Two Wheel Fix - Plane on conveyor... Will it ever take off?

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Quote:

Turbines pull air over the wings which aids in lift. How much I don't know.

I'm sure if you reached the 175mph and stopped the engines the plane wouldn't lift. You would have to increase speed. But yes air moving across the wings is the only thing lifting the plane, but we are discussing how that air gets moving.

The part your missing is the belt would not be able to hold the plane in place because the plane moves through air no matter what the wheels are doing.

Quote:

Originally Posted by HRCNICK11 (Post 243564)

The part your missing is the belt would not be able to hold the plane in place because the plane moves through air no matter what the wheels are doing.

Yeah, maybe ur right. At 175mph is doesn't matter what is happening to the engines...the 175mph is what the engines are giving out regardless if something is pushing it, pulling it whatever.

Quote:

Originally Posted by 101lifts2 (Post 243562)

Dude, seriously!?!?! Where do you come up with this stuff??

No, the turbines do not move the air across the wings. Generally they're mounted UNDER the wings, and the outlet is BEHIND the wings. Some are even mounted in the back. Or how about a small plane with a single prop in front... how is that gonna move any are across the wings?? It's not even close

I don't know where you got this wacky idea that the engines are like a fan blowing air across the wings. THEY'RE NOT!! They have one purpose and one purpose only.... to move the plane forward. That is IT! Once the plane is moving forward, the surrounding air moving across the wings produces the lift

But since you want to argue.... by your logic, explain to me how this plane ever made it off the ground. Where's the turbines drawing the air across the wings?? Hmmmmm....

http://www.richard-seaman.com/Aircra...erburner_1.jpg

Seriously bro.... not trying to sound like a dick here or anything, but you might want to educate yourself a little bit on the subject matter before getting into an argument.... just sayin ;)

Quote:

Originally Posted by thirdgenlxi (Post 243569)

Read my post above snappy. And I never said the turbines are needed to lift a plane, I was simply saying that the air the turbines draw across the wings aid to the lift. 1% maybe:lol

If you strapped the plane down from the top and put it on a scale, spun up the turbines at full pop, would the plane weigh any less? If so, then there is some lift acting on the wings. Speaking of commerical jets with the turbines under the wings.

Quote:

Originally Posted by 101lifts2 (Post 243546)

Its the combination of the thrust of the engine (jets moving air which goes over the wings) and the air velocity at 175mph (air moving over the wings) COMBINED that moves the plane. Yes if the engine jets were big enough, the plane would move w/o the air velocity of the moving plane. Its like how do you turn a bike fast. You do A PLUS B. Countersteer and lean. Can you still turn w/o leaning? Yes, but is takes much more force.

Add you'd still have that. The wheels do not power the plane. The engines would get it up to speed regardless of what the wheels were doing.

Quote:

Originally Posted by Homeslice (Post 243572)

That's a sweet pic

Not as sweet as this one! heheheh

http://www.aviationexplorer.com/Comm...fterburner.jpg

Quote:

Originally Posted by Rider (Post 243573)

Add you'd still have that. The wheels do not power the plane. The engines would get it up to speed regardless of what the wheels were doing.

Agree...the wheels would just spin at the ground speed plus the conveyor speed. Never argued against it. They can be neglected.

At least I'm smart enough to know when I'm stupid....:wink:

An Airplane does not need "propulsion to fly.
It needs airflow over the wing surfaces.

If you want aircraft to fly, you do not need ground speed...you need airspeed.

Simple way to show this is to stick a paper airplane in front of a fan.

Propulsion's purpose is to maintain airspeed (to over come aerodynamic drag) necessary to ensure lift.
In the case of a glider, gravity is used to achieve proper airspeed (once disconnected from the tow aircraft and aerodynamics take over.

A helicopter use the same principle with rotor hub altering the angle of attack during each rotation as the rotors experience vary airspeed.

You can get into more detail of aerodynamic (vortex crap, drag)

The key to creating lift is the negative pressure on top of the wing with some positive pressure under neath

Official NASA yapping

Quote:

Lift is the force that directly opposes the weight of an airplane and holds the airplane in the air. Lift is generated by every part of the airplane, but most of the lift on a normal airliner is generated by the wings. Lift is a mechanical aerodynamic force produced by the motion of the airplane through the air. Because lift is a force, it is a vector quantity, having both a magnitude and a direction associated with it. Lift acts through the center of pressure of the object and is directed perpendicular to the flow direction. There are several factors which affect the magnitude of lift.

HOW IS LIFT GENERATED?

There are many explanations for the generation of lift found in encyclopedias, in basic physics textbooks, and on Web sites. Unfortunately, many of the explanations are misleading and incorrect. Theories on the generation of lift have become a source of great controversy and a topic for heated arguments. To help you understand lift and its origins, a series of pages will describe the various theories and how some of the popular theories fail.

Lift occurs when a moving flow of gas is turned by a solid object. The flow is turned in one direction, and the lift is generated in the opposite direction, according to Newton's Third Law of action and reaction. Because air is a gas and the molecules are free to move about, any solid surface can deflect a flow. For an aircraft wing, both the upper and lower surfaces contribute to the flow turning. Neglecting the upper surface's part in turning the flow leads to an incorrect theory of lift.

NO FLUID, NO LIFT

Lift is a mechanical force. It is generated by the interaction and contact of a solid body with a fluid (liquid or gas). It is not generated by a force field, in the sense of a gravitational field,or an electromagnetic field, where one object can affect another object without being in physical contact. For lift to be generated, the solid body must be in contact with the fluid: no fluid, no lift. The Space Shuttle does not stay in space because of lift from its wings but because of orbital mechanics related to its speed. Space is nearly a vacuum. Without air, there is no lift generated by the wings.

NO MOTION, NO LIFT

Lift is generated by the difference in velocity between the solid object and the fluid. There must be motion between the object and the fluid: no motion, no lift. It makes no difference whether the object moves through a static fluid, or the fluid moves past a static solid object. Lift acts perpendicular to the motion. Drag acts in the direction opposed to the motion.

You can learn more about the factors that affect lift at this web site. There are many small interactive programs here to let you explore the generation of lift.