Think, people. Think. It’s not that difficult. Of course the plane is gonna fly because the prop is moving it through the air. As the plane moves through the air, air flows over the wing surfaces and creates lift. So it flies. It doesn’t matter a whit if the conveyor belt is moving forward or backward under the plane; as long as the wheels allow the plane to roll freely, the prop will move it through the air and create lift.

As fun as this is, I’m tired and I’m going to bed. See you tomorrow.

But I’m going to make one point in particular on this, and let the age-old descussion of the fact that the weeld dont make a lick of diffrence to the physicist. To the people that keep saying this has anything to do with “the propeller being able to pull enough air over the wings to make it take off” are missing the point. That’s not what the issue is. The issue is relativity, inertia of the wheels, and friction.

I can say no, infact NO PLANE EVER MADE has enough raw thrust the propeller can push enough air across the wings to make it take off with no motion to the relative air. I personally fly a Cessna 172 w/180 HP engine swap, and on a “short field” takoff I lock the wheels and put the throttle all way way in to get ready for takoff. Does the place create any relative lift when this happens? NO. The additional airflow across the wings in this case might produce 50 lb of lift at most, and maybe another 25lb in the tail. Walter

Also, water is a HIGH FRICTION SUFFICE compared to wheels on a runway for airplanes. Your general seaplane can get off the ground in ~500 feet on a runway where it take half a mile on water. Landing takes longer due to the fact that breaks arn’t avalialbe after air-resistance (and also water resistance) becomes a factor.

I know that it would not work because of the reasons you laid out. I didn’t really claim that it would work, I knew it would be a failure because obviously the propeller doesn’t move that much air, just enough to start moving the airplane forward. The problem is that the perception from the MythBusters hosts was making it seem like the wind behind the propeller was enough wind to move over the wings to produce enough lift to take off. Which is of course ridiculous.

MythBusters simply proved a different point, that airplanes can move over frictionless surfaces, which has been known since sea planes and ice planes were invented.

The same process that pushes an airborne plane through the air pushes a grounded plane along the surface of the ground. The wheels, like someone said, are there to reduce or provide friction as needed. (Providing friction when the brakes are applied to increase the plane’s deceleration.) There is no treadmill that can hold a plane in place — the closest analogue would be a bit of ground that raced along underneath the plane, so the plane didn’t move relative to the ground. It would still be moving relative to the air, however, and it would take off. (Or perhaps – a wind tunnel – where the plane is immobile relative to the ground but the air runs past it at liftoff speeds – the plane would lift off of the ground in those conditions, but it would probably be a bad idea to try to fly in a real-world situation where the wind was blowing fast enough to produce lift. Unless you’re one of those storm-plane people.)

The flaw with Piotr’s experiment is that the propellor or engine are not creating the wind over the wings, they’re moving the plane, which is creating the relative movement of air over the wings.

What gives the airplane lift is its speed relative to the surrounding fluid – air. It’s easiest if you stop thinking about a moving conveyor belt or the speed relative to the ground. Speed through the air is all that matters.

Piotr’s experiment would be useless as pilots do his experiment before every takeoff. We put on the breaks and gun our engines up to full throttle to check various settings and to make sure we’ll have full power before trying to head down the runway. You’ll never see an airplane rise off the ground during this time, however.

In short, the propeller provides the basic thrust to cause the airplane to move through the air, conveyor belt or not.

I’ll go back to watching my “t.v. for fools”; at least its not “American Idol” or “America’s Next Top Model”.