i've sorta changed my mind, the plane wouldnt be able to start moving, even though it would be thrusting , because it needs friction on the floor to make it move, it USES its wheels to make it move, even though it isnt powered by the wheels. but they are moving. and the plane isn't. so the more thrust you put in to the plane, as it would start to roll the wheels would spin faster but the plane wouldn't move anywhere as the conveyor belt is matching the POWER!!!! think of a kid on a skateboard with rockets under his arms, on a conveyor belt. If the rockets proppel him to go at 30mph but the conveyor belt is going the other way at 30 mph he isnt in theory going newhere, but to him it feels like he is!!!! so he would be gettin no wind in his face = no wind over the wings of a plane/in the engines (whatever) equalling no movement. And the skateboard wheels, like the plane wheels have no engine moving them, it is all to do with the rockets/engines above!!!! i hope this is clear to you all!! joE!