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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?

Discuss.

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Not any sort of a paradox at all.. There is no air flow over the wing, of course it won't take off.

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Uhm... no. It would just stand there, revving it's engines. It needs to have air flowing over the wings to take off, and for that it needs to be on a surface either going in the direction it's going, or on a stationary one.

Discuss=fail.

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What if the plane was a Harrier? Couldn't it just take off vertically?

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/me stares at |Brad|'s member title

How clever, you changed your member title from "Village Idiot" to "Custom Member Title".

Edited by -Kajun-
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-Kajun- -think a bit harder about the question instead of being a hot shot..

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Old question is full of fail.

No it wouldn't. Anyone who argues is retarded.

Plane takes off from the displacement of high and low pressure air flows across the wing. With the wheels moving, it does nothing to the air flow (at least not nearly significant for what is needed to take off). Besides, the plane would probably just roll off the treadmill anyways.

If it was powered, it would probably start rolling forward if enough power was supplied. And in that case it'd hit the bars on the treadmill. If those were removed, it would probably fall of the end. If it some how kept rolling, and gained speed, assuming it hit minimum necessary velocity, then yes, it'd take off. But then in that case the treadmill is nothing more than an obstacle that was in the way.

Picolini is now Pico

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it will take off. The friction of the Air moved by the engine of the plane will be greater than the friction of the wheels on the treadmill....regardless of the speed. And the air friction is the only important factor as others have stated on this thread.

Source

More proof.

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Old question is full of fail.

No it wouldn't. Anyone who argues is retarded.

Plane takes off from the displacement of high and low pressure air flows across the wing. With the wheels moving, it does nothing to the air flow (at least not nearly significant for what is needed to take off). Besides, the plane would probably just roll off the treadmill anyways.

If it was powered, it would probably start rolling forward if enough power was supplied. And in that case it'd hit the bars on the treadmill. If those were removed, it would probably fall of the end. If it some how kept rolling, and gained speed, assuming it hit minimum necessary velocity, then yes, it'd take off. But then in that case the treadmill is nothing more than an obstacle that was in the way.

I think the 'treadmill' is an infinite loop runway that continues to move at the same speed as the wheels of the plane. I don't think it is an actually treadmill in this theoretical question.

As said before, you need the air displacement.

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it will take off.  The friction of the Air moved by the engine of the plane will be greater than the friction of the wheels on the treadmill....regardless of the speed.  And the air friction is the only important factor as others have stated on this thread.

Source

More proof.

The fault in that experiment is there was a thing holding the plane in place and once the plane got enough power to defeat the treadmill speed, it would take off, I would like to know what would happen if both treadmill and plane kept constant speed

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but those planes are soo light they could accelerate past 10 miles in little time..

The movement of the plane is nearly the same regardless of the acceleration of the treadmill. It has to do with the ammount of air movement against the wings and body of the plane due to thrust vs. the very little amount of friction the wheels make vs the ground even with the plane attached.

This is a new spin on an old equasion.\

Edit: term discrepency

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Old question is full of fail.

No it wouldn't. Anyone who argues is retarded.

Plane takes off from the displacement of high and low pressure air flows across the wing. With the wheels moving, it does nothing to the air flow (at least not nearly significant for what is needed to take off). Besides, the plane would probably just roll off the treadmill anyways.

If it was powered, it would probably start rolling forward if enough power was supplied. And in that case it'd hit the bars on the treadmill. If those were removed, it would probably fall of the end. If it some how kept rolling, and gained speed, assuming it hit minimum necessary velocity, then yes, it'd take off. But then in that case the treadmill is nothing more than an obstacle that was in the way.

Way to think it would be a real treadmill.

Of course it won't No movement forward. No wind, no lift.

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The Physics of Flight have very little to do with the ground and moving the ground is irrelevant as the method of thrust is already moving the air.

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Yea but there has to be more thrust than drag and when both are equal. No lift.

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HGF, you ceaselessly blow my mind.

Where's Bartleby when you actually NEED him, dmanit?

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if you started from zero, the thrust would have to defeat the backward speed to go physically forward but if the plane kept relative but opposite speed to the treadmill it would get no air to take off.

If you were to say the plane was moving at so and so speed relative to a static object, say 40 mph, and the treadmill was going 40 backwards, the plane would be in motion and only then would it defeat the treadmill speed. I guess it depends on how you measure and compare speed.

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K^2?

The real question is, what's the difference? No one's building a treadmill that big.

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cars and planes don't work the same way. A car's wheels are its means of propulsion--they push the road backwards (relatively speaking), and the car moves forward. In contrast, a plane's wheels aren't motorized; their purpose is to reduce friction during takeoff (and add it, by braking, when landing). What gets a plane moving are its propellers or jet turbines, which shove the air backward and thereby impel the plane forward. What the wheels, conveyor belt, etc, are up to is largely irrelevant. Let me repeat: Once the pilot fires up the engines, the plane moves forward at pretty much the usual speed relative to the ground--and more importantly the air--regardless of how fast the conveyor belt is moving backward. This generates lift on the wings, and the plane takes off. All the conveyor belt does is, as you correctly conclude, make the plane's wheels spin madly.

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This equasion and line of questioning is a joke on the public to test their knowledge. Seriously, the air around the plane is not controled by the treadmill.....the thrust of the engine forces air to move across the wings at a rate greater than its forward momentum....That is why the thing flies. The lift is not simply created by forward momentum at all.

That is what thrust is all about and this experiment is actually older than people are letting on to.

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This equasion and line of questioning is a joke on the public to test their knowledge. Seriously, the air around the plane is not controled by the treadmill.....the thrust of the engine forces air to move across the wings at a rate greater than its forward momentum....That is why the thing flies.

My personal feeling is that the treadmill has nothing to do with it since, as GTA3Rockstar and HolyGrenadeFrenzy said, the thrust is what is important. Wheels are of no effect since they are free moving.

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Wait - so can Bugs Bunny can't pick himself up by his own ears?

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I don't think a plane on a treadmill that is moved by the power of the airplane's wheels will move if there is no air intake to the airplane's engines, making the wings catch the velocity of the turbine and flying.

Think of it this way: if the treadmill adjusts to the speed of the plane, only a great amount of wind could make the plane get the necessary speed to let go of the treadmill regardless the speed of it.

Even though the plane takes off, it will react to the wind like a kite would. It would retract and move back due to the force inflicted. And, only after that happens, it will sustain itself and stabilize itself in the air finally flying with no problem whatsover.

So unless wind traveling at a big speed encounters the airplane's wings, the plane will not fly. Because there is absolutely zero air intake into the plane, while it accelerates and because it's not moving (literally). It's not impossible to pull such a feat, but it's hard to.

 o kwoun tat hay mi teo volien. There is no political solution.
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This equasion and line of questioning is a joke on the public to test their knowledge.  Seriously, the air around the plane is not controled by the treadmill.....the thrust of the engine forces air to move across the wings at a rate greater than its forward momentum....That is why the thing flies.

My personal feeling is that the treadmill has nothing to do with it since, as GTA3Rockstar and HolyGrenadeFrenzy said, the thrust is what is important. Wheels are of no effect since they are free moving.

The real thing that bothers me is why the thing is so net buggy in the first place nd then it becomes apparent why.

Keeping people ignorant and then testing how ignorant is not just a political areana. Geeks and myth busters do it all the time. The hype is part of the show.

The Plane and Treadmill issue was thought out enough to look authentic yet it is a farse that is fooling many people.

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I don't think a plane on a treadmill that is moved by the power of the airplane's wheels will move if there is no air intake to the airplane's engines, making the wings catch the velocity of the turbine and flying.

Think of it this way: if the treadmill adjusts to the speed of the plane, only a great amount of wind could make the plane get the necessary speed to let go of the treadmill regardless the speed of it.

Even though the plane takes off, it will react to the wind like a kite would. It would retract and move back due to the force inflicted. And, only after that happens, it will sustain itself and stabilize itself in the air finally flying with no problem whatsover.

So unless wind traveling at a big speed encounters the airplane's wings, the plane will not fly. Because there is absolutely zero air intake into the plane, while it accelerates and because it's not moving (literally). It's not impossible to pull such a feat, but it's hard to.

You're forgetting that the ground has very little to do with things. The plane would simply shoot off the end of the treadmill - if there was ground, it would continue powering ahead until taking off; if it was a French military experiment on an aircraft carrier, it would splash into the sea. Point is - the treadmill have little to no effect on a plane's ability to take off. Watch the video that HGF posted.

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This equasion and line of questioning is a joke on the public to test their knowledge.  Seriously, the air around the plane is not controled by the treadmill.....the thrust of the engine forces air to move across the wings at a rate greater than its forward momentum....That is why the thing flies.

My personal feeling is that the treadmill has nothing to do with it since, as GTA3Rockstar and HolyGrenadeFrenzy said, the thrust is what is important. Wheels are of no effect since they are free moving.

The real thing that bothers me is why the thing is so net buggy in the first place nd then it becomes apparent why.

Keeping people ignorant and then testing how ignorant is not just a political areana. Geeks and myth busters do it all the time. The hype is part of the show.

The Plane and Treadmill issue was thought out enough to look authentic yet it is a farse that is fooling many people.

The problem I see with the whole theory is that the original question is very vague, so it leaves many possibilities. All the youtube vids i looked at portrayed it differently, so it comes down to what variables we examine and what we want to test. Otherwise, there will be no definite answer.

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Hmm so there is no wind you say? The plane isn't moving, given, but with it running on a treadmill at fullspeed. I'm pretty sure it can take off.

At first I thought otherwise but not I'm not sure.

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Hmm so there is no wind you say? The plane isn't moving, given, but with it running on a treadmill at fullspeed. I'm pretty sure it can take off.

At first I thought otherwise but not I'm not sure.

No sir. You're forgetting that lift is provided by the speed of the wings relative to the air.

COOL video though.

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Hmm so there is no wind you say? The plane isn't moving, given, but with it running on a treadmill at fullspeed. I'm pretty sure it can take off.

At first I thought otherwise but not I'm not sure.

No sir. You're forgetting that lift is provided by the speed of the wings relative to the air.

COOL video though.

So how is this any different? Not hte take off part but moving foraward after lift off

Edited by GTA3Rockstar

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Hmm so there is no wind you say? The plane isn't moving, given, but with it running on a treadmill at fullspeed. I'm pretty sure it can take off.

At first I thought otherwise but not I'm not sure.

No sir. You're forgetting that lift is provided by the speed of the wings relative to the air.

COOL video though.

So how is this any different?

Harrier....vertical thrust...expection to the experiment lol

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The wheels have nothing to do with propulsion. That is the job of the propeller or the jet engine. The only feasible applications of this idea would be to put a plane in an air-tunnel, and slow ramp up either an intake or exhaust to lower and raise the air pressure over and under the wings.

The only thing the conveyor would do is free up some of the energy used from the engines to overcome the friction generated by rolling on the ground, but in the end, the plane uses the air around it to move, not the run-way.

It would have no negative effect.

I have a better question. Why is this question still floating around? It's probably been on these forums two or three times now, and it always come back to this same conclusion.

QUOTE (K^2) ...not only is it legal for you to go around with a concealed penis, it requires absolutely no registration!

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