re: Myth Busters/Can a plane take off on a conveyor belt

If we could really make a treadmill that large, why don't we just turn the plane around and use the treadmill to take off in a shorter distance? I think that is the real answer to the problem.

When does that episode air?

What's the point to mythbusters actually doing this? The original question is one under ideal conditions which won't ever happen in the real world.

Plus, the conveyor belt can't cancel out the rotational velocity of the wheels.

This thread =

Lord: Guards! Make sure the Prince doesn't leave this room until I come and get him.
Guard: Not to leave the room. Even if you come and get him.
Lord: No, no. Until I come and get him.
Guard: Until you come and get him, we're not to enter the room.
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Guard: And you'll come and get him.
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Lord: No, no. Leaving the room.
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Guard: ...Until you or anyone else...
Lord: No, not anyone else. Just me.
Guard: Just you..
Lord: ...get back.
Guard: Get back.
Lord: Right?
Guard: Right. We'll stay here until you get back.
Lord: And make sure he doesn't leave.
Guard: What?
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Guard: The Prince?
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Lord: No, I want you to stay here, and make sure he doesn't leave.
Guard: Oh I see. Right.

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Plus, the conveyor belt can't cancel out the rotational velocity of the wheels.

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That and

1. The rotational velocity of the wheels means nothing

and

2. It would increase the rotational velocity if anything

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Has anybody ever freakin run on a treadmill? It doesn't matter how hard you run you don't feel any air in your face unless it's from the damn fan or AC. I'm surprised nobody thought of this.

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Exactly. I read in a runners' magazine that you have to put the treadmill at an approximately 1% incline in order to simulate "real" running (i.e. outside with wind resistance)

No, I'm on board with you and Powerman. Once I realized the treadmill, at the point of contact, was moving the same direction as the wheel when it goes forward, I understood the riddle.

I think part of the confusion here is the mental image of a tiny treadmill; but for the plane to take off, you'd have to have either a)a runway-length treadmill or b)the ability for the plane to seamlessly drive off the treadmill.

The best way I've heard to visualize it is to imagine you are on rollerblades on the treadmill. You wouldn't go anywhere. Now, grab a rope that is attached to something else and pull yourself, and clearly you will immediately start moving.

Another friend of mine put it this way:

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another way to think of it is to imagine that i am on rollerblades on the treadmill and you are standing behind me off the treadmill pushing me so i dont roll off the back. you wouldnt have to push very hard, and nothing the treadmill could do would stop you from pushing me forward. you cant rewrite the premise so that the treadmill is so fast that it matches your pushing speed. the link between you and the treadmill is so inefficient that you destroy it immediately and push me forward.

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I have a better analogy to use. lets say we have a air boat



you launch the airboat into the mississippi river. the current in the mississippi is 30 miles per hour. tops speed of the airboat is 30 mph. do you think the airboat will just sit in place or do you think it will move forward?

>>Aheadwind that is 10 percent of the takeoff airspeed will
reduce the takeoff distance approximately 19 percent.
However, a tailwind that is 10 percent of the takeoff airspeed
will increase the takeoff distance approximately
21 percent.

lets think about it like this. moving the plane backwards on a conveyer will increase the tailwind speed. off the top a 10% increase adds 20% on the distance needed to takeoff. so if you equal the groundspeed of the airplane you will be putting just as much tailwind speed as the plane is trying to gain in headwind.


It should be interesting to watch.,

the experiment won't work. don't worry about watching the show.