Will a plane take off from a backwards moving treadmill?

Roger Wilco said:
A most ingenious paradox. But it serves only as a misdirection ploy that distracts us from the simple fact that the speeds of the treadmill/conveyor belt and wheels are totally irrelevant.
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I would say "nearly" irrelevant, because even if we assume perfect wheel bearings, there will be some increase in the rolling resistance of the tires.
 
Baked Potato said:
The paradox in the viral example is that the treadmill can exactly match the speed of the wheels. If that's the case, how can the wheels move forward? It creates an infinite feedback loop since an airplane will move forward on a treadmill when thrust is applied.
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That is why it is poorly-worded. What it proposes, is not possible. No matter how fast the treadmill turns, it can not prevent the airplane from moving forward if it is producing enough thrust to overcome drag.

If we are going to ignore the laws of physics in the premise, what laws of physics should we also ignore in deducing the answer?
 
Palmpilot said:
I would say "nearly" irrelevant, because even if we assume perfect wheel bearings, there will be some increase in the rolling resistance of the tires.
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Yes, if we were actually planning to build real airplanes that would really takeoff from real conveyor belts. Which we aren’t.
 
Palmpilot said:
I would say "nearly" irrelevant, because even if we assume perfect wheel bearings, there will be some increase in the rolling resistance of the tires.
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Rolling resistance is nearly constant with speed. So close to constant, at least, that they generally assume it to be constant for most calculations. Aerodynamic drag, of course, increases with the square of velocity and the airplane doesn't have any trouble overcoming that. This is why the treadmill has no ability to prevent the airplane from moving forward, no matter how fast it goes.
 
Oh, wait, wait. I just reread to the topic. What exactly is a "backwards moving treadmill".

I mean, if the entire treadmill is being pulled backwards and actively moving the plane backwards, then it's not taking off. The only way the plane can make forward motion is to leave the treadmill. At that point is it no longer "on a treadmill" at all and any notion of the propellor's forward thrust overcoming the treadmill becomes irrelevant.
 
When you apply the toe brakes on an airplane mounted on a treadmill rotating at 60 miles an hour, you WILL fly backwards!
 
Well if anyone is going to try this, remember to weld the differential carrier together, or you risk getting all the thrust on one side and flying off the side of the runway. Unless you're flying a Mooney, pretty sure they have a locking diff.

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