飞机和传送带的问题

国外流行的一道物理题，这里还有这里有很多讨论。

假设有一架飞机，停靠在一个传送带。传送带足够宽、足够长。飞机的滚轮开始滚动，而传送带以同样的速度朝相反方向滑动。那么，这架飞机能起飞吗？
Here's the original problem essentially as it was posed to us: "A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?"

在办公室里不能锻炼身体，那么锻炼一下脑子吧。。。

先看看老外怎么说：

Exactly what I was thinking. I wasnt even thinking about the wheels... just the fact the plane isn't really moving, therefore no lift force provided to make the plane actually go... up! An example would be like sitting on those gym bikes with no wheels. You can peddle as fast as you want, but you wont feel the fresh breeze of that speed. No breeze, no wind... no lift!

Airspeed is the only thing that matters to an airplane. The speed of the wheels has nothing to do with anything. You need air flowing very quickly over the wings and tail to generate lift.The only time an airplane can take off from a very low groundspeed if it was facing into a very strong headwind. Some small planes have been know to hover relative to the ground if they are flying directly into a very strong wind.
。。。。。。

我在想，如果飞机可以起飞，那么是不是机场就不用造那么多跑道了呢，有个200米的传送带就足够了，飞机几乎可以原地起飞！但是现在的问题是由于传送带向相反方向等速运转，飞机轮子产生的摩擦力被抵消，而显然这个飞机不是指直升机，螺旋桨在上，产生的气流向下。一般的民航客机要想平地起飞的话，也许条件必须是引擎产生的动力足够大,大到产生的气压差可以将飞机托起来。

问题又绕回来了，在那种情况下，动力足够大是不是可以产生气压差呢?

要知道光是风大是没有用的，就算在风洞里面，最多也只是能够加快飞机轮子和传送带的速度而已！