Brain Teaser - Will it take off??
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Joined: Jul 2005
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From: off the path in Louisiana
LOL just saw this on mythbusters.... go figure
An airplane cannot take off from a runway which is moving backwards (like a treadmill) at a speed equal to its normal ground speed during takeoff.
busted
First some small-scale tests were performed with a model airplane on a treadmill and the plane was able to take off. For the large-scale test, the MythBusters used a 400 pound ultralight aircraft with a 2000 foot tarp under it. The tarp was pulled backwards to simulate a moving runway. The ultralight pilot had no trouble taking off. This is because the thrust of the airplane engines acts on the air, not on the ground.
http://mythbustersresults.com/episode97
wow, i feel soooo cool...
An airplane cannot take off from a runway which is moving backwards (like a treadmill) at a speed equal to its normal ground speed during takeoff.
busted
First some small-scale tests were performed with a model airplane on a treadmill and the plane was able to take off. For the large-scale test, the MythBusters used a 400 pound ultralight aircraft with a 2000 foot tarp under it. The tarp was pulled backwards to simulate a moving runway. The ultralight pilot had no trouble taking off. This is because the thrust of the airplane engines acts on the air, not on the ground.
http://mythbustersresults.com/episode97
wow, i feel soooo cool...
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Joined: Jun 2005
Posts: 258
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From: Pratt, KS
Originally Posted by crash_lucky13
LOL just saw this on mythbusters.... go figure
An airplane cannot take off from a runway which is moving backwards (like a treadmill) at a speed equal to its normal ground speed during takeoff.
busted
First some small-scale tests were performed with a model airplane on a treadmill and the plane was able to take off. For the large-scale test, the MythBusters used a 400 pound ultralight aircraft with a 2000 foot tarp under it. The tarp was pulled backwards to simulate a moving runway. The ultralight pilot had no trouble taking off. This is because the thrust of the airplane engines acts on the air, not on the ground.
http://mythbustersresults.com/episode97
wow, i feel soooo cool...
An airplane cannot take off from a runway which is moving backwards (like a treadmill) at a speed equal to its normal ground speed during takeoff.
busted
First some small-scale tests were performed with a model airplane on a treadmill and the plane was able to take off. For the large-scale test, the MythBusters used a 400 pound ultralight aircraft with a 2000 foot tarp under it. The tarp was pulled backwards to simulate a moving runway. The ultralight pilot had no trouble taking off. This is because the thrust of the airplane engines acts on the air, not on the ground.
http://mythbustersresults.com/episode97
wow, i feel soooo cool...
Signed, The Naysayers.
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Joined: Sep 2002
Posts: 2,165
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From: Cabot, AR
Originally Posted by Stealth
No, a wee cessna takes off just as easy as a loaded c130, but neither as hard as an f-16. An f-16 is like a rocket with a pilot on it, aerodynamics are not as good.
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From: Burleson, Texas
Originally Posted by Wookie
The type of aircraft has absolutely no bearing on the equation. A Piper Cub flies the same as an A380. Sure the A380 takes more thrust to take off but the equations that govern flight are the same.
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From: Burleson, Texas
Originally Posted by Wookie
The problem is not with the equation, it's the vacuum in your head.
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From: Mount Airy,MD
Originally Posted by jiggle
Take a course in aerodynamics and propulsion systems. Then it will make sense. The airplane flies. Period. It doesn't matter if the wheels are spinning zero, 100 or 1000 mph, nor does it matter which direction the wheels are spinning. What matters is that the engine is pulling (or pushing) against the AIR, not the GROUND. The powerplant would only have to overcome the extra friction from the wheels spinning at a higher rate of speed, but that is negligible.
Last edited by kingfish51; Feb 1, 2008 at 04:58 PM.
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From: Cabot, AR
Originally Posted by Stealth
So, every time I drive the flight line at work and they are engine testing an f-16 or the f-35 that is tethered to the ground and the jet turbine engine is at full throttle and the tethers broke loose the plane would instantly become airborne? I think not, rather, i know not.
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Joined: Nov 2005
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From: Burleson, Texas
Originally Posted by Wookie
Nope, it would start rolling. As it rolls along it will accelerate. Once it accelerates enough it will reach a speed great enough for the wings to produce sufficient lift and the airplane will over power gravity.
Originally Posted by Stealth
Liken the conveyor theory with the engine at full throttle to the plane being tethered to the ground at full throttle. The plane won't fly because it is sitting still.
it doesn't matter how fast the convayor is moving. it can be moving even faster. the thrust will push the plane forward. theres your wind to lift the plane.
Last edited by 06F150STX; Feb 1, 2008 at 05:21 PM.
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From: off the path in Louisiana
Originally Posted by CDB03STX
This is a hopeless case..... Thanks for the MB link...I have to send it to my boss and another freind who is a pilot himself.
Thanks for the MB link...I have to send it to my boss and another freind who is a pilot himself.guys calm down... this is one of the biggest controversies ever...
heck the PILOT of the PLANE for myth busters said there was NO WAY that he would take off... he was more surprised than anyone....
ya'll really need to watch the WHOLE episode...it's really really good.
