as i said before.......it would be abit easier to answer if we new all the facts, although dont think it would help people as they actually know the answer already!!! i cant answer this question as im unsure what would happen due to not knowing weight of plane (although we could take a normal planes weight)........speed of the convetor belt, size, thickness of belt!! size of engines and bhp?? oncoming airspeed! air temp! are the tyres pumped up............... what!!! or maybe none of it!!!!!
imo...if the belt was moving slowly (i think) the plane would move back!!