My cousin has worked in flight simulation (or something like that) for 30 years. I will see him tomorrow at our family Christmas party so I will get to the bottom of this.
This really doesn't concern anything special that a pilot or a flight simulator person would have special knowledge on.
Will the plane move forward? Yes! The conveyor does not impede the forward progress of the plane. If the plane moves forward it will take off. We have the answer, everyone knows the correct answer.......
Are elephants flying the plane? If the plane is too heavy it might not fly you know……...Also is the conveyor belt made of wood, because otherwise the plane probably wouldn't work and the blade would become dull. Unless of course it's balsa wood. If I understand this correctly, the plane is made of balsa wood and the conveyor belt is bois'd arc. In that case, the pilot would probably get all his hair cut off.