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Froggystyle
11-05-2006, 01:12 PM
Is stupid. It flies. As it has been explained a million times, it flies. The wheels go double the speed, and it rotates and takes off.
That being said...
In a purely theoretical world, I have figured out a way that it would be prevented from flying, but it disagrees with everyone who is claiming it won't fly, so you are still wrong on all levels. Assume the following...
The wheel bearings do generate some resistance when rolling forward. If the conveyor belt truly could increase speed not only exponentially but to an absurd top speed, it could continue counteracting the rotating resistance inherent in the wheel bearings until the airplane's thrust could not overcome the resistance in the wheel bearings. Also assumed but not possible in any case is that the wheels and tires would stay together long enough for this to happen.
As it has been described, a plane on a dry runway doesn't overcome it's brakes. The brakes WILL hold the plane in place at full throttle, which leads me to believe that skidding tires against the resistance is not likely. Assume that the brakes on would be full resistance possible, the plane won't roll.
It is a stretch, but depending on the theoretical limits of the argument, this is the only way where the answer could be wrong.
By my rough calculations, the treadmill would have to increase it's speed nearly exponentially through something in the neighborhood of 1000mph, a speed roughly four times what the tires would take before becoming history.
So if the following impossible situations were possible...
1) the conveyor belt could accelerate from 0-600 mph in a couple of seconds
2) the wheel bearings could stay together long enough to provide enough resistance to counter the thrust of the motor
3) the tires could stay together for the same period
4) the pilot would be good enough to keep the plane going straight through all of this (you need to assume that all of the wheel assemblies won't offer the same exact resistance, and on an exponential curve, that will make big heading changes
Then the plane wouldn't be able to leave the ground.
Any takers?

LUVNLIFE
11-05-2006, 01:17 PM
That just doesn't fly with me :rollside: :rollside:

JustMVG
11-05-2006, 01:20 PM
As God is my witness.... a couple of pilots were going over the same friggin thing , one of the guys went over and got a rubber band powered plane started up a treadmill that was there and then now hee is the the fun part WOUND UP THE RUBBER BAND POWERED PROPELLOR then placed the plane on the already moving treadmill, and can you believe it darn toy airplane flew.... all thae damn thing proves is that if you get enough bored pilots around something like this is bound to happen.
I have seen this thing 50 times and 400 different theories on this subject.... it's so 2005 lets let it go and die and become a thread someone who's had a few pulls it up out of the archives ......

Jordy
11-05-2006, 01:23 PM
I agree that a plane will take off from a treadmill and the wheels will just be going twice as fast if the treadmill is matching the airspeed of the plane. But none of that is stated in the question.
It says nothing of airspeed, ground speed, wheel speed, only that that belt will exactly counter the speed of the plane. If it's exactly countering it, the plane isn't moving, therefore, no lift is created and the plane won't fly. ;)

Jbb
11-05-2006, 01:24 PM
I was quite surprised about the brakes holding at full throttle....I was sure the first time on the run up pad with an A300 or L1011 they would skid a bit......they buck violently... :p ...and bounce around quite a bit...so much so that it is hard to focus on anything.....but they didnt move...

ratso
11-05-2006, 01:25 PM
I'm still not satisfied... I don't think it will take off.

Froggystyle
11-05-2006, 01:32 PM
I agree that a plane will take off from a treadmill and the wheels will just be going twice as fast if the treadmill is matching the airspeed of the plane. But none of that is stated in the question.
It says nothing of airspeed, ground speed, wheel speed, only that that belt will exactly counter the speed of the plane. If it's exactly countering it, the plane isn't moving, therefore, no lift is created and the plane won't fly. ;)
Jane, you ignorant slut.
I am not getting into this. I already stated the only possible method of keeping the plane from flying. And it isn't possible.
It flies. Period. Everyone has done a great job explaining it, and if you don't figure it out soon, I am going to go side with Miguel. ;)

BajaMike
11-05-2006, 01:34 PM
I was quite surprised about the brakes holding at full throttle....I was sure the first time on the run up pad with an A300 or L1011 they would skid a bit......they buck violently... :p ...and bounce around quite a bit...so much so that it is hard to focus on anything.....but they didnt move...
Take off in a 757 from John Wayne airport....they do it every time....stand on the brakes, power up to full throttle, release the brakes, accelerate like crazy, then rotate and enjoy the steepest climb out you ever will in a commercial jet....It reaches 500 feet before in crosses the end of the runway.
It's fun, a real e-ticket ride..... :idea:
:rollside:

Jordy
11-05-2006, 01:35 PM
And it isn't possible.
OK, so let's get into the mechanical ramifications of building a treadmill, runway length that will instantaneously accelerate to the exact opposite speed of a plane, be it a Piper, a Lear, or a 747. Doesn't seem all that possible either. ;) :D

jimslade
11-05-2006, 01:36 PM
As God is my witness.... a couple of pilots were going over the same friggin thing , one of the guys went over and got a rubber band powered plane started up a treadmill that was there and then now hee is the the fun part WOUND UP THE RUBBER BAND POWERED PROPELLOR then placed the plane on the already moving treadmill, and can you believe it darn toy airplane flew.... all thae damn thing proves is that if you get enough bored pilots around something like this is bound to happen.
I have seen this thing 50 times and 400 different theories on this subject.... it's so 2005 lets let it go and die and become a thread someone who's had a few pulls it up out of the archives ......
The prop on the toy airplane is generating the air speed over the wings to generate lift. On a jet airplane the thrust would Never generate enought airflow to allow lift.

topless
11-05-2006, 01:39 PM
So what happens if 2 bitches and an ignorant slut are on the same treadmill?

Jbb
11-05-2006, 01:40 PM
Take off in a 757 from John Wayne airport....they do it every time....stand on the brakes, power up to full throttle, release the brakes, accelerate like crazy, then rotate and enjoy the steepest climb out you ever will in a commercial jet....It reaches 500 feet before in crosses the end of the runway.
It's fun, a real e-ticket ride..... :idea:
:rollside:
I have been on many test flights in the 757. The first ones delivered were to the company I worked for....incredible climb rate....but nothing has ever set me back in my seat on a t/o run like an empty L1011...with an anxious flight crew... :p

Froggystyle
11-05-2006, 01:41 PM
So what happens if 2 bitches and an ignorant slut are on the same treadmill?
They race outboard powered boats.

Froggystyle
11-05-2006, 01:42 PM
I am so seriously let down by anyone saying it actually won't fly and are serious about it.
If you are claiming it won't fly, but are ****ing with everyone... please PM me so I don't continue thinking less of you. If you aren't screwing with everyone... here's your sign.

ratso
11-05-2006, 01:42 PM
So what happens if 2 bitches and an ignorant slut are on the same treadmill?
I'm in on that if I can have the ignorant slut...

mickeyfinn
11-05-2006, 01:49 PM
I agree with everything said, but the question says the conveyor will match the SPEED of the airplane. Speed is a measurement of rate of movement. In order for your failure scenario to happen you would have to be basing the speed of the conveyor on the "calculated" speed based on wheel rpm. I don't ever remember seeing that type of speedometer on an airplane. So as long as everything could handle 2x the speed required for take off, everything would be normal. I doubt the additional wheel rpms would even be measurable in the cockpit from a power standpoint. If calculated wheel speed were used, the bearings and conveyor would have to be capable of running to infinity (up to the point of bearing or tire failure) since the wheels would always be ahead of the conveyor in speed.

Froggystyle
11-05-2006, 01:51 PM
I agree with everything said, but the question says the conveyor will match the SPEED of the airplane. Speed is a measurement of rate of movement. In order for your failure scenario to happen you would have to be basing the speed of the conveyor on the "calculated" speed based on wheel rpm. I don't ever remember seeing that type of speedometer on an airplane. So as long as everything could handle 2x the speed required for take off, everything would be normal. I doubt the additional wheel rpms would even be measurable in the cockpit from a power standpoint. If calculated wheel speed were used, the bearings and conveyor would have to be capable of running to infinity (up to the point of bearing or tire failure) since the wheels would always be ahead of the conveyor in speed.
Right. It flies is the bottom line.
I would like to locate whichever cretin first posed this question and poke them in the eye.

ratso
11-05-2006, 01:52 PM
If the speed of the conveyor matched the speed of the plane that it theoretically was moving, it ain't FUKKIN' HAPPENING... unless it's a FUKKIN' HARRIER or something like that. The plane will not take off because it's speed moving forward is ZERO!!!!!!!!!!!!

Froggystyle
11-05-2006, 01:53 PM
If the speed of the conveyor matched the speed of the plane that it theoretically was moving, it ain't FUKKIN' HAPPENING... unless it's a FUKKIN' HARRIER or something like that. The plane will not take off because it's speed moving forward is ZERO!!!!!!!!!!!!
See post #14 and apply.

BajaMike
11-05-2006, 01:54 PM
....but nothing has ever set me back in my seat on a t/o run like an empty L1011...with an anxious flight crew... :p
Sounds like fun.....I was the only passenger on a old LearJet24, taking off out of Chico....I asked the pilots "how steep can this climb?" They said "buckle up, we'll show you". Wow, seemed like it was going straight up, like a rocket, and 20,000 feet in about 2.5 minutes.....
:idea:

ratso
11-05-2006, 01:55 PM
Wait, I think I got it now... It will fly!!!!!!!!!!!!!!!

Froggystyle
11-05-2006, 01:57 PM
Wait, I think I got it now... It will fly!!!!!!!!!!!!!!!
Correct. I will take that sign back from you and give it to someone else.
I am relieved to have gotten a couple of PM's on this one... it appears most are having fun at the expense of others...

BajaMike
11-05-2006, 01:58 PM
The plane flies......
Take the airplane, and strap both the wings to the runnway next to the treadmill....get the treadmill going 200 or 300 miles per hour, hell get it going 1000 miles per hour, power up the jet engines to full throttle, release the wing straps, and the planes shoots down the runnway and takes off. :idea:
The plane doesn't care at what speed the wheels are turning, it's going to fly. :cool:
:argue:

ratso
11-05-2006, 01:59 PM
The plane flies......
Take the airplane, and strap both the wings to the runnway next to the treadmill....get the treadmill going 200 or 300 miles per hour, hell get it going 1000 miles per hour, power up the jet engives to full throttle, release the wing straps, and the planes shoots down the runnway and takes off. :idea:
The plane doesn't care at what speed the wheels are turning, it's going to fly. :cool:
:argue:
Best explanation yet...

Schiada76
11-05-2006, 04:57 PM
For facks sake you gawdamned imbeclies, the plane is "pushing" against the air the fawiking treadmill doesn't have any fcking thjing to do with it!! :220v:
Note: Not really pissed but I'm pissed in the British sense. :shift:

Schiada76
11-05-2006, 05:00 PM
Aww CHIT!!!!
I'm ****ing brilliant when I've been drinking vodka!!
I'm opening up a new airport with a 100 yard runway. Of course the runway is a treadmill and we'll just reverse it for landings.
So if a plane is landing at 300mph and the treadmill is moving at the EXACT same speed will the plane land standing still? :crossx: :220v:

beaverretriever
11-05-2006, 05:44 PM
LOL, I didnt think my stupid thread would spawn so many other threads. :p
This is the conclusion I came too.
McRib>Treadmill :)

LUVNLIFE
11-05-2006, 05:47 PM
This one was almost as good as the thread in Just Jets a few years ago. They argued whether a jet boat was all thrust or if it pushed off the water behind the boat. :rolleyes: :p :rollside:

ratso
11-05-2006, 05:48 PM
This one was almost as good as the thread in Just Jets a few years ago. They argued whether a jet boat was all thrust or if it pushed off the water behind the boat. :rolleyes: :p :rollside:
...how did that one end up?

LUVNLIFE
11-05-2006, 05:55 PM
The treadmill locked up and it flew :p :rollside:

Prop Rod
11-05-2006, 06:37 PM
Dont know if someone has said this or not, but dont you think this would be a great subject for myth-busters?

boatsnblondes
11-05-2006, 07:44 PM
So what happens if 2 bitches and an ignorant slut are on the same treadmill?
Who cares? As long as I can video tap it.............

Cas
11-05-2006, 08:19 PM
so, I suppose once the plane is flying off the treadmill you would be able to hit the brakes and it would fall to the ground?

Jordy
11-05-2006, 08:33 PM
They argued whether a jet boat was all thrust or if it pushed off the water behind the boat. :rolleyes: :p :rollside:
Wouldn't that be the same thing??? I'm going to go out on a limb and suggest it was the conversation about if a jetboat pulled it's way through the water, via impeller, or pushed it's way through via nozzle. Figure either way, it just proves that jetboats suck. :D :D :D

Infomaniac
11-05-2006, 08:40 PM
It took me reading it many times before I figured out wheels twice as fast and it flies. i never owned up to it. LOL
But not the way I read it in the beginning.

ROZ
11-05-2006, 10:15 PM
incredible climb rate....but nothing has ever set me back in my seat on a t/o run like an empty L1011...with an anxious flight crew... :p
You should try stirrup play with Topless :D

Tom Brown
11-05-2006, 10:25 PM
You should try stirrup play with Topless :D
Giddyup! :) :) :)

LUVNLIFE
11-06-2006, 04:10 AM
Wouldn't that be the same thing??? I'm going to go out on a limb and suggest it was the conversation about if a jetboat pulled it's way through the water, via impeller, or pushed it's way through via nozzle. Figure either way, it just proves that jetboats suck. :D :D :D
Yea that's it :p :rollside: