son of a ..... just let it die already...

[Rob WS6]

Oh christ. Im still in shock that these ****IN MORONS dont see why the plane WILL take off!! Are people that ****ing retarded that they cant see the simple laws of physics and logic? ARGH!!!!!

[Knipps]

Originally Posted by Rob WS6

Oh christ. Im still in shock that these ****IN MORONS dont see why the plane WILL take off!! Are people that ****ing retarded that they cant see the simple laws of physics and logic? ARGH!!!!!

& what might those be?

[j0n]

Originally Posted by Chevelle 454

& what might those be?

yea im curious as well rob...seeing as how the plane MUST have ground speed in a situation where there is neither a head nor tailwind in order to have airflow over the wings(which is the only way an airplane will generate lift). Since the conveyor belt will cancel out any and all ground speed, there is ZERO airflow over the wings generating ZERO lift leaving the plane to sit in one spot and fry the wheel bearings

[johnjzjz]

Its all about lift --air speed over and under the wings -- thrust moving foward is what gets you that --tread mill is like ice for drive wheels -- it will never get the nessessary air to lift the craft -- jz

[johnjzjz]

hahahahahahahah unless its a Marine corp Harrier vertical jet --- jz

[Untamed]

I second the notion of sending it in to Mythbusters.

[johnjzjz]

after thinking about it again it would depend on wheir the thrusters were on the tail or under the wings -- on the wings would create an air cushion -- and like a harrier will lift up -- WW2 pappy boington famous overstocked air craft carrier comes to mind -- he flew a mc donald douglass bomber off the deck of an aircraft carrier fully loaded for a bomming mission on japon -- the nose of the bomber was 20 foot back from the the end of the deck of the aircraft carrier -- its all about the lift not the foward speed --- jz

[Tsar]

god some people lack brain

What I learned from Old Hack was that an updated version of a question aimed at confusing folks over relative measurements of airplane motion and the medium in which it operates had shown up on the Internet, and it was causing the fracas in the Lounge.

The question that has been going around is not particularly artfully worded, and I think that has caused some of the disagreements, but I'll repeat it as it is shown: "On a day with absolutely calm wind, a plane is standing on a runway that can move (some sort of band conveyor). The plane moves in one direction, while the conveyor moves in the opposite direction. The conveyor has a control system that tracks the plane speed and tunes the speed of the conveyor to be exactly the same (but in the opposite direction). Can the airplane ever take off?"

My comment: Notice that the question does not state that the conveyor's movement keeps the airplane over the starting position relative to the ground, just that it moves in the direction opposite to any movement of the airplane.

Initially, about a third of the folks here said that the airplane could not ever takeoff, because the conveyor would overcome the speed of the airplane and it could never get any airspeed. The rest said the airplane would fly.

The "It won't fly, Rocky" group said that the conveyor would hold back the airplane. They asked us to imagine a person running on a treadmill. As he or she sped up, the treadmill would be programmed to speed up, just as the conveyor in the problem, and the person would remain over the same locus on the earth, while running as fast as possible.

The argument was that if the airplane started to move forward, the conveyor program was set up to move the conveyor at exactly that speed, in the opposite direction, thus, the airplane would never move relative to the ground, and, because the air was calm, it could never get any wind over its wings. One of the analogies presented was the person rowing at three mph upstream in a river on a calm day. However, the current was flowing downstream at three mph, so the resultant speed with reference to the stream bank and air was zero, and thus there was no wind on the rowboat.

I watched and listened to the disagreement for a while and was fascinated to see that the argument seemed to split between those who had some engineering or math background, all of whom said the airplane would takeoff and fly without any problem; and those with some other background, who visualized the airplane as having to push against the conveyor in order to gain speed. Because the conveyor equaled the airplane's push against the conveyor, the airplane stayed in one place over the ground and in the calm air could not get any airspeed and fly.

It was an interesting argument, but as things progressed, more rational heads prevailed, pointing out that the airplanes do not apply their thrust via their wheels, so the conveyor belt is irrelevant to whether the airplane will takeoff. One guy even got one of those rubber band powered wood and plastic airplane that sell for about a buck, put it on the treadmill someone foolishly donated to the Lounge years ago, thinking that pilots might actually exercise. He wound up the rubber band, set the treadmill to be level, and at its highest speed. Then he simultaneously set the airplane on the treadmill and let the prop start to turn. It took off without moving the slightest bit backwards.

http://www.avweb.com/news/pilotlounge/191034-1.html

[Tsar]

http://www.youtube.com/watch?v=IZGdUAiMcPs

[Knipps]

Originally Posted by Tsar

http://www.youtube.com/watch?v=IZGdUAiMcPs

that made 0 sense...

[Tsar]

Originally Posted by Chevelle 454

that made 0 sense...

tread mill + remote control airplane with fan "turbines"= lift off...

[Knipps]

Originally Posted by Tsar

tread mill + remote control airplane with fan "turbines"= lift off...

sure it was r/c? there's always something moving at the top of the screen w/ it..
does it really matter?

[Tsar]

Originally Posted by Chevelle 454

sure it was r/c? there's always something moving at the top of the screen w/ it..
does it really matter?

yes it was an RC airplane. Which acts like a real airplane.... PEOPLE WHEELS ON AN AIRPLANE HAVE NOTHING TO DO WITH ITS SPEED. ITS NOT A CAR! Engine thrust has NOTHING to do how fast the wheels will move. Engine thrust pushes the airplane thru the air regardless of how fast the, FREE SPINNING, wheels are moving. Just like the article said the wheels will move twice as fast and the airplane will take off like nothing was wrong.

[DieselKickYoAss4Sure]

Originally Posted by Chevelle 454

www.tubgirl.com

click it if you dare

I just threww up a lil BIT

[DieselKickYoAss4Sure]

an airplane dose not need speed to take off the Propeller creates a vacume in front of the plane and pressure behind and theirfor nothing to do with speed of the wheels it will take off as long as you get hte wheels the slightest bit off the conveyer! it will then go forward! Even if the wheels didnt come up a little it would still fly cus well THERE ARE WHEEELS ON THE PLANE! WHeels spin the palne would jus tgo forward as it normally dose!

[ChickenLittle]

who gives a ****?

[Teds89IROC]

Originally Posted by johnjzjz

--tread mill is like ice for drive wheels --

yes, if the plane used drive wheels

[GP99GT]

the plane can take off, end of thread, lockplzkthx

[unstable bob gable]

[Ian]

the plane will in fact take off.

[Tsar]

Originally Posted by Ian

the plane will in fact take off.

welcome to post number 5

[V]

before the original thread in the lounge was deleted, i believe i was one of the first to say it will take off, but noooooooooo, some people thought they knew more. anyways, the plane will live on forever, F'd or not.

[Kojak]

Originally Posted by Chevelle 454

wow.. still unlocked/here

mythbusters needs to get their hands on this, the only thing is it big enough for them?

And IMO it will take off under normal circumstances...

[johnjzjz]

Originally Posted by Teds89IROC

yes, if the plane used drive wheels

i was looking at it as it would nagate the treadmill

[NJSPEEDER]

not going through this again

/thread