# Thread: Would it take off?

1. Originally Posted by Aborted

Once again, the treadmill would be unable to stop the plane from moving forward, and it would skate right off of it, allowing it to take off elsewhere.
Lift and air are entirely irrelevant.
I think the whole point to this was that it was supposed to lift off using the force of the mill, why else would it be there to begin with.
Please do explain how air and lift is irrelevant, are you talking about this instance or do you mean overall, because I'm sure it's called aerodynamics for a reason.

2. Originally Posted by Anesthetic
I think the whole point to this was that it was supposed to lift off using the force of the mill, why else would it be there to begin with.
Please do explain how air and lift is irrelevant, are you talking about this instance or do you mean overall, because I'm sure it's called aerodynamics for a reason.
No matter how fast a treadmill is, it would never be able to stop a plane from moving forward.
It would hover over it like a puck on an air hockey table.

3 facts:
A) If the plane remains stationary relative to the ground, it will not take off.
B) If the plane moves relative to the ground, it will take off.
C) The treadmill by itself can not get the plane to remain stationary relative to the ground, due to lack of traction.

By extension of that, the plane will indeed eventually take off, though it would take a longer treadmill/conveyor belt.

I said air and lift are irrelevant to the argument, because they are. We all know flight is dependent on
Bernoulli's Principle, so the original question isn't even very valid. The entire debate is more whether a treadmill is capable of retaining a plane's lateral positioning, which it isn't, nor ever will be.

3. Originally Posted by EndRiT

You're making the mistake of thinking that forward motion of the plane is generated from it's wheels. The engines create the lift, regardless of what the wheels are doing, as long as the engines reach enough power to provide take off, I'm pretty sure the plane would take off.
Oh shit that's right. The shape of the wing creates lift. The engine propels it. The only question is, would a relatively stationary object create enough lift to fly off? The angle of attack would probably be different for lift off.

4. Originally Posted by Doc

Yea, that'd be me. That's kinda weird though now that I think about it.
I remembered who I was thinking about, it was @Toxin. That faggot flashed it so many times, fuck. Just random imgur links and you click it.

Originally Posted by Fvzion
EDIT: Put some actual thought into it this time.

If the treadmill is going at the same speed in the opposite direction, that only means that the wheels will be going twice as fast
Incorrect. Wheels -> 200 mp/h, Treadmill <- 200 mp/h, net result = 0

5. Originally Posted by arunforce
The only question is, would a relatively stationary object create enough lift to fly off?
What I've been trying to explain is that it would never be stationary, it's impossible to stop a plane with a treadmill. Planes aren't powered by wheels, so torque and groundforce are irrelevant, so increasing a treadmill to 200 mp/h wouldn't produce nearly enough traction to stop its lateral movement. It's a turbine engine with wing lift, only directed from the ground by wheels. As soon as the engine starts, it will start providing lift, though not immediately enough for take off. Any lift at all though, will reduce the traction on the ground, thereby allowing it to begin moving forward. This added speed provides even more lift, allowing it to raise even further off the ground. Eventually it will take off.

Using a treadmill to stop a plane would be like trying to cage a bird with a picket fence.

6. Originally Posted by arunforce

I remembered who I was thinking about, it was @Toxin. That faggot flashed it so many times, fuck. Just random imgur links and you click it.

Incorrect. Wheels -> 200 mp/h, Treadmill <- 200 mp/h, net result = 0
I never took physics, that's my excuse.

7. Why is everyone arguing when the answer is clearly yes? If the treadmill were to keep up with the speed of the plane then yes, it'd take off, it'd just be the same as having a runway only it's stationary, the plane still covers the same distance at the same speeds, it's just that the ground on which it moves doesn't move with it.

8. Originally Posted by Aborted

What I've been trying to explain is that it would never be stationary, it's impossible to stop a plane with a treadmill.
It'd be like trying to cage a bird with a picket fence.
Here's my mental Free Body Diagram.

Think of a person on a treadmill, running forward. Relative to the Earth (the only thing that matters), they're stationary. Now as a stationary object, you're not going to experience the same amount of air as if you were running on a treadmill was on the back of a pickup truck, going forward. Less airflow creates less lift. You need a certain amount of lift to take off, and the moment the wheels leave the treadmill with enough lift not to stall, that becomes irrelevant. But to create that lift without crashing, the speed and angle of attack will have to be different, because you're not getting enough flow. Would that be enough to compensate for reduced lift? Who knows for sure, it's a simplified problem. I've taken Fluid Mechanics, not exactly the same, but you can treat air as a fluid in subsonic speeds.

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So IMO, you can take off, you just need to go faster at a steeper angle.

9. Originally Posted by Scotia
Why is everyone arguing when the answer is clearly yes? If the treadmill were to keep up with the speed of the plane then yes, it'd take off, it'd just be the same as having a runway only it's stationary, the plane still covers the same distance at the same speeds, it's just that the ground on which it moves doesn't move with it.
The main purpose of this enigma is pretty much to cause controversy rather than find the accurate answer. I've seen this problem before, except it's been given some rules/conditions when I first saw it.

10. I know what you're saying though, I'm just confused over the fact that this mindfuckery thing is placed in relations to a human, as you said.
It's not wheel powered and will depending on friction and what not, lets say it doesn't have any friction, then it would in theory be completely still and not move at all.
Would it lift then.

I would like to blame my lack of knowledge on something but I'm past that.
I was sure that the airplanes where dependent on air, which it is, isn't it?
Urgh.

More interesting question, would a plane fly in vacuum?
No it won't, so lets just throw vacuum in that room and then flight 827 will never go to whatever whimsical location it was going to when it first got out on a treadmill.

11. Originally Posted by Anesthetic
It's not wheel powered and will depending on friction and what not, lets say it doesn't have any friction, then it would in theory be completely still and not move at all.
WELL ACTUALLY.............. The air being expelled out the back creates thrust. If it was in a vacuum, however that'd be correct.

12. Originally Posted by arunforce

WELL ACTUALLY.............. The air being expelled out the back creates thrust. If it was in a vacuum, however that'd be correct.
Obviously, because of aerodynamics.
But we weren't given any specifics, just a picture.

Using the information in the picture with all of your examples with thrust would propel it into the bars of the handle and rip the wings and it would never fly again.

13. Originally Posted by Anesthetic
Obviously, because of aerodynamics.
But we weren't given any specifics, just a picture.

Using the information in the picture with all of your examples with thrust would propel it into the bars of the handle and rip the wings and it would never fly again.
Not because of aerodynamics, because air friction creates thrust. The picture isn't important, the concept is. No point in what-ifying it and over thinking it, the principle is still the same.

14. Originally Posted by arunforce

Not because of aerodynamics, because air friction creates thrust. The picture isn't important, the concept is. No point in what-ifying it and over thinking it, the principle is still the same.
I have a tendency to be literal.
Either way, he didn't give enough information for me.
I just imagined it as it were, frictionlessly being static while the tread is running, therefore not lifting the plane.
Because if that were possible we'd have regular boeing airplanes lifting off straight up.

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