Will the Plane Take-Off - Merged with MythBusters Show Thread
10-22-2007, 03:13 PM
#482
Originally Posted by Whiskers
Ok, I see now and I agree on the following:
-The jets will cause the plane to move as fast as it would with or without the treadmill.
-If the treadmill was very long, it will take off of the treadmill.
-The jets will cause the plane to move as fast as it would with or without the treadmill.
-If the treadmill was very long, it will take off of the treadmill.
10-22-2007, 03:14 PM
#483
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Maybe think of it this way: A Jet Car is running down a conveyor belt. Does it just sit there if the converor has any speed to it? The jet propulsion does not have to overcome the speed of the conveyor, just the wind resistence.
10-22-2007, 03:15 PM
#484
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Originally Posted by Whiskers
Ok, I see now and I agree on the following:
-The jets will cause the plane to move as fast as it would with or without the treadmill.
-If the treadmill was very long, it will take off of the treadmill.
-The jets will cause the plane to move as fast as it would with or without the treadmill.
-If the treadmill was very long, it will take off of the treadmill.
Yeah I would argue that the treadmill would have to be as long if not longer than a regular runway, the plane still has to get up to speed the physics of the plane getting into the air hasn't changed...
because the treadmill is fixed to the ground, and the plane is moving through space (air) using space (air) it's not really a fair contest between the two.
10-22-2007, 03:15 PM
#485
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Originally Posted by JJ4Short
No do not back out on this you bastard. Can you overtake a treadmill that is going as fast as you? NO so the plane can't either and if it does start to lift for whatever reason it will hit the ground.
You use your legs to move forward. A plane uses a jet engine.
they are TOTALLY different.
explain to me how those are acceptable comparisons?
10-22-2007, 03:16 PM
#486
Insert Sarcasm Here
Originally Posted by JJ4Short
From what I read in the original post the treadmill will constantly match the planes speed so its not moving!
I don't know why I am getting so bent up but its crazy to me!
I don't know why I am getting so bent up but its crazy to me!
10-22-2007, 03:18 PM
#487
Go Giants
Originally Posted by JJ4Short
No do not back out on this you bastard. Can you overtake a treadmill that is going as fast as you? NO so the plane can't either and if it does start to lift for whatever reason it will hit the ground.
10-22-2007, 03:18 PM
#488
Originally Posted by levon1830
Think about this question: can a powerful jetski--let's assume the 2007 Sea-Doo RXT with its 215 hp supercharged engine--travel upstream in a fast-moving river?
If the stream is just as fast as the jetski No, its impossible.
I believe the plane might start lifting up because of natural air blowing by eventually but it will fall on its belly.
Why do you guys keep saying "The plane is not going the speed of the wheels" Yes it is, if the wheels aren't going anywhere the plane is standing still. if you kick it the jets unless they are some powerful jets the planes not going anywhere.
If the plane could leave the treadmill we would only need runways for landing. The plane is not moving...the end therefore its up to the thrust of the jets, now if the thrust of the jets can make it take off without use of the runway then you have a fucking fast jet.
10-22-2007, 03:19 PM
#489
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Why take up so much space at airports with half mile runways if a plane could launch stationary on a big treadmill?
Its because it's not possible. As the engines try to propel the plane foward, the treadmill is pulling it back, so think of it this way.......if the plane's engines were shut off, the plane would move backwards being pulled by the treadmill......turn them on and the engines are only countering the effects of the treadmill to keep it in place. As long as the treadmill is going to match the speed of the plane in the opposite way, the plane will not take off.
Its because it's not possible. As the engines try to propel the plane foward, the treadmill is pulling it back, so think of it this way.......if the plane's engines were shut off, the plane would move backwards being pulled by the treadmill......turn them on and the engines are only countering the effects of the treadmill to keep it in place. As long as the treadmill is going to match the speed of the plane in the opposite way, the plane will not take off.
10-22-2007, 03:20 PM
#490
Three Wheelin'
Originally Posted by Smalls
Thats right. But since the plane doesn't depend on the wheels for foward motion, it doesn't matter.
10-22-2007, 03:20 PM
#491
Go Giants
Originally Posted by cibs
Yeah I would argue that the treadmill would have to be as long if not longer than a regular runway, the plane still has to get up to speed the physics of the plane getting into the air hasn't changed...
because the treadmill is fixed to the ground, and the plane is moving through space (air) using space (air) it's not really a fair contest between the two.
because the treadmill is fixed to the ground, and the plane is moving through space (air) using space (air) it's not really a fair contest between the two.
10-22-2007, 03:21 PM
#492
Three Wheelin'
Originally Posted by JJ4Short
If the stream is just as fast as the jetski No, its impossible.
I believe the plane might start lifting up because of natural air blowing by eventually but it will fall on its belly.
Why do you guys keep saying "The plane is not going the speed of the wheels" Yes it is, if the wheels aren't going anywhere the plane is standing still. if you kick it the jets unless they are some powerful jets the planes not going anywhere.
If the plane could leave the treadmill we would only need runways for landing. The plane is not moving...the end therefore its up to the thrust of the jets, now if the thrust of the jets can make it take off without use of the runway then you have a fucking fast jet.
I believe the plane might start lifting up because of natural air blowing by eventually but it will fall on its belly.
Why do you guys keep saying "The plane is not going the speed of the wheels" Yes it is, if the wheels aren't going anywhere the plane is standing still. if you kick it the jets unless they are some powerful jets the planes not going anywhere.
If the plane could leave the treadmill we would only need runways for landing. The plane is not moving...the end therefore its up to the thrust of the jets, now if the thrust of the jets can make it take off without use of the runway then you have a fucking fast jet.
10-22-2007, 03:22 PM
#493
Originally Posted by cibs
You use your legs to move forward. A plane uses a jet engine.
they are TOTALLY different.
explain to me how those are acceptable comparisons?
they are TOTALLY different.
explain to me how those are acceptable comparisons?
The plain is not moving through "space" until it has enough lift to lift itself off the ground. What does it need to do this? LIFT, what makes lift? Wind going under the wings. How do you make wind go under the wings...move it down the runway. What happens if it is not moving down the runway? No Lift...therefore it is not in the air...there for it might lift a little from the jets but fall right on its belly.
UNLESS said Jets are strong enough to have the plane take off from standstill.
10-22-2007, 03:22 PM
#494
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Originally Posted by JJ4Short
If the stream is just as fast as the jetski No, its impossible.
I believe the plane might start lifting up because of natural air blowing by eventually but it will fall on its belly.
Why do you guys keep saying "The plane is not going the speed of the wheels" Yes it is, if the wheels aren't going anywhere the plane is standing still. if you kick it the jets unless they are some powerful jets the planes not going anywhere.
If the plane could leave the treadmill we would only need runways for landing. The plane is not moving...the end therefore its up to the thrust of the jets, now if the thrust of the jets can make it take off without use of the runway then you have a fucking fast jet.
I believe the plane might start lifting up because of natural air blowing by eventually but it will fall on its belly.
Why do you guys keep saying "The plane is not going the speed of the wheels" Yes it is, if the wheels aren't going anywhere the plane is standing still. if you kick it the jets unless they are some powerful jets the planes not going anywhere.
If the plane could leave the treadmill we would only need runways for landing. The plane is not moving...the end therefore its up to the thrust of the jets, now if the thrust of the jets can make it take off without use of the runway then you have a fucking fast jet.
You still never addressed the holding a rope while on rollerblades on a treadmill scenario.
the plane does not go the speed of the wheels if it's on a treadmill. speed is relative to space right? to other landmarks on the ground.
Let's try this - you're wearing rollerblades on a treadmill holding onto a rope fastened to the wall infront of you. the treadmill is set to it's highest speed...
So the wheels on the rollerblades are moving at say 10mph... according to your argument because the wheels are moving at 10mph you are too?
10-22-2007, 03:24 PM
#495
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Originally Posted by JJ4Short
The plain is not moving through "space" until it has enough lift to lift itself off the ground. What does it need to do this? LIFT, what makes lift? Wind going under the wings. How do you make wind go under the wings...move it down the runway. What happens if it is not moving down the runway? No Lift...therefore it is not in the air...there for it might lift a little from the jets but fall right on its belly.
UNLESS said Jets are strong enough to have the plane take off from standstill.
UNLESS said Jets are strong enough to have the plane take off from standstill.
EVERYTHING moves through space when moving. when it lifts off the ground it's still moving through space except now instead of moving in a linear fashion bound by gravity it's moving up away from gravity as well as forwards.
and the air from the jets would not lift the jet up at all if the scenario you pose would be true... would never happen
10-22-2007, 03:24 PM
#496
Originally Posted by levon1830
The plane does not achieve forward motion via force applied to the ground through its wheels. The wheels are on a plane to make it easier to achieve forward motion with a less powerful engine.
10-22-2007, 03:24 PM
#497
Three Wheelin'
Originally Posted by JJ4Short
The plain is not moving through "space" until it has enough lift to lift itself off the ground. What does it need to do this? LIFT, what makes lift? Wind going under the wings. How do you make wind go under the wings...move it down the runway. What happens if it is not moving down the runway? No Lift...therefore it is not in the air...there for it might lift a little from the jets but fall right on its belly.
UNLESS said Jets are strong enough to have the plane take off from standstill.
UNLESS said Jets are strong enough to have the plane take off from standstill.
10-22-2007, 03:24 PM
#498
Senior Moderator
Originally Posted by JJ4Short
No do not back out on this you bastard. Can you overtake a treadmill that is going as fast as you? NO so the plane can't either and if it does start to lift for whatever reason it will hit the ground.
You move on the treadmill by pushing off against the ground. Your forward speed is directly related and effected by the movement of the ground. So if the ground is moving backwards you have to push twice as hard. The difference here is that a plane pushes against the air to move forward, and the treadmill moving underneath wont change that.
If the AIR was moving backwards (lets say a very strong wind) then that might prevent it from moving forward.
10-22-2007, 03:24 PM
#500
Go Giants
Originally Posted by JJ4Short
The plain is not moving through "space" until it has enough lift to lift itself off the ground. What does it need to do this? LIFT, what makes lift? Wind going under the wings. How do you make wind go under the wings...move it down the runway. What happens if it is not moving down the runway? No Lift...therefore it is not in the air...there for it might lift a little from the jets but fall right on its belly.
UNLESS said Jets are strong enough to have the plane take off from standstill.
UNLESS said Jets are strong enough to have the plane take off from standstill.
10-22-2007, 03:26 PM
#502
Bent = #1
Originally Posted by salvo24
Why take up so much space at airports with half mile runways if a plane could launch stationary on a big treadmill?
The planes have to land somewhere..
10-22-2007, 03:26 PM
#503
Go Giants
Originally Posted by dom
Winter ban games. JJ and whiskers get my nomination.
10-22-2007, 03:27 PM
#504
Senior Moderator
http://txfx.net/2005/12/08/airplane-on-a-conveyor-belt/
When an airplane takes off, there is one major forward force… the forward thrust. The main rearward force is air resistance. The turning of the wheels provides a small frictional force, but because the wheels are free-rolling, this friction is very small. Unless the wheels are locked, the friction is always going to be less than the thrust, which means that the overall force is still forward, and the plane will still move.
Gah… people are freakin’ stupid.
When an airplane takes off, there is one major forward force… the forward thrust. The main rearward force is air resistance. The turning of the wheels provides a small frictional force, but because the wheels are free-rolling, this friction is very small. Unless the wheels are locked, the friction is always going to be less than the thrust, which means that the overall force is still forward, and the plane will still move.
Gah… people are freakin’ stupid.
10-22-2007, 03:28 PM
#506
Insert Sarcasm Here
Originally Posted by levon1830
The plane does not achieve forward motion via force applied to the ground through its wheels. The wheels are on a plane to make it easier to achieve forward motion with a less powerful engine.
oh i agree. the plane does not stay stationary.
10-22-2007, 03:30 PM
#509
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Originally Posted by dom
http://txfx.net/2005/12/08/airplane-on-a-conveyor-belt/
When an airplane takes off, there is one major forward force… the forward thrust. The main rearward force is air resistance. The turning of the wheels provides a small frictional force, but because the wheels are free-rolling, this friction is very small. Unless the wheels are locked, the friction is always going to be less than the thrust, which means that the overall force is still forward, and the plane will still move.
Gah… people are freakin’ stupid.
When an airplane takes off, there is one major forward force… the forward thrust. The main rearward force is air resistance. The turning of the wheels provides a small frictional force, but because the wheels are free-rolling, this friction is very small. Unless the wheels are locked, the friction is always going to be less than the thrust, which means that the overall force is still forward, and the plane will still move.
Gah… people are freakin’ stupid.
Nice link, has the most complete explanation I've read so far, with examples and everything. If after reading that you don't get it then I'll take your money JJ. Given that mythbusters tests it properly.
10-22-2007, 03:30 PM
#510
Go Giants
Originally Posted by JJ4Short
BTW what kind of plane are we talking about?
Big difference between an A810 and an F16
Big difference between an A810 and an F16
10-22-2007, 03:30 PM
#511
Hmm I am starting to rethink this...how powerful are jet engines at full thrust...someone get back to me on this...NO bets fuck you guys No bans either DOM rich Canadian bastard and by bastard I mean super great guy.
10-22-2007, 03:31 PM
#512
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aggggh this is killing me. If the plane can overcome the threadmill (assuming it's infinite is size) than it breaks the assumption that the threadmill can match the planes speed.
10-22-2007, 03:31 PM
#513
Three Wheelin'
Originally Posted by Smalls
oh i agree. the plane does not stay stationary.
Yeah, I know. I was just trying to clear things up for those who still think the plane achieves forward motion via energy applied to the earth (or runway, or conveyor belt) via its wheels.
10-22-2007, 03:32 PM
#514
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Originally Posted by JJ4Short
Hmm I am starting to rethink this...how powerful are jet engines at full thrust...someone get back to me on this...NO bets fuck you guys No bans either DOM rich Canadian bastard and by bastard I mean super great guy.
It would depend on the engine. But you'd have to assume that the engine on any given plane is enough to make it fly. If that isn't the case it wouldn't be a plane it would be a hunk of metal with some engines that push it around.
This scenario calls for a plane.
10-22-2007, 03:33 PM
#516
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Originally Posted by AQUI NO!
aggggh this is killing me. If the plane can overcome the threadmill (assuming it's infinite is size) than it breaks the assumption that the threadmill can match the planes speed.
the treadmill can go 5 times faster than the plane if it wants... the plane will still take off....
10-22-2007, 03:40 PM
#518
10-22-2007, 03:40 PM
#519
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Originally Posted by Whiskers
No...I swiched sides last page...
Good job converting. I used to think it wouldn't take off either. Notice how people switch from "not taking off" to "taking off" but not vice versa. . .
