). i gotta stop reading my econ book. too much thinking.