Plane on conveyor belt

[hunto]

A plane is standing on a runway that can move (some sort of band conveyor). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyor has a control system that tracks the plane speed and tunes the speed of the conveyor to be exactly the same (but in the opposite direction). Can the plane take off?

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Depends on the plane, because they have to deal with massive temperature changes you have to use very specific materials to make aircraft tyres, most of them will blow out at not much over the required ground speed to achieve takeoff. Therefore you may well not be able to take off as the tyres won't go fast enough on your rolling road. -SmashiusClay

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Since its a hypothetical question, we presume things like tires won't blowout, etc- the question hinges on lift vs wheel speed vs airspeed, thrust, etc. If the conveyor (hypothetical) were the size of a main JFK runway, length and width, the belt itself would generate enough wind to levitate the plane. But thats an extreme example.
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I think the plane stays on the ground. If the conveyor negates the wheel speed, the plane achieves no forward momentum, therefore no lift under the wings, thus it doesn't take off.

 

[ChaseT.]

I think the plane stays on the ground. If the conveyor negates the wheel speed, the plane achieves no forward momentum, therefore no lift under the wings, thus it doesn't take off.

/Thread

 

[hunto]

cute pic, but do you have a rebuttal?

 

[ChaseT.]

cute pic, but do you have a rebuttal?

I refuse to engage in a battle of wits with an unarmed opponent.

 

[bacon]

Unless it has vertical takeoff capability, the planes stays on the ground.

 

[ChaseT.]

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[BlondeWarrior]

The plane will stay on the ground, since the speed of the plane relative to the air is zero. No lift, no bernoulli effect, no flying.

\thread.

 

[BlondeWarrior]

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That's a BIG treadmill for a very tiny plane. I would not be surprised if the treadmill provided enough air over the wings for the pressure difference for the lift.

 

[ChaseT.]

The plane will stay on the ground, since the speed of the plane relative to the air is zero. No lift, no bernoulli effect, no flying.

\thread.

How do you manage to acquire a degree in physics without understanding basic free body diagrams?

 

[hunto]

That's a BIG treadmill for a very tiny plane. I would not be surprised if the treadmill provided enough air over the wings for the pressure difference for the lift.

If the conveyor (hypothetical) were the size of a main JFK runway, length and width, the belt itself would generate enough wind to levitate the plane.

Thats why I included this. If the belt is big enough relative to the plane, the turbulence generated would lift the plane.

 

[bacon]

I don't have sound. What was the verdict with the video?

 

[hunto]

I don't have sound. What was the verdict with the video?

He's just mad because I proposed he stay a permanent white-belt last night.

 

[BlondeWarrior]

How do you manage to acquire a degree in physics without understanding basic free body diagrams?

I just explained it to you. Read.

 

[hunto]

I just explained it to you. Read.

Tell him BW !!!

Attagirl !

 

[liquid!]

None of this = saying on the ground

 

[BlondeWarrior]

He's just mad because I proposed he stay a permanent white-belt last night.

Yeah, true story.

 

[Donut62]

Jesus Christ people, the engines move the plane relative to the speed of the immediately surrounding atmosphere, not the ground. It's like being on a giant treadmill, tethered to a car driving on still ground. When the car takes off your fucked no matter how fast the mill goes.

 

[SteveR]

Mythbusters Part One and Part Two.

 

[BlondeWarrior]

Also, when the plane lifts off the ground, it lifts off backwards very quickly, proving that there has to be some air from the treadmill blowing on it very hard.

This means that that air is providing the lift.

Real planes continue to move forward. Their backward movement is negligible compared to their forward momentum.

 

[ChaseT.]

I'm glad *MY* high school physics teacher wasn't a mental midget.