Plane on a treadmill poll...

[JennB]

http://www.straightdope.com/columns/060203.html

[joecoolfreak]

Still haven't got it have you? The speed of the plane isn't determained by the wheels and it isn't determained by how fast the propeller is spinning. It is determained by how far it goes in a certain time. Very simple concept. In your senerio, assuming that the plane has good bearings(ie...low resistance)...then the propellors would barely have to work to maintain a stationary position. Just enough to overcome the rolling resistance. As soon as you rev up the engine to take off capacity, the plane will move forward and take off just as it normally would regardless of how fast the treadmill goes because the wheels have a definate amount of friction and it doesn't matter how fast they are going.

[joecoolfreak]

http://www.straightdope.com/columns/060203.html

Thank you Jenn
States everything that has already been said and the bottom line...the plane takes off.

[{X}Echo419]

Still haven't got it have you? The speed of the plane isn't determained by the wheels and it isn't determained by how fast the propeller is spinning. It is determained by how far it goes in a certain time. Very simple concept. In your senerio, assuming that the plane has good bearings(ie...low resistance)...then the propellors would barely have to work to maintain a stationary position. Just enough to overcome the rolling resistance. As soon as you rev up the engine to take off capacity, the plane will move forward and take off just as it normally would regardless of how fast the treadmill goes because the wheels have a definate amount of friction and it doesn't matter how fast they are going.

are you reading?

OF COURSE THE PLANE IS NOT PROPELLED FORWARD BY IT'S WHEELS!

take the wheels off and put the plane on the ground. now fly it hot shot.

[joecoolfreak]

this is correct! DRAG makes a plane fly! the wind traveling over the wings creates "DRAG". without it the plane will not take off.
think about it. are the wheels on the plane powered at all? no.
put a FAT A$$ fan in front of that treadmill(and boy it would have to be big) to simulate the air traveling over the wings and the mutha fooker will rise.
I can't believe some of you actually believe a plane would fly on a treadmill.

And this is where it all started...The question was asked...you said no, the plane won't fly...I say yes it will. The answer...yes it will.

[{X}Echo419]

Thank you Jenn
States everything that has already been said and the bottom line...the plane takes off.

there is NO forward movement. IT'S ON A DAMN CONVAYER BELT!

[{X}Echo419]

And this is where it all started...The question was asked...you said no, the plane won't fly...I say yes it will. The answer...yes it will.

WHAT makes a plane fly? huh? go ahead. lets hear what you "think".
here's some help.
http://www.allstar.fiu.edu/aero/fltmidfly.htm

[JennB]

take the wheels off and put the plane on the ground. now fly it hot shot.

Ok. If there wasn't friction caused by the rough ground that would rip the poor little plane's belly off, the engines would still suck in air and pull it forward.

[joecoolfreak]

there is NO forward movement. IT'S ON A DAMN CONVAYER BELT!

In your mock up senerio....taking a rc plan and putting it on a treadmill at the gym...Assume that you placed the plane on while everything was stopped...put your hand behind the plane and then turn on the treadmill full speed....how hard would you have to "push" the plane to keep it stationary (assuming that the plane had "free motion" wheels on the bottom)?

[joecoolfreak]

WHAT makes a plane fly? huh? go ahead. lets hear what you "think".
here's some help.
http://www.allstar.fiu.edu/aero/fltmidfly.htm

And just for the record...I have actually flown a plane...have you? There is a reason that everyone is disagreeing with you...you don't get it...

[speedminded]

lolol, i'm really going to throw all of you off but how much force do you think you would need to apply to an aircraft to keep it stationary on a treadmill....VERY little. Would you need to push the plane the same speed as the treadmill to keep it stationary...NO. That exact same force will hold the plane from moving, whether the treadmill is going 2mph or 100mph. Try it, put a skate board on a treadmill and hold it with your finger as someone turns the speed up...does it get any harder to hold the skateboard stationary? No. With that said, the minimal force to hold the plane stationary would probably be far less than what it takes to taxi it on a runway...Once the throttle is turned up the plane will move forward and take off no differantly than a stationary runway.

[{X}Echo419]

In your mock up senerio....taking a rc plan and putting it on a treadmill at the gym...Assume that you placed the plane on while everything was stopped...put your hand behind the plane and then turn on the treadmill full speed....how hard would you have to "push" the plane to keep it stationary (assuming that the plane had "free motion" wheels on the bottom)?

not hard at all.

you still haven't been able to tell me how the complete lack of speed(look that up yourself) of the plane makes the plane fly.
LIFT and Drag are considered aerodynamic forces because they exist due to the movement of the aircraft through the air. not it's spinning wheels and spinning propeller going nowhere.

[speedminded]

In your mock up senerio....taking a rc plan and putting it on a treadmill at the gym...Assume that you placed the plane on while everything was stopped...put your hand behind the plane and then turn on the treadmill full speed....how hard would you have to "push" the plane to keep it stationary (assuming that the plane had "free motion" wheels on the bottom)?

damn, you beat me to it.

[speedminded]

not hard at all.

you still haven't been able to tell me how the complete lack of speed(look that up yourself) of the plane makes the plane fly.
LIFT and Drag are considered aerodynamic forces because they exist due to the movement of the aircraft through the air. not it's spinning wheels and spinning propeller going nowhere.

*shakes head* What lack of speed? there is NOTHING to prevent the plane from going forward...ZIP, ZERO, ZILCH.

[joecoolfreak]

Echo...I completely understand that the plane must move through the air to take off. I am not argueing that point at all. The point is that it doesn't matter how fast the conveyer belt moves, the plane will still move forward through the air and take off. It's "speed" is determained by how far it goes in a certain time and therefore must move forward. The fact the "ground" is moving backwards is irrelevant. If it stood stationary then it's speed would be 0 and therefore according to the original question...the belt moves at the speed of the plane, so if the plane is moving at a speed of 0, the the belt isn't moving at all.

[{X}Echo419]

And just for the record...I have actually flown a plane...have you? There is a reason that everyone is disagreeing with you...you don't get it...

did you fly it off a treadmill? ask your instructor about LIFT and Drag. and how MOVEMENT through the air achieve L/D.

yeah, the reason is you people don't damn get it....do ..y..yo...you?

[speedminded]

Echo...I completely understand that the plane must move through the air to take off. I am not argueing that point at all. The point is that it doesn't matter how fast the conveyer belt moves, the plane will still move forward through the air and take off. It's "speed" is determained by how far it goes in a certain time and therefore must move forward. The fact the "ground" is moving backwards is irrelevant. If it stood stationary then it's speed would be 0 and therefore according to the original question...the belt moves at the speed of the plane, so if the plane is moving at a speed of 0, the the belt isn't moving at all.

he thinks the plane on a conveyor would act as a car on a dyno...except one thing, A PLANE IS NOT POWERED BY IT'S WHEELS... PERIOD.

[{X}Echo419]

*shakes head* What lack of speed? there is NOTHING to prevent the plane from going forward...ZIP, ZERO, ZILCH.

yeah there is. the treadmill!

[{X}Echo419]

Echo...I completely understand that the plane must move through the air to take off. I am not argueing that point at all. The point is that it doesn't matter how fast the conveyer belt moves, the plane will still move forward through the air and take off. It's "speed" is determained by how far it goes in a certain time and therefore must move forward. The fact the "ground" is moving backwards is irrelevant. If it stood stationary then it's speed would be 0 and therefore according to the original question...the belt moves at the speed of the plane, so if the plane is moving at a speed of 0, the the belt isn't moving at all.

right so it wouldn't fly @ a zero speed

[Ruiner]

there is NO forward movement. IT'S ON A DAMN CONVAYER BELT!

Put your money where your mouth is.

[joecoolfreak]

he thinks the plane on a conveyor would act as a car on a dyno...except one thing, A PLANE IS NOT POWERED BY IT'S WHEELS... PERIOD.

I know...I give up...I have tried to explain it about 8 different ways and I guess I am just not up to the task. Somewhere in his mind he knows that it takes very little pressure by his hand to hold the plane stationary but can't link that to the fact that his hand is the "propeller" in this case and still gets the whole concept of speed messed up in there.

[speedminded]

did you fly it off a treadmill? ask your instructor about LIFT and Drag. and how MOVEMENT through the air achieve L/D.

yeah, the reason is you people don't damn get it....do ..y..yo...you?

Wrong, you don't get it. The treadmill in no way what so ever will prevent the plane from moving forward.

[Ruiner]

yeah there is. the treadmill!

Umm, the treadmill ONLY makes the wheels spin faster, that's it. You understand that, right?

[{X}Echo419]

he thinks the plane on a conveyor would act as a car on a dyno...except one thing, A PLANE IS NOT POWERED BY IT'S WHEELS... PERIOD.

ummmm, no I don't. the conveyor belt prevents the plane from ataining speed. thus the lift and drag on the plane

[{X}Echo419]

Put your money where your mouth is.

what cha doin' saturday afternoon

[Xan]

not hard at all.

you still haven't been able to tell me how the complete lack of speed(look that up yourself) of the plane makes the plane fly.
LIFT and Drag are considered aerodynamic forces because they exist due to the movement of the aircraft through the air. not it's spinning wheels and spinning propeller going nowhere.

You are looking at this the wrong way. The aircraft doesn't move through the air. Air moves around the aircraft. The wheels aren't providing the thrust, thus ground speed has no bearing in the lift and drag equation. Wind speed provided by the propeller, not the wheels is what lifts an airplane into the air. Of course this only works on prop planes. Jets need ground speed because they are being pushed, not pulled.

[JennB]

I can post more and more of these...

http://txfx.net/2005/12/08/airplane-on-a-conveyor-belt/

http://mouser.org/log/archives/2006/02/001003.html

[{X}Echo419]

Umm, the treadmill ONLY makes the wheels spin faster, that's it. You understand that, right?

ummmm, no I don't. the conveyor belt prevents the plane from ataining speed. thus the lift and drag on the plane

you do understand that in order for lift and drag to occur over the wings the plane must be GOING SOMEWHERE! not just spinning on a treadmill.

[joecoolfreak]

You are looking at this the wrong way. The aircraft doesn't move through the air. Air moves around the aircraft. The wheels aren't providing the thrust, thus ground speed has no bearing in the lift and drag equation. Wind speed provided by the propeller, not the wheels is what lifts an airplane into the air. Of course this only works on prop planes. Jets need ground speed because they are being pushed, not pulled.

You are incorrect sir...the propeller pulls through the air and the jet pushes through the air. The result is the same, the body of mass moves through the air and the air is then moved over the wings. A jet will take off just as easily as a plane.

[Z0_o6]

so if a water plane is taking off against a current that matches its speed it wont take off? same basic principle.

[speedminded]

ummmm, no I don't. the conveyor belt prevents the plane from ataining speed. thus the lift and drag on the plane

LOLOLOLOLOLOL. Do you agree that no matter the speed of the conveyor the force to hold the airplane stationary would be the same? Just like my analogy to hold a skateboard stationary on a treadmill. With that said, and you already agreed the force to hold it stationary is minimal, what happens when you apply more power to the planes engines?

[joecoolfreak]

so if a water plane is taking off against a current that matches its speed it wont take off? same basic principle.

repost

[Big Baller]

Currently there are 16 people that are stupid

[Ruiner]

you do understand that in order for lift and drag to occur over the wings the plane must be GOING SOMEWHERE! not just spinning on a treadmill.

Yes, but if a treadmill can only make the free rolling wheels spin faster, what is to prevent the plane from pushing forward? Nothing. It's so very simple. The answer is right in front of you. If the treadmill only spins the wheels, then the plane will move forward.

[{X}Echo419]

This is a quote from NASA. The Venturi effect is based on Bernelli's theory.

When a gas flows over an object, or when an object moves through a gas, the molecules of the gas are free to move about the object; they are not closely bound to one another as in a solid. Because the molecules move, there is a velocity associated with the gas. Within the gas, the velocity can have very different values at different places near the object. Bernoulli's equation, which was named for Daniel Bernoulli, relates the pressure in a gas to the local velocity; so as the velocity changes around the object, the pressure changes as well. Adding up (integrating) the pressure variation times the area around the entire body determines the aerodynamic force on the body. The lift is the component of the aerodynamic force which is perpendicular to the original flow direction of the gas. The drag is the component of the aerodynamic force which is parallel to the original flow direction of the gas. Now adding up the velocity variation around the object instead of the pressure variation also determines the aerodynamic force. The integrated velocity variation around the object produces a net turning of the gas flow. From Newton's third law of motion, a turning action of the flow will result in a re-action (aerodynamic force) on the object. So both "Bernoulli" and "Newton" are correct. Integrating the effects of either the pressure or the velocity determines the aerodynamic force on an object. We can use equations developed by each of them to determine the magnitude and direction of the aerodynamic force.

Hope that helps. There must be flow/velocity in order for the plane to lift off

[joecoolfreak]

There will be flow and velocity...because the plane will move forward...there is nothing to keep it from moving forward.

[{X}Echo419]

Yes, but if a treadmill can only make the free rolling wheels spin faster, what is to prevent the plane from pushing forward? Nothing. It's so very simple. The answer is right in front of you. If the treadmill only spins the wheels, then the plane will move forward.

there's NO WIND PASSING OVER THE WINGS! it won't fly. NEWTON SAYS SO

[Z0_o6]

even on a treadmill there will be airflow around the wings.

[joecoolfreak]

You are stuck on the wrong concept echo...explain how the treadmill will prevent the plane from moving forward...that will help you

[{X}Echo419]

There will be flow and velocity...because the plane will move forward...there is nothing to keep it from moving forward.

it's not moving forward. it's on a convayer belt. if you stand nest to the convayer belt the plane will remain in the same spot next to you.