If a PLANE is on a TREADMILL will it TAKE OFF? (Large plane, large treadmill) [Pics]

[narcistic]

i'm confused as fuark right now

[Emilos12]

OK, let's squash this discussion.


If the plane has 0 velocity relative to the ground it will not lift, simple as that.

If the plane produces enough force to work against the treadmill (eg if the treadmill moves 100km/hr and the plane still manages to have 100km/hr of forward velocity (relative to the ground) it can lift.

It all depends on how much force the plane produces relative to the treadmill, if the treadmill cancels out the forward force of the plane it will not lift since it doesn't have any air pressure around the wings.

The plane will lift as long as the planes velocity is enough to build up sufficient pressure aound the wings, if the plane has 0 velocity relative to the ground it will not lift as long as the wind isn't strong enough to build sufficient pressure arround the wings, which would not be possible in normal weather conditions.

Of course if there is no air moving across the wings the plane wouldnt fly, which is what you would imagine would happen if the speed of the plane relative to the treadmill is 0 (unless there is a headwind). But the plane would need to produce very little thrust to overcome the friction of the wheels on the treadmill, thereby increasing the speed relative to the treadmill, almost regardless the speed of the treadmill, so in reality it would be easy for a plane to take off on a treadmill.

[wowz]

You're correct but than the plane would accelerate off the treadmill, you would need a treadmill the size of an airstrip. I'm assuming the model in the OP

Ok, so the plane accelerates off the treadmill and will take off. Therefore the treadmill did not keep the plane from taking off.

The plane takes off if the treadmill is the proposed size in the OP or if it is runway length.

[Codo]

No, if we assume the air around the airplane is stationary at 0 m/s, then the plane must move RELATIVE to the ground at 45mph (or whatever). No matter how much thrust is produced, it is travelling at 0 m/s relative to the ground. You're thinking of a scenario where there is equilibrium in all forces (due to free-spinning wheels), and as soon as the thrust is switched on the airplane accelerates off the treadmill. That defeats the whole purpose of this thought experiment, if it accelerates off the treadmill then we're just looking at a normal airplane taking off on a runway which is about 2 m in length. Totally defeats the point.

My friend. MY very good friend. You are misunderstanding something here.

The air around the airplane is stationary. Fine.
The treadmill is moving at 45MPH
the ground is 0mph

Treadmill turns on. BAM. 45mph.
Airplane stays turned off.
Airplane stays 0mph in relation to the ground (0mph) while the treadmill goes 45MPH, because the plane wheels are free spinning.

Airplane engine turns on. the engines GRAB the 0mph air and pulls itself forward until it takes off.

[DdotT]

Ok, so the plane accelerates off the treadmill and will take off. Therefore the treadmill did not keep the plane from taking off.

It cannot take off while on the treadmill unless it is the length of an airstrip

I.e it cannot take off on a treadmill

If it accelerates off the argument is invalid

[IIIWolverineIII]

holy **** you guys.

Listen.

FREE SPINNING WHEELS!!!!!!!!!!!!!!!!!!!!!!!!!

That means you can move the treadmill 25 BILLION MPH and the plane won't move an inch. It would sit there safe and sound while the wheels go ape sh*t!

A car does not have free spinning wheels. A car would have to power it's wheels to go 25 Billion MPH to do what hte plane looks like it's doing.

So if I sat a hot wheels car (free-spinning wheels) on a flat treadmill and turned the speed to 25 billion MPH, it would just stay stationary?

Answer: No. The gravity of the little car will hold the wheels to the treadmill, then the combination of that with friction to the treadmill will send it flying backwards unless there was an outside force counteracting the friction/gravity(weight) combo.

In the airplanes case, the counteracting force would be the engines pushing air behind them. They would have to push enough air to counteract the weight of the plane and the speed of the treadmill.

If the force produced by the engines is greater than that of the weight/speed combo, then the airplane would move forward and fall off the fukking treadmill.

In which case, what was the fuking point of a treadmill in the first place? When you fukers run on a treadmill do you go so fast that you run off the front and keep going? Lol

[curlsbraah]

★★★★★ Thread

[Smithers115]

lol have you retards even watched the Mythbusters episode? or are you so brainless that you just regurgitate whatever another miscers says?



Its real simple, the power comes from THRUST FROM THE JET ENGINES. Not in the wheels. The wheels are free running so if the plane is going 100 km/hr forward and the treadmill is going 100 km/hr backwards that means the FREE RUNNING WHEELS will be going 200 km/hr and it will take off as normal.

of course that plan would take off, the truck going left was going significantly slower than the plane thus lift occurs

The only way I can see a stationary plane take off is if there was enough airflow created by fans behind or infront of the plane wings

[GerbilFarmer]

the plane would be stationary, nothing would happen



how will it create any forward movement you fuking retard?

Lol the thrust make the forward movement!!! You guys are so dumb

We aren't all gonna make it I guess.

[MillerDecaXC]

LOL @ all the *******s ITT saying that it would actually take off... notsuresrs... are you fukking retards? Misc is full of fukking idiots I swear. Theres no way in hell a treadmill is going to be able to go fast enough to get the speed needed for a plane to lift off the ground. Fukking idiots

[Codo]

So if I sat a hot wheels car (free-spinning wheels) on a flat treadmill and turned the speed to 25 billion MPH, it would just stay stationary?

Correct.

A vehicle with free spinning wheels on a treadmill going 25 billion mph will stay stationary.

A vehicle that uses its wheels to move forward needs to be pushing itself forward 25 billion mph in order to stay stationary on the same treadmill.

[Kev1972]

So if I sat a hot wheels car (free-spinning wheels) on a flat treadmill and turned the speed to 25 billion MPH, it would just stay stationary?

If it was a jet engine powered hot wheels car, yes. Although at that speed friction would probably melt the wheel bearings.

Actually even a propeller powered hotwheels car would work. The speed of its wheels is meaningless. You only need enough thrust to overcome the weight of the plane. Even the wright brothers plane had more thrust than weight.

[Madig]

My friend. MY very good friend. You are misunderstanding something here.

The air around the airplane is stationary. Fine.
The treadmill is moving at 45MPH
the ground is 0mph

Treadmill turns on. BAM. 45mph.
Airplane stays turned off.
Airplane stays 0mph in relation to the ground (0mph) while the treadmill goes 45MPH, because the plane wheels are free spinning.

Airplane engine turns on. the engines GRAB the 0mph air and pulls itself forward until it takes off.

You are correct, but I think that defeats the point of this thought experiment. If it was to grab the air and move forward, then what's the point of the treadmill? All the treadmill is doing is facilitating the equillibrium of forces before any thrust is produced, it is identical to having it sit on a stationary floor. I'm guessing this question was originally asked by someone who didn't have a basic understanding of physics.

[Impudent]

If the treadmill is long enough for the plane to reach takeoff speed then it will take off.

How this question continues to come up is perplexing. Airplanes don't take off using their wheels. The wheels are free spinning via bearings. Hence why airplanes can land and take off on bodies of water even if there is a current. The thrust of the engines propels the plane by acting on the air, not the ground. Assuming we don't get into the fact that the bearings could potentially melt via friction of spinning at very high speeds, a treadmill would be incapable of stopping the plane from traveling down the runway and taking off.

Here's a simplified analogy. If you were on a skateboard on a treadmill and holding a rope tied to the wall you wouldn't move no matter how fast the treadmill was going. Now if you use that rope to pull yourself forward you would move forward. Same concept. The air plane uses the air to move forward. There is no relation to the ground.

so where the fuk is the air underneath the wings moving? NOWHERE

[Breen86]

For bros who cannot understand that wheels do not drive the aircraft i give you...




seaplanes

[wowz]

It cannot take off while on the treadmill unless it is the length of an airstrip

I.e it cannot take off on a treadmill

If it accelerates off the argument is invalid

Ok now we are at the point where different views of the original question presents people with different conclusions and outcomes.

I am not disagreeing with you, but we have different answers because we looked at the question different.

The plane accelerating off the treadmill means to me that the treadmill made no effect and the plan takes off.

[PetPeeve]

Everybody in this topic is arguing different things.

One group is arguing the treadmill will keep the plane in it's exact location, speeding up to perfectly match the plane's increasing speed. Saying this will make it not take off. Correct.

The other group is arguing the plane's velocity will overcome the treadmill's speed, creating forward momentum which will allow it to take off. Also correct.

This topic is stupid.

[afrobrah]

Cannot believe this thread made it to 6 pages, despite it being one of the most overdone threads.

The plane will not take off. You sit it on a treadmill and power up the treadmill and guess what, it will fall off the back as there is nothing powering the wheels forward.

It is not powered by the wheels. It is the airspeed that provides the lift. The faster the plane travels through the air the more lift it can generate. If its sitting in the same spot but just the wheels are moving what difference is it to just a plane sitting still on the runway.


If you sit a plane in a GIANT wind tunnel and crank the wind speed up the plane will be able to lift into the air while not moving forward relative to the ground.
It is the air speed that lifts the plane, not the wheel speed.
And i'm glad turkeychili got banned. Fuk outta here with these repetitive ass threads.

[IcemanIsDead]

Of course if there is no air moving across the wings the plane wouldnt fly, which is what you would imagine would happen if the speed of the plane relative to the treadmill is 0 (unless there is a headwind). But the plane would need to produce very little thrust to overcome the friction of the wheels on the treadmill, thereby increasing the speed relative to the treadmill, almost regardless the speed of the treadmill, so in reality it would be easy for a plane to take off on a treadmill.

The question is based on the fact that the treadmill is able to move as fast as the plane is but in the opposite direction, in which case the plane would not lift. In reality there are no landing strip sized treadmills for a plane to take off from, so reality is more or less invalid.

If you pose that the treadmill is able to counteract the force from the plane it will not lift, since 0 velocity relative to the ground and no air pressure is built u around the wings.

LOL @ all the *******s ITT saying that it would actually take off... notsuresrs... are you fukking retards? Misc is full of fukking idiots I swear. Theres no way in hell a treadmill is going to be able to go fast enough to get the speed needed for a plane to lift off the ground. Fukking idiots

Hahahah 5* trolling brah

[IcemanIsDead]

Everybody in this topic is arguing different things.

One group is arguing the treadmill will keep the plane in it's exact location, speeding up to perfectly match the plane's increasing speed. Saying this will make it not take off. Correct.

The other group is arguing the plane's velocity will overcome the treadmill's speed, creating forward momentum which will allow it to take off. Also correct.

This topic is stupid.

this, if there is enough air pressure around the wings it will lift, if there's not it won't lift.

[Purplekoolaid]

If it doesn't move (via friction or whatever), it would need 32 engines at 15 degrees to take off vertically (aka all lifting force is engine, not air)

If it does move (because thrust is generated from turbofans, not the wheels), then yes

/thread

All depends on how you interpret the question

[DasWunderBrah]

Everybody in this topic is arguing different things.

One group is arguing the treadmill will keep the plane in it's exact location, speeding up to perfectly match the plane's increasing speed. Saying this will make it not take off. Correct.

The other group is arguing the plane's velocity will overcome the treadmill's speed, creating forward momentum which will allow it to take off. Also correct.

This topic is stupid.

this happens every time this thread is created.

[Codo]

Everybody in this topic is arguing different things.

One group is arguing the treadmill will keep the plane in it's exact location, speeding up to perfectly match the plane's increasing speed. Saying this will make it not take off. Correct.

The other group is arguing the plane's velocity will overcome the treadmill's speed, creating forward momentum which will allow it to take off. Also correct.

This topic is stupid.

A car going 45 mph in relation to the ground, on a treadmill going 45mph will go 0mph in relation to the ground.
A plane going 45mph in relation to the ground, on a treadmill going 45mph will go 45mph in relation to the ground.

[wowz]

Everybody in this topic is arguing different things.

One group is arguing the treadmill will keep the plane in it's exact location, speeding up to perfectly match the plane's increasing speed. Saying this will make it not take off. Correct.

The other group is arguing the plane's velocity will overcome the treadmill's speed, creating forward momentum which will allow it to take off. Also correct.

This topic is stupid.

But the force required to overcome a 50mph treadmill is relatively the same if the treadmill is running at 1000mph. The only slight different is bearing friction. So even if the treadmill is trying to keep up with the speed of the plane, the plane will still move forward since the treadmill is irrelevant.


But I do agree that everyone is arguing different scenarios.

[IIIWolverineIII]

Correct.

A vehicle with free spinning wheels on a treadmill going 25 billion mph will stay stationary.

A vehicle that uses its wheels to move forward needs to be pushing itself forward 25 billion mph in order to stay stationary on the same treadmill.

Wrong

Answer: No. The gravity of the little car will hold the wheels to the treadmill, then the combination of that with friction to the treadmill will send it flying backwards unless there was an outside force counteracting the friction/gravity(weight) combo. 

In the airplanes case, the counteracting force would be the engines pushing air behind them. They would have to push enough air to counteract the weight of the plane and the speed of the treadmill. 

If the force produced by the engines is greater than that of the weight/speed combo, then the airplane would move forward and fall off the fukking treadmill. 

In which case, what was the fuking point of a treadmill in the first place? When you fukers run on a treadmill do you go so fast that you run off the front and keep going? Lol

[Breen86]

Ban all fixed landing gear aircraft because the wheels will freewheel in the wind during flight and the planes will fall out of the sky!!!!

[ttaylor0024]

Lawd. I remember now, to take off a plane needs a pressure differential between the top of wing and bottom, which is achieved through velocities. (air traveling faster has greater pressure). The engine's power is transmitted through the wheels still as the plane must use the wheels to roll.

No, in no way, shape, or form is any power sent to the wheels of any aircraft. Thrust is produced from the propeller or jet engine.

yeah, I do and still don't understand how that would disprove that 0 velocity = the plane not lifting.

If the plane has no wind under and over the wings (0 velocity) it can't take off.

If a plane has tailwind it will still not be enough to counteract the jets of a plane, the plane will accelerate faster than the counteracting force of the wind, which will still build enough wind pressure for the plane to lift.

You are correct about if the plane has no relative wind it cannot take off. You are 100% incorrect about every statement you have about wind. Think of it this way, an aircraft wants to be in the air, so all it cares about is air. All forward movement is a result of thrust from the AIR. You can actually take off and land an aircraft flying backwards believe it or not. Just the other day I was taking off out of Lincoln, my wings saw 55kts of relative wind, and my tires only say about 25kts of rotation.

Nooo! The engines push the air through the TURBINES not over the wing! The air being pushed into the turbines is combusted wich produces THRUST, which moves the wings forward which then generates LIFT. In this scenario there is no wings moving forward therefore there is NO LIFT.

(All this is assuming the treadmill keeps the airplane at 0 relative velocity to the ground)

Thrust is relative to the air. If an aircraft is moving backwards 100kts, and needs 100kts of positive airflow over the wings, then it's wheels will be spinning 200kts. The engines dont care at all, and will simply pull their way through the air.

This Mythbusters is flawed in my opinion.

if the thrust is greater than the force the treadmill is generating it will take off because it still has forward movement.

This is because thrust is relative to air! If an aircraft is being moved backwards then it is simply taking off with a tailwind, which we established earlier can be done.

The point is it doesnt matter how fast the tires are spinning. Hell, the treadmill could be spinning in reverse 1000mph.
Your thought process applies to cars, not planes.


If you are on a treadmill with rollerblades and the treadmill is at 1000mph, you could stay in place with only your pinky on the railing. because the wheels are FREE SPINNING.

Not true, while the wheels are free of the engine, the aircraft will still be moving backwards. Try standing on a treadmill on rollerblades without holding on to something, if you don't fall over you will move backwards even though your wheels won't move.

holy **** you guys.

Listen.

FREE SPINNING WHEELS!!!!!!!!!!!!!!!!!!!!!!!!!

That means you can move the treadmill 25 BILLION MPH and the plane won't move an inch. It would sit there safe and sound while the wheels go ape sh*t!

A car does not have free spinning wheels. A car would have to power it's wheels to go 25 Billion MPH to do what hte plane looks like it's doing.

Still wrong, refer to above.



There is literally no way a treadmill can keep an aircraft stationary to the ground.

[Apz123]

Edit yeah im wrong

[ttaylor0024]

Cannot believe this thread made it to 6 pages, despite it being one of the most overdone threads.

The plane will not take off. You sit it on a treadmill and power up the treadmill and guess what, it will fall off the back as there is nothing powering the wheels forward.

It is not powered by the wheels. It is the airspeed that provides the lift. The faster the plane travels through the air the more lift it can generate. If its sitting in the same spot but just the wheels are moving what difference is it to just a plane sitting still on the runway.


If you sit a plane in a GIANT wind tunnel and crank the wind speed up the plane will be able to lift into the air while not moving forward relative to the ground.
It is the air speed that lifts the plane, not the wheel speed.
And i'm glad turkeychili got banned. Fuk outta here with these repetitive ass threads.

You are completely wrong. The engines / propeller move AIR. Now we move back to the "can we take off with a tailwind" question.




If you're not a pilot, or aerospace engineer, you probably have no clue what you're talking about.

[Xeledon]

M. Sc. physics checking in. highly entertaining thread. 5 stars

The answer is easy, the plane will take off. The reason for that has been stated at least 20 times in the thread already: free spinning wheels. The treadmill has no effect on the plane, whether it is turned off or on, it doesn´t matter (only the rpm of the wheels will change, which still has no effect on the plane). lulz were had.

repped op