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>The question states that the wheel rolling speed will never be more than or less than the conveyer belt speed, and so the plane will not move anywhere.
I get what you're saying. As the plane accelerates the wheels will move faster. The conveyor moves in the opposite direction the same as the wheel speed. This means that at any given point the wheels and conveyor would be moving twice as fast as the plane is moving forward. This is all irrelevant because the conveyor still has no ability to stop the plane from accelerating since the plane is putting a force against the air and not the conveyor. Assuming the wheels and conveyor belt don't explode from spinning at twice the speed of the plane the plane will take off like normal.
Lol
I was expecting to get rickrolled the entire time I watched that.
Read this:
http://mouser.org/log/archives/2006/02/001003.html
And this one is even better:
http://www.illuminatingscience.org/plane-on-a-conveyor-belt/
>The lift force which an aircraft needs to take off is as a result of air flowing over the wings.
Right, so the plane needs to move forward relative to an observer on the ground and take off when their is sufficient airflow over the wings. We get that.
>If an aircraft is on a conveyor belt which means it is stationary with respect to an observer standing watching on a patch of grass next to the conveyor belt then the aircraft is also stationary with respect to the air around it. The air will not flow over the wings and therefore there will be no lift and no take off.
Wrong. The conveyor belt doesn't effect the plane because the thrust from the engines isn't being transferred to the ground. What do planes engines push against? It's not the ground. At 35,000 ft there's no ground for the planes engines to push against. Therefor even though the conveyor is moving at the exact opposite speed of the plane, the plane will still move forward relative to the observer because it doesn't rely on it's tires to propel it forward.
>With the tree example, it is staying in one place, as well as the air around it.
The air around the plane would be the same, there wont be any lift for the plane and no take off.
And IF it did lift off, which it wont, the plane would be in stall and would come crashing down anyways..
The plane will push against the air and move forward relative to the tree and will take off close to it's normall takeoff distance [relative] to the tree. The conveyor isn't holding the plane back since the plane is pushing against the air and not the conveyor.
The wheels and the conveyor can spin as fast or as slow at they want. The wheels buffer the plane from the conveyor. The plane will still accelerate relative to the stationary air.
You're just not thinking hard enough.
I gave up. Think about it until you get it.
I give up. You are stupid. the wheels support the plane. The plane does not drive like a car. The wheels are free spinning. The engines/props move a plane.
>i agree, but that wasnt the question. "Imagine a 747 is sitting on a conveyor belt, as wide and long as a runway. The conveyor belt is designed to exactly match the speed of the wheels, moving in the opposite direction. Can the plane take off?" read the OP, NOOB
Damn it I'm too far into this to stop being trolled. It will take off because a 747 doesn't move by by turning it's wheels. It moves by pushing air. The conveyor could be going thousands of knots faster then the plane could ever go but as long as the air is stationary the plane will move forward relative to the ground next to the conveyor and take off in it's normal takeoff distance. Assuming the wheels don't explode from going that fast that is.
Avo, Shut it troll.
Say we have two objects. A long (like the size of a runway) conveyor moving at the planes max speed and a stationary tree next to the conveyor.
Now how do planes work? Do they turn their wheels or do they create thrust by pushing air against air?
On a conveyor at the planes max speed the plane will turn on it's engines and push against the stationary air. No matter how fast it's wheels are spinning it will move forward relative to the tree. It will take off in it's normal takeoff distance relative to the tree no matter how fast the conveyor is moving. The planes wheels are free moving. By the time the plane takes off the wheels will be spinning twice as fast as the speed of the plane but the plan doesn't move forward by depending on the traction of the wheels. It moves forward by pushing the air which unlike the conveyor is not moving.
>If you take a look at that graph you'll see lift is totally dependant on AIRSPEED. Lift is the force on the aircraft used to overcome the aircrafts mass and take it off off the ground. If the aircraft is on a conveyer belt, and is not going anywhere, no lift is generated. If the thrust produced by the aircraft matches say a conveyer belt speed of 100mph, it is still not going anywhere, and still no lift is produced.
A plane on a conveyor gains speed relative to the air. The air around the conveyor is stationary. The plane still pushes against the stationary air to accelerate just the same.
>there was never a question if a plane can take off from a conveyor. because the conveyor could be going a fraction of a mile per hour and it would be cake. the question is if the conveyor matched the wheel speed, so that the plane would be stationary, if it could take off. and when the plane is moving forward while still ont he ground, it shows that the conveyor isnt matching the wheel speed, so the experiment is void, its no more impressive then taking off from a conveyor moving at a fraction of a mile per hour.
Regardless of conveyor speed, a plane will always take off assuming the wheels are perfectly balanced because a plane pushes against air not ground. A plane is on a conveyor. The conveyor is moving at take off speed. The planes engines are off. Plane turns engines on and moves air. Plane accelerates and takes off despite the conveyor because it's engines are not pushing on the conveyor. It's engines are pushing on the air which is not moving.
Nothing's happened. Mods are too busy to right the story.
>the question is if it can be airborne while stationary, not if an airplane's engine is powerful enough to overcome the friction of the wheels.
The question is can a plane take off from a conveyor 
The treadmill moves the wheels at whatever speed it wants. The conveyor still matches the speed of the wheel. The plane pushes air against air to move. It doesn't push against the ground. Thus a plane can take off on a conveyor . . .
>if the wheels arent going faster then the treadmill, then the plane is stationary
The planes wheels are free. Their friction is close to fixed. Once the thrust overcomes that friction the plane takes off regardless of the conveyor's speed.
And that boom is awesome!
http://www.youtube.com/watch?v=4owlyCOzDiE
posted in the wrong thread X(
Read the answer to this guys question. It's below the advertisements
http://en.allexperts.com/q/Physics-1358/Plane-conveyor.htm
Is a heterosexual 6 days a week.
They still move independent of their wheels.
Yes it would take off. 747's engine move air. They don't turn wheels. The engines force air over the wings while the wheels are just free spinning. You'd still get lift.
nope forget that, changing lynch vote to Arnor
Changing lynch vote to DYT.
Posts found: 1,751 to 1,775 of 2,301