T Nation

Will Treadmill Plane Take Off?


The answer is obvious IMO, but I want to laugh at anyone that doesn’t get it.

Hahahahaha, on another forum I freuent there was a humongous 57 page thread on this that lasted almost an entire year.

[quote]JoeG254 wrote:
Hahahahaha, on another forum I frequent there was a humongous 57 page thread on this that lasted almost an entire year.[/quote]

Unbelievable.

Is there some underlying internet joke that I’m missing, or is this a literal question as to whether a plane would become airborne if you were to move the ground out from beneath it, rather than push it forward through the air?

[quote]JoeG254 wrote:
Hahahahaha, on another forum I freuent there was a humongous 57 page thread on this that lasted almost an entire year.[/quote]

tell me you’re not talking about letsrun.com

lmfao at this shit

[quote]Bauer97 wrote:
Is there some underlying internet joke that I’m missing, or is this a literal question as to whether a plane would become airborne if you were to move the ground out from beneath it, rather than push it forward through the air?[/quote]

There are several variations of this question. The LEAST ludicrous version is that the treadmill moves in the opposite direction at the speed that the airplane takes off at. Will it take off?

Another variation is the more ludicrous version…

A plane is standing on a runway that can move (like a giant conveyor belt). This conveyor has a control system that tracks the plane’s speed and tunes the speed of the conveyor to be exactly the same (but in the opposite direction).

Will the plane be able to take off?

This question is ludicrous because of the assumptions involved.

Side View…

[quote]belligerent wrote:
JoeG254 wrote:
Hahahahaha, on another forum I freuent there was a humongous 57 page thread on this that lasted almost an entire year.

tell me you’re not talking about letsrun.com

lmfao at this shit[/quote]

I found the thread I was talking about.

http://3dgamenight.com/forums/m_146438/mpage_1/tm.htm

Really insane how bad that thread got.

Mythbusters did a segment on this one. I can’t believe that people have such a hard time with this.

[quote]SkyzykS wrote:
Mythbusters did a segment on this one. I can’t believe that people have such a hard time with this.
[/quote]

It is because of the second, more ludicrous version of the question that proposes that the treadmill somehow “keep up with the speed of the plane.” It’s nonsense.

Why would anyone even think it would? I don’t get it at all.

oh oh I know this one! The treadmill will rip the planes wings off and so OF COURSE it will fly! …no wait…

Those people must be afraid that the pilot might hit the wheel brakes in flight.

[quote]Zap Branigan wrote:
Why would anyone even think it would? I don’t get it at all.[/quote]

If you read my other post, in scenario #1 the wheels would simply spin at twice the speed that the plane needs to take off because the thrust comes from the prop/jet and not the wheels. It would take off just fine.

Scenario #2 is nonsense.

[quote]CrewPierce wrote:
oh oh I know this one! The treadmill will rip the planes wings off and so OF COURSE it will fly! …no wait…[/quote]

That was my first thought. Even if it could leave the ground, the wings would rip right off.

Silly question.

[quote]SkyzykS wrote:
Mythbusters did a segment on this one. I can’t believe that people have such a hard time with this.
[/quote]

I just googled it but I cannot watch the video. Did they achieve forward motion with the plane to make it take off?

If so that isn’t the question as I understand it.

[quote]beebuddy wrote:
Zap Branigan wrote:
Why would anyone even think it would? I don’t get it at all.

If you read my other post, in scenario #1 the wheels would simply spin at twice the speed that the plane needs to take off because the thrust comes from the prop/jet and not the wheels. It would take off just fine.

Scenario #2 is nonsense.[/quote]

I was only considering scenario 2. The whole thing is nonsense.

Can a plane overcome a negative force and take off? Yes.

Can a plane remain motionless relative to the ground and atmosphere (like a runner on a treadmill) and take off? No.

How can it take off not moving through the air? It would be stationary, and don’t you have to move through the air to produce lift?

[quote]Zap Branigan wrote:
beebuddy wrote:
Zap Branigan wrote:
Why would anyone even think it would? I don’t get it at all.

If you read my other post, in scenario #1 the wheels would simply spin at twice the speed that the plane needs to take off because the thrust comes from the prop/jet and not the wheels. It would take off just fine.

Scenario #2 is nonsense.

I was only considering scenario 2. The whole thing is nonsense.

Can a plane overcome a negative force and take off? Yes.

Can a plane remain motionless relative to the ground and atmosphere (like a runner on a treadmill) and take off? No.[/quote]

What would actually happen in scenario #2 would be something like the speed of the treadmill increasing exponentially until the wheel bearings blew. It would probably happen almost instantly, but the plane would move forward slightly in that split second and then look like the plane in the pic.

[photo]14296[/photo]

Well, maybe not exponentially but the treadmill would have to be able to achieve the same speed as a plane in flight, which the bearings probably wouldn’t bear.

[quote]Zap Branigan wrote:
beebuddy wrote:
Zap Branigan wrote:
Why would anyone even think it would? I don’t get it at all.

If you read my other post, in scenario #1 the wheels would simply spin at twice the speed that the plane needs to take off because the thrust comes from the prop/jet and not the wheels. It would take off just fine.

Scenario #2 is nonsense.

I was only considering scenario 2. The whole thing is nonsense.

Can a plane overcome a negative force and take off? Yes.

Can a plane remain motionless relative to the ground and atmosphere (like a runner on a treadmill) and take off? No.[/quote]

Draw a free body diagram of an airplane on a treadmill. Consider that the engines move the plane in relation to the atmosphere, not the ground, and you will see that the only force acting against the plane from the running treadmill is the friction in the wheel bearings. There is no connection between the engine propulsion and the wheel speed. The plane takes off, the wheels just spin twice as fast. Of course, the tires are not rated for that type of wheel speed and would probably explode, but we’ll say they don’t.