# Can the plane take off?

## Recommended Posts

Imagine a plane is sitting on a massive conveyor belt, as wide and as long as a runway. The conveyor belt is designed to exactly match the speed of the wheels, moving in the opposite direction. Can the plane take off?

Saw this on another forum, interesting answers.

##### Share on other sites

Only if there is enough air moving under or past the wings to create the appropriate amount of lift and a minimal amount of drag. It doesn't matter how fast the wheels go, because a planes ability to fly is governed by the laws of aerodynamics.

##### Share on other sites

oh thank god the answer has been posted.

If there is airspeed, then yes.

##### Share on other sites
Imagine a plane is sitting on a massive conveyor belt, as wide and as long as a runway. The conveyor belt is designed to exactly match the speed of the wheels, moving in the opposite direction. Can the plane take off?

Saw this on another forum, interesting answers.

Yes; the ground speed is irrelevant. Aircraft do not drive the wheels; They are propelled by the thrusters and lift is dependent on air speed.

##### Share on other sites

Fluid Dynamics 101 man.

##### Share on other sites

I think this was discussed in the chat awhile ago lol. But my answer is still no. I don't think it would be able to take off because if the treadmill moves just as fast as the wheels then it won't move at all. Thus not allowing it to get any airspeed.

Edit: Did some googling and found this. Seems that the way this particular question is worded makes the entire situation impossible. But worded differently it would be possible. If this source is correct of course lol.

##### Share on other sites

depends on the airplane...

If it is a Harrier, then vertical take-off for the win.

##### Share on other sites

Taking the question literal and not taking any other forces into consideration, if the opposing forces are equally strong they cancel each other out. Therefore the plane can't take off. It's as simple as that, physical science.

##### Share on other sites
I think this was discussed in the chat awhile ago lol. But my answer is still no. I don't think it would be able to take off because if the treadmill moves just as fast as the wheels then it won't move at all. Thus not allowing it to get any airspeed.

Edit: Did some googling and found this. Seems that the way this particular question is worded makes the entire situation impossible. But worded differently it would be possible. If this source is correct of course lol.

Yes it was in the chat a few months ago; and that website you linked explains exactly why the plane CAN take-off

##### Share on other sites
Taking the question literal and not taking any other forces into consideration, if the opposing forces are equally strong they cancel each other out. Therefore the plane can't take off. It's as simple as that, physical science.

The question isn't statics and dynamics; but rather fluid mechanics. the airspeed across the wings is what generates lift. The wheels don't have any bearing in the equation; if they did, then a float-plane wouldn't be able to take off against the current of a river.

##### Share on other sites

If the plane is on the conveyor belt, and it does not move from it's original location because of the wheels spinning freely, no lift is created by the winds, because there are no winds.

##### Share on other sites

The thrusters propel the aircraft through the air; not down the runway. The wheels merely hold the Fuselage above the surface of the runway; and thus play no role in the question, the wheels would merely have twice the angular velocity as compared to taking off on a regular runway.