A plane CAN fly off a threadmill *mythbusters*

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Ignition101

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[ame=http://ca.youtube.com/watch?v=YORCk1BN7QY&feature=related]YouTube - Mythbusters Plane on Conveyor Belt Ending[/ame]
 
not to start a debate, but the conveyor belt was not traveling at the same speed as the plane or else the plane wouldn't move laterally forward allowing wind to give it lift.

but never-the-less, the plane would be taking off due to it's porpellor (or in some cases, it's engine) and would therefor be moving above the conveyor belt and not cause from it's wheels and would therefor take off.
 
Hey-G said:
not to start a debate, but the conveyor belt was not traveling at the same speed as the plane or else the plane wouldn't move laterally forward allowing wind to give it lift.

but never-the-less, the plane would be taking off due to it's porpellor (or in some cases, it's engine) and would therefor be moving above the conveyor belt and not cause from it's wheels and would therefor take off.
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Don't be anal it fkn took off that's it.
 
There was a huge thread about that already.

The simple truth, the plane doesn't care about being on a conveyor belt or not, the wheels are free-wheeling any way. The propeller (or jet engine) will give the plane the forward speed it needs to generate lift, and once at the proper speed (relative to the air, not the the ground or the belt), the plane will take off.
 
Hey-G said:
not to start a debate, but the conveyor belt was not traveling at the same speed as the plane or else the plane wouldn't move laterally forward allowing wind to give it lift.
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exactly....meaning the belt underneath is useless since the plane, going faster, is rolling on it as if it were regular ground.....

the real test should be if the conveyor belt is going one way, and the plane is thrusting the other way, BUT the plane stays next to the cones....then will it take off? NO. if the plane is allowed to advance then he's like on normal ground.
 
RdKetchup said:
There was a huge thread about that already.

The simple truth, the plane doesn't care about being on a conveyor belt or not, the wheels are free-wheeling any way. The propeller (or jet engine) will give the plane the forward speed it needs to generate lift, and once at the proper speed (relative to the air, not the the ground or the belt), the plane will take off.
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also true...which is why I say that the belt is useless, not to say invisible to the plane....so their not proving it right.
 
scarface2003 said:
exactly....meaning the belt underneath is useless since the plane, going faster, is rolling on it as if it were regular ground.....
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Yep, but the wheels are actually going twice the normal speed.


scarface2003 said:
the real test should be if the conveyor belt is going one way, and the plane is thrusting the other way, BUT the plane stays next to the cones....then will it take off? NO. if the plane is allowed to advance then he's like on normal ground.
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The goal was to prove that a plane running on a threadmill going in the opposite direction (or on a free wheeling threadmill) could take off (given a long enough threadmill), and thats exactly what they've proven.
 
RdKetchup said:
Yep, but the wheels are actually going twice the normal speed.





The goal was to prove that a plane running on a threadmill going in the opposite direction (or on a free wheeling threadmill) could take off (given a long enough threadmill), and thats exactly what they've proven.
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that's where the problem is...if it's a "long enough threadmill", then might as well just call it "the floor".

put it on a threadmill the same size as the plane, and see if it takes off. then you get your real answer.
 
scarface2003 said:
that's where the problem is...if it's a "long enough threadmill", then might as well just call it "the floor".

put it on a threadmill the same size as the plane, and see if it takes off. then you get your real answer.
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It all comes down to the way the problem is presented.

Can a plane take-off on a long enough threadmill? Yes.

Can a plane remaining stationary on a threadmill (in zero wind conditions) take-off? No.
 
RdKetchup said:
It all comes down to the way the problem is presented.

Can a plane take-off on a long enough threadmill? Yes.

Can a plane remaining stationary on a threadmill (in zero wind conditions) take-off? No.
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exactly...but whenever people talk about this myth, they dont mention a long enough threadmill, they just say threadmill....which is exactly what everyone knows it is.

all this testing was a big waste of time lol
 
what happens if the conveyor was travelling in the same direction as the place? this is what jumps out at me.
 
mk2-1jz said:
what happens if the conveyor was travelling in the same direction as the place? this is what jumps out at me.
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Nothing special. The plane accelerate slightly faster than usual (probably not measurable) due to not having to fight friction within the wheels, and take off at it's usual speed, except the wheels would not be turning at all.
 
I didnt read the other posts so someone probably already said it but anyways...
They so didnt understand the myth... I cant beleive it... the plane is moving.... the myth is if the plane reach the speed it need to start flying while he's not moving (because the plane is on a threadmill) will it be able to start flying.... and the answer is no, I'm 100% sure.
 
The other threads about this subject we're:

"Can a plane take off on a threadmill?"

and every one was answering no, that's why I posted this video, even tho I'm still no convinced because like some of you said the threadmill wasnt going at the same speed as the plane....
 
Guys, you're missing the general concept here. The conveyor belt doesn't matter. The only thing that it will do is make the tires spin faster. The plane is pulling against the air, not the pavement. Its propulsion comes from the propeller, not the tires.

Get your roller blades (perfect physics rollerblades...no friction in the wheel bearings) and go over to the gym. Put on the skates and hop on a level treadmill. Turn on the treadmill.

No matter how fast the treadmill is spinning, you won't go anywhere - the wheels spin at the same speed as the treadmill surface and you stay at 0mph with respect to the fixed floor.

In other words, it's EXACTLY like you were standing on a smooth, frictionless surface. Play with the treadmill speed all that you want, it makes no difference, you don't move. There is NO FORCE causing you to move backward. Set the treadmill to 1mph or 100mph, you don't go anywhere, even though the skate wheels will be spinning like mad.

Now let's apply some forward thrust. Your buddy comes up behind you, standing on the floor, and starts to shove you forward. You begin to move up the treadmill at exactly the speed he is pushing. If he pushes you at 1mph, you move at 1mph, even though you've got the treadmill moving at 100mph.

And that's exactly what happens with the airplane on the conveyor belt - it's just a plane on a frictionless runway. The jet engine provides thrust which causes forward motion regardless of how slippery the runway is. The wheels can revolve at 1mph, 100mph or 1000mph, it makes no difference at all.

Add friction... simply means that you need a little bit more trust, to overcome the energy transfered to friction, that's all.
 
chicito said:
Guys, you're missing the general concept here. The conveyor belt doesn't matter. The only thing that it will do is make the tires spin faster. The plane is pulling against the air, not the pavement. Its propulsion comes from the propeller, not the tires.

Get your roller blades (perfect physics rollerblades...no friction in the wheel bearings) and go over to the gym. Put on the skates and hop on a level treadmill. Turn on the treadmill.

No matter how fast the treadmill is spinning, you won't go anywhere - the wheels spin at the same speed as the treadmill surface and you stay at 0mph with respect to the fixed floor.

In other words, it's EXACTLY like you were standing on a smooth, frictionless surface. Play with the treadmill speed all that you want, it makes no difference, you don't move. There is NO FORCE causing you to move backward. Set the treadmill to 1mph or 100mph, you don't go anywhere, even though the skate wheels will be spinning like mad.

Now let's apply some forward thrust. Your buddy comes up behind you, standing on the floor, and starts to shove you forward. You begin to move up the treadmill at exactly the speed he is pushing. If he pushes you at 1mph, you move at 1mph, even though you've got the treadmill moving at 100mph.

And that's exactly what happens with the airplane on the conveyor belt - it's just a plane on a frictionless runway. The jet engine provides thrust which causes forward motion regardless of how slippery the runway is. The wheels can revolve at 1mph, 100mph or 1000mph, it makes no difference at all.

Add friction... simply means that you need a little bit more trust, to overcome the energy transfered to friction, that's all.
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Yes you are right, but I just taught about something, this experience was made with a front rotator plane, what about a boieng, is it the same thing or it's different because of the different engine mecanism?
 
Ignition101 said:
Yes you are right, but I just taught about something, this experience was made with a front rotator plane, what about a boieng, is it the same thing or it's different because of the different engine mecanism?
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Same concept, the reactors will be pushing the plane forward. Like the guy said, the wheels will spin the same speed the threadmill goes, no matter how fast it goes if the plane stays immobile. Now whether you add propellers, reactors etc, it'll be the same; plane will go forward as if there was no threadmill under it
 
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