Can a plane take off on a tread mill?

broncosbybart said:
this is correct. lift is created by air passing across the wing surface. the airspeed of the aircraft would be 0. it would be like flying at 50 knots with a 50 knot tailwind. the only direction you would go is down. this is why you always take off and land INTO the wind.
you could think of it like this- if an aircraft carrier was used to do the same thing, (say at 30 knots), the plane moves forward relative to the carrier at 30 knots. as soon as it leaves the end of the ship, it's airspeed is still 0. the plane wheels will be turning. heck, they'll still be turning when it hits the ocean...
though i didn't watch whatever happened on myth busters, it is possible that if they had a very light plane with a prop on the nose, it might create enough wind to create some lift. that being said, my first answer is what i will stick with. good night.
edit, just saw the video. the plane was very light and was in fact moving forward when it took off. watch how the traffic cones are passing by at a good clip.
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100% wrong.
 
rockcity said:
Yes it will, it just means the tires are spinning twice as fast as the plane is moving
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This is all anyone needs to know.

Plane on a treadmill. Plane attempts to take off, treadmill runs the other way.

What happens: Plane moves forward, just like it would if it was on solid ground, and takes off.
Wheels spin a lot faster, due to treadmill running backwards.

Treadmill will not cause the plane to stay still, just causes the wheels to spin faster.
 
BigRedB2 said:
thats stupid if the plane gets to move forward. who cars.
i wanna see a plane powerfull enough to take off from a treadmill and no forward momentum.
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That won't happen. The plane will still move forward, regardless of how fast the treadmill is running. But the plane's wheels will move faster, which has nothing to do with how fast the plane is moving.
 
Pacfanweb said:
That won't happen. The plane will still move forward, regardless of how fast the treadmill is running. But the plane's wheels will move faster, which has nothing to do with how fast the plane is moving.
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not necesarily. at some point, you can have enough horsepower for the plane to literally pull itself off the ground.

but it would take a treadmill, and some sort of anchor so the plane in fact does not make forward progress before taking off.


an osprey is the only plane that even comes close, and even that is still cheating.

actually....if you think about it...who says the plane has to be on a flat surface...why cant the treadmill be pointed up a wall. with enough horsepower (more then you can reasonably fit in a plane probably) you could do it.
 
BigRedB2 said:
not necesarily. at some point, you can have enough horsepower for the plane to literally pull itself off the ground.
but it would take a treadmill, and some sort of anchor so the plane in fact does not make forward progress before taking off.
an osprey is the only plane that even comes close, and even that is still cheating.
actually....if you think about it...who says the plane has to be on a flat surface...why cant the treadmill be pointed up a wall. with enough horsepower (more then you can reasonably fit in a plane probably) you could do it.
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planes work by air moving over the wings. The top of the wing is arched and the bottom is flat. As the wing travels through the air, it creates lift. More pressure on the bottom of the wing as on the top. The faster it moves, the more lift.

The propeller is there to propel the plane forward, not create lift (unless its a helicopter). If you wanted the propeller to create enough wind to pass over the wings to create lift, that'll be an awful lot of propellers or some that are so large that its not even practical.

Once you go to a turbine, the rules all change especially when you start talking about the Harrier Jet
 
rockcity said:
planes work by air moving over the wings. The top of the wing is arched and the bottom is flat. As the wing travels through the air, it creates lift. More pressure on the bottom of the wing as on the top. The faster it moves, the more lift.
The propeller is there to propel the plane forward, not create lift (unless its a helicopter). If you wanted the propeller to create enough wind to pass over the wings to create lift, that'll be an awful lot of propellers or some that are so large that its not even practical.
Once you go to a turbine, the rules all change especially when you start talking about the Harrier Jet
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yes yes...lift..thrust...more airflow under the wing than over....i know the physics.

but....all this makes me wonder how possible it is to create a vertical take off prop plane. can you get enough horsepower into a plane?
 
BigRedB2 said:
yes yes...lift..thrus....more airflow going under the wing than over....i know the physics.
but....all this makes me wonder how possible it is to create a vertical take off prop plane. can you get enough horsepower into a plane?
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Wait...it's the airflow going over the wings that make it fly....right?
Not the airflow under the wings.
 
The plane would NOT take off if it stayed in the same spot relative to the ground. Mythbusters screwed up. They should have had a 100ft plus cable attached to the tail of the plane so it couldn't move forward.
 
BACON

oh yeah and the horse is named Friday.

Real question, Why the fawk would you put your airplane on a treadmill? There are much better places to store it....Now will a plane take off from a flushing toilet bowl, thats WHAT I WANT TO KNOW>
 
drkelly said:
The plane would NOT take off if it stayed in the same spot relative to the ground. Mythbusters screwed up. They should have had a 100ft plus cable attached to the tail of the plane so it couldn't move forward.
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The initial question didnt say the plane had to be anchored did it?

I mean I would think that if the plane was anchored to a cable and not allowed to propell itself forward it, of course it would not take off...

However if it's not anchored, the wheels only function is to reduce friction... doesnt matter if the tread mill is running 100mph or 1000mph in the opposite direction. As long as the wheels/bearings/tires can take it the plane will still move forward and eventurally take off.


You could set a sailboad on wheels on a treadmill and put a box fan behind it and it'll move forward...
 
MadAR15 said:
There is an airplane on a very large treadmill, as long as a runway. The treadmill moves backwards (opposite direction from the plane) at the exact same speed the plane is moving forwards. Under these circumstances, could the airplane take off?
I say no.
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No, because the plane needs to build speed as forward momentum as the engine spools up. Look at air craft carriers. They hold the plane until the engines spool up and then release it at full speed.
 
Dad worked in USAF / flight control / various stuff in 'Nam and one day he was out working on the tarmac and noticed a huge (C-130 / I am not up on my planes) plane turning onto the runway, but the tower had screwed up.

Just behind him (not sure of the distance) was a light scout type plane, propellers, etc) that had already been cleared for that runway and taxied up into place.

What happened was the big plane did the standard, lock your brakes, spool up the engines and then let go / head down the runway, creating a HUGE volume of air going backwards at the little plane.

This had happened before where jeeps and such were behind the jets and they got blown end over end by the jet engines!

But the pilot of the scout plane was smart/fast / GOOD enough that as the big plane revved up and started generating the airflow, he revved up HIS motor to keep him in place! The LIFT from the airflow put him in the air "hovering" in place, "flying" like mad without moving fwd at all.

As the big plane let off the brakes, moving fwd and the air flow slowed down the scout plane pilot slowly spooled down HIS engine speed too and came back to rest on the ground in approx the same spot!!

So - in the first example if the plane was a JET - NO way the thrust of the engine / if timed with the treadmill means the plane is not moving, therefore NO airflow over the wings therefore zero lift.

If the plane was a prop / I would be skeptical that the prop itself generates enough "air flow" (unless there is also a headwind etc) but I suppose a light enough plane it "could" happen.

Just my 2 cents
 
GubNi said:
No, because the plane needs to build speed as forward momentum as the engine spools up. Look at air craft carriers. They hold the plane until the engines spool up and then release it at full speed.
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There is also a "catapult" system that yanks the plane fwd quickly enough to generate airflow over the wings. A fully spooled engine that is held in place still only accelerates at a certain rate and is not enough to get the needed lift in that short of a runway. Think about a space shuttle lift off, the first few seconds the vehicle hardly moves at all and then it starts accelerating to orbit speed.

WWII aircraft carriers had to be going INTO the wind, etc etc for their planes to have enough lift (no catapults back then) It took them forever to come up with the right combo, have read a bit of history on the guys that "figured" it all out.

Sam
 
drkelly said:
The plane would NOT take off if it stayed in the same spot relative to the ground. Mythbusters screwed up. They should have had a 100ft plus cable attached to the tail of the plane so it couldn't move forward.
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Um, no plane chained to the ground would move.
 
SHINTON said:
There is also a "catapult" system that yanks the plane fwd quickly enough to generate airflow over the wings. A fully spooled engine that is held in place still only accelerates at a certain rate and is not enough to get the needed lift in that short of a runway. Think about a space shuttle lift off, the first few seconds the vehicle hardly moves at all and then it starts accelerating to orbit speed.

WWII aircraft carriers had to be going INTO the wind, etc etc for their planes to have enough lift (no catapults back then) It took them forever to come up with the right combo, have read a bit of history on the guys that "figured" it all out.

Sam
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Carriers still launch into the wind, even with catapults. Add the wind speed to the approximately 33knots the carrier can make, and that's quite a breeze to help with take off.
 
GubNi said:
No, because the plane needs to build speed as forward momentum as the engine spools up. Look at air craft carriers. They hold the plane until the engines spool up and then release it at full speed.
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Why wouldn't a plane on a treadmill do the same thing?

Spool up the engine to full power with the brakes on and the treadmill off, release brakes and start treadmill simultaneously.

Plane will then move forward and take off, just like if there was no treadmill. Only its wheels will be rolling a lot faster, which is independent to the plane's motion.
 
It just hit me that I wasn't thinking about this right. Of course the fawking plane will take off if it is allowed to move! As said, it doesn't matter if it is on a treadmill going 1mph or 1,000mph. The propellar will pull the plane forward thus generating lift from the wind moving across the wings.
 
I think it would be the same as putting a chain on and hold it place. Crank it to full power, and it would just sit there.
 
You correct. Wheel speed doesn't matter, ground speed matters. Treadmill or not, when the ground spped is high enough to produce enough lift on the wings=flight
 
If anything, the plane will take slightly more runway to take off when it's on a treadmill, as the tires spinning 2x as fast generate more drag, slowing the plane's acceleration.
 
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