Can this airplane take off?

[nist7]

okay, so I read this on another forum and it generated some good debate.

There is an airplane on a run way. The run way is like a conveyor belt, and can detect the speed of the wheels of the airplane. When the run way senses the wheels moving, the run way will move match the speed of the airplane's wheels but in the opposite direction.

Can this airplane take off?

Discuss.

[Night_Hawk]

I know the answer but I will hold it for now since nobody else posted yet

nobody wants a first post ending lol

[CrazyRussian540]

I too know the answer, but I don't think a second post ending would be too nice either...

[nist7]

awww, dammit. I'm still undecided....lol

[mgkdk]

It's also been posted before, but I'm too lazy to go look for it

[Alok]

The airplane will be able to take off, mainly because the wheels aren't what drives the plane forwards.

Generally, if the wheels were to power the plane, the conveyor belt moving the opposite way would cause lack of thrust, because the wheels use the belt as the surface to exert force that results in motion.

In the case of this plane, which is powered by jet or turbine engines, it uses the air as the medium against which a force is exerted, which is at the same place irrelevant of the conveyor belt moving or not, so the plane will move, allowing it to take off....

....or so I think.

[Final Daihatsu]

Right, I'll Explain why who thought of this idea FAILS.

Imagine yourself a Caparo T1 on that conveyor. Now imagine that conveyor is able to change its shape and transform into a corner. If you accelerate the Caparo up to 200mph and the conveyor becomes a corner, you have to turn. But "Oh no!", the Caparo doesn't have any downforce, hence it will understeer and you will wreck a 200k quid hypercar.

Why it doesn't have downforce? because there isn't wind. Why there isn't any wind? Because that T1 stays exactly at the same point all that time. Air doesn't pass through all the spoilers and everything, and no downforce is produced.

Same goes for the plane. No wind, no UPFORCE this time, and the plane wouldn't take off.

(Go ahead, flame me for explaning )

[Night_Hawk]

Originally Posted by Final Daihatsu

Right, I'll Explain why who thought of this idea FAILS.

Imagine yourself a Caparo T1 on that conveyor. Now imagine that conveyor is able to change its shape and transform into a corner. If you accelerate the Caparo up to 200mph and the conveyor becomes a corner, you have to turn. But "Oh no!", the Caparo doesn't have any downforce, hence it will understeer and you will wreck a 200k quid hypercar.

Why it doesn't have downforce? because there isn't wind. Why there isn't any wind? Because that T1 stays exactly at the same point all that time. Air doesn't pass through all the spoilers and everything, and no downforce is produced.

Same goes for the plane. No wind, no UPFORCE this time, and the plane wouldn't take off.

(Go ahead, flame me for explaning )

the plane would take off, I sort of follow what you're saying about the T1 but you gotta realize that the caparo is driven by wheels, the conveyor belt under the plane could be going mach 2 (assuming the wheel bearings are absolutley badass on this particular plane) but as long as some air floats through the engines, it will start to advance forward until eventually lifting off, sure the wheels might be spinning a rediculous speed but it just doesnt matter in this case

just the difference between torque and thrust

[the Interceptor]

OMG here we go again!

You guys know this question can pretty much screw up a whole forum, right? So make sure you really wanna do this.

Anyway, Alok has pretty much said it already. A plane is propelled by its engines. As the wheels are there only to prevent the fuselage rubbing over the ground, they play no role in the actual movement. Therefore, whatever the conveyor belt does, the plane will accelerate, reach take-off speed and leave ground.

[KaJuN]

Just use a Harrier and take all the guesswork out of it!

[D-Fence]

It can take of, as long as the wheels can take the incredible spin.

Why?

The Jet engine moves the plane, not the wheels. It needs a stream of air with a certain speed on the wings to take off (in fact, different streams, benoulli effect). The wheels would just start to go insanely fast, because the conveyor belt would move really fast, when the plane starts moving, in reality, the wheels would possibly blow up......they do at least twice the airplane speed...

Just imagine a toy car on a piece of paper on the desk. If you push it from behind and keep pulling the paper away, it still moves

The only way to make it stay grounded is a fan behind the plane that keeps blowing air with the same speed the plane is moving from behind on the wings......

[Final Daihatsu]

So Basically, as the plane starts to push itself, the conveyor just needs to slow down. (Quote: "The run way is like a conveyor belt, and can detect the speed of the wheels of the airplane.")

In fact, that means this conveyor is pretty useless! Apart from if it had a massive fan in the far end

[MXM]

Didn't whole internet go over this like 3 years ago?

[the Interceptor]

Originally Posted by Final Daihatsu

So Basically, as the plane starts to push itself, the conveyor just needs to slow down.

huh?!

[gtrietsc]

Just when you think people can't get any dumber....

A plane flies by air moving over its wings. You can have the wheels spinning as fast as you want on a treadmill, but no air is moving over the wings. Therefore it will never take off. The treadmill actually counters any air movement.

Think about it. If it would work, why havent we retrofitted all our aircraft carriers with this incredible idea?

I have seen tuna sandwiches smarter than some people in this, the worst of all internet debates of 2007.

[No Boss]

Originally Posted by MXM

Didn't whole internet go over this like 3 years ago?

Yes... and look where it got us.

/I'll take my plane on proper tarmac, not you're redneck treadmill.
//Planes don't need exercise.
///No one can make a treadmill that big.
//make believe apparently still trumps logic and reason.
/...../

[Ford Prefect]

you people are such anoraks...

Originally Posted by D-Fence

It can take of, as long as the wheels can take the incredible spin.

probably the only post that relates to reality, where the wheel bearings would eventually melt, as the conveyor would go up to the speed of light, causing the plane not to take off, on the other hand (and again, in reality), no real conveyor would be able to run that fast... but in ACTUAL reality no one would be stupid enough to conduct such an experiment, so the question itself is quite stupid...

Originally Posted by Final Daihatsu

Right, I'll Explain why who thought of this idea FAILS.

Imagine yourself a Caparo T1 on that conveyor. Now imagine that conveyor is able to change its shape and transform into a corner. If you accelerate the Caparo up to 200mph and the conveyor becomes a corner, you have to turn. But "Oh no!", the Caparo doesn't have any downforce, hence it will understeer and you will wreck a 200k quid hypercar.

Why it doesn't have downforce? because there isn't wind. Why there isn't any wind? Because that T1 stays exactly at the same point all that time. Air doesn't pass through all the spoilers and everything, and no downforce is produced.

the truth is, the car would explode before you could magically turn your conveyor into a corner because there wouldn´t be any air cooling the engine...

[Final Daihatsu]

Originally Posted by gtrietsc

Just when you think people can't get any dumber....

A plane flies by air moving over its wings. You can have the wheels spinning as fast as you want on a treadmill, but no air is moving over the wings. Therefore it will never take off. The treadmill actually counters any air movement.

Think about it. If it would work, why havent we retrofitted all our aircraft carriers with this incredible idea?

I have seen tuna sandwiches smarter than some people in this, the worst of all internet debates of 2007.

That is exactly what I said. No wind, no upforce, no takeoff.

Originally Posted by the Interceptor

huh?!

Think about it, as the plane accelerate in its way to hell the wheels spin even faster than the plane itself! so to keep them from exploding the conveyor will have to slow down.

[Shadowness]

How the hell can people think it can take off!

If the conveyor moves in a equal opposite direction, how does the plance actually move?! Its like running on a treadmill, you dont move anywhere!

[the Interceptor]

Originally Posted by gtrietsc

Just when you think people can't get any dumber....

I have seen tuna sandwiches smarter than some people in this, the worst of all internet debates of 2007.

*voice from the off*

Congratulations! You've just initiated phase two of the destruction of this forum. Please await being flamed to initiate phase three.

Originally Posted by gtrietsc

A plane flies by air moving over its wings.

Correct!

Originally Posted by gtrietsc

You can have the wheels spinning as fast as you want on a treadmill, but no air is moving over the wings.

Stop! What you're assuming is that the plane is standing still because it rolls on a treadmill. As stated before the wheels have no job in propelling a plane, which means that in whatever direction and at whichever speed they may be rolling, they won't stop the engines from pushing the plane through the surrounding air.

Originally Posted by gtrietsc

Think about it. If it would work, why havent we retrofitted all our aircraft carriers with this incredible idea?

Because the treadmill doesn't shorten the actual distance the plane needs to cover to be able to take off.

Originally Posted by Shadowness

If the conveyor moves in a equal opposite direction, how does the plance actually move?! Its like running on a treadmill, you dont move anywhere!

That's true, but you are propelled by your legs. A plane isn't propelled by its wheels though.

EDIT: you might also wanna read this thread: http://forums.finalgear.com/showthre...light=conveyor