Earth spinning

If the treadmill theory worked they'd have them on aircraft carriers. As alluded to above the treadmill is just a rolling road, the plane would have to increase power just to stay on the same position on the treadmill, even if at full power the plane is still staying in the same position on the treadmill but it is stationary in terms of the surrounding air blowing across the wings which provides the lift that an aeroplane requires.

The only way the treadmill theory would work would ne to have a giant fan blowing air at the plane to provide sufficient lift , you could then in theory get the plane to be effectively flying in a stationary position.

Right - well I'm not going to mention it again anyway !
 
SiriusB said:
Sigh.

http://www.airplaneonatreadmill.com/

I vote for a permaban for the next person to bring this topic up again.
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The question on that site is...

" plane is standing on a large treadmill or conveyor belt. The plane moves in one direction, while the conveyor 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?"

And I agree completely. The plane will take off.

What's your point?
 
Skillmister said:
It's not that i don't know it works, it's that my physics knowledge doesnt lead me to believe it can work.
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It works because of magic!

Read the link - it is very informative. It also highlights the stupid arguments and how people argue the wrong thing depending on how the question is asked.
 
neodude said:
So, enlighten me. How does the plane move without the wheels turning at a different speed to the treadmill?
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The treadmill cannot match the speed of the wheels while thrust is being applied by the engines, period. The question has been malformed and you are arguing semantics because somebody failed to type the question correctly and in doing so decided to break the laws of physics.
 
neodude said:
The question on that site is...

" plane is standing on a large treadmill or conveyor belt. The plane moves in one direction, while the conveyor 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?"

And I agree completely. The plane will take off.

What's your point?
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My point is this topic has been done to death and that site has all the info you could want and covers the different forms of the question. It wasn't directed at anyone in particular so wind your neck back in.
 
neodude said:
So, enlighten me. How does the plane move without the wheels turning at a different speed to the treadmill?
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It is not possible. The thrust will always overcome the wheel speed, and the aircraft will move.

If we theoretically change the laws of physics to help your argument, then we can stop the aircraft taking off.
HOWEVER , If you can do that in your world, I can walk through walls..........PROVIDED physics no longer applies to me, of course.
 
Skii said:
If the treadmill theory worked they'd have them on aircraft carriers. As alluded to above the treadmill is just a rolling road, the plane would have to increase power just to stay on the same position on the treadmill, even if at full power the plane is still staying in the same position on the treadmill but it is stationary in terms of the surrounding air blowing across the wings which provides the lift that an aeroplane requires.

The only way the treadmill theory would work would ne to have a giant fan blowing air at the plane to provide sufficient lift , you could then in theory get the plane to be effectively flying in a stationary position.

Right - well I'm not going to mention it again anyway !
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swap the plane for a jumpjet, problem solved.. (or helicopter)
 
Dano said:
The treadmill cannot match the speed of the wheels while thrust is being applied by the engines, period. The question has been malformed and you are arguing semantics because somebody failed to type the question correctly and in doing so decided to break the laws of physics.
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I agree entirely. The question has no basis in reality, and is different to the original "plane on a treadmill" question.

I'm not arguing semantics either.

I simply stated in answer to the question which someone else posted...

"If an aeroplane was sat on a treadmill that was moving in the opposite direction at the same speed the wheels were moving, would it be able to take off?"


...That in that case, no, the plane wouldn't move. If it did the rules of the question are broken.
 
Malt_Vinegar said:
It is not possible. The thrust will always overcome the wheel speed, and the aircraft will move.
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Which breaks the rules of the question asked.

Malt_Vinegar said:
If we theoretically change the laws of physics to help your argument, then we can stop the aircraft taking off.
HOWEVER , If you can do that in your world, I can walk through walls..........PROVIDED physics no longer applies to me, of course.
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It's not an argument. It's a statement of fact. And I agree it has no basis in reality. But the fact remains, if the treadmill is exactly matching the wheelspeed of the plane then the plane can't move a smegging inch.
 
neodude said:
Which breaks the rules of the question asked.



It's not an argument. It's a statement of fact. And I agree it has no basis in reality. But the fact remains, if the treadmill is exactly matching the wheelspeed of the plane then the plane can't move a smegging inch.
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The treadmill will NEVER match the speed of the plane's wheels, the wheels will just spin faster, and the plane continue moving forwards, and then take off.
 
I suppose another way of looking at the aeroplane is to replace the wheels and treadmill with a concrete post of infinite rigidity and strength attaching the plane to the ground.
Or just mount the propellors or jets directly on the ground, and ask if they'd move.
 
neodude said:
In reality, yes.

but in the confines of the question it would be impossible for the plane to move.

I'm happy to agree that the question is stupid and has no basis in reality. Failing that we'll just have to agree to disagree.
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How would it be impossible for the plane to move? As stated in the article, the wheels on the plane are really only there to support the plane, theyre not attached to any kind of drive.. theyre free moving (Aside from slight friction within the bearing itself). Which means, when the engine is turned on and the pilot attempts to take off, he will, as the wheels have no affect on movement of the plane, the thrust from the engines does and therefore moves the plane, regardless of how fast the wheels / treadmil runs.

Have a proper read of that link that was posted.. it explains it a lot better than I can
 
Gonna change my stance on this, the plane would take off.

The plane would only need x amount of thrust to keep it stationary, x being the resistance caused by the bearings and tyre friction regardless of the treadmill speed.

Any thrust greater than x would cause the plane to move forward.

Thats how it's working in my head now that I've thought about it more anyway.
 
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