saw the show still think they are wrong

Wouldn't be the first time...

oh my ****ing god!

**** THE ****ING PLANE!!!

What he said.....

I did an aeronautics research project in 6th grade, Its HIGHLY amusing to see that almost none of you understand the science behind wing sections, thrust and lift.

lemme try to explain it like this...

nothing ground related can keep the plane from moving.(other than being tied down etc)
think of the wheels as idler pullies for the sake of conversation, or even ball bearings... they just spin/roll and nothing else. The plane will still move forward regardless, and when it does, it will build lift and eventually take off. it will NOT take off from a stationary position, thats whats confusing most of you. but the point is, the "conveyor belt" CAN'T keep the plane from moving forward.

a wing needs a certain amount of air flow over it to create LIFT

Yes and no....your correct, but thats only half the reasons. The profile, AOA, and air speed are equal contributors. BUT the profile of a wing determines how much lift can be created, and the determines how that is distributed accost a wing section. If you have a wing thats profiled like a long teardrop and is fully symmetrical, it will be efficient at high velocity and allow lift to be achieved either upside down or right side up, making that Ideal for high speed fighters. A fully symmetrical tear drop profile that is more stout shaped, will allow for max lift at a lower velocity and create lift any orientation, making it ideal for prop engine stunt planes. An in betwine profile would be used for a pylon racer.

Asymmetrical wing sections create immense amounts of lift but only when they are right side up. These type of wings are used for Cargo, and ultra lights. Now the Mythbusters used an ultra light which has a stout wing section and is asymmetrical creating sufficient lift at very low speed.

AOA is angle of attack. that has more to do with props that wings but its the same principles at work.

you are ALL missing the point, the shape of the wing has nothing to do with it. Lift will come as the plane moves forward.....

and the plane will move forward because NOTHING wheel related can hold it.

*sigh*... lemme try another more simple explination...
you are stuck in a fast moving river... you kick you're feet and legs as fast as you can yet you get no where... but then you grab onto a branch/root hanging right above the water... you use both arms to pull your way up and along the branch upstream, no matter how much the stream speeds up an flows faster, you still can pull you way upstream with you arms(granted you're not a weakling) in this your legs are the planes wheels, usless, and your arms are the propellers, the branch is the air the propellers "grab"...

...let me know that this got through to at least 1 person....

You got through to at least one person. :lol:

At this point this is like politics, nobody is changing anyone else's mind.

an even better example would be a sail boat moving against the current. if you don't get it after that, then you suck.

I know exactly what you are saying, I've been into aeronautics for a long time...I'm was just saying that the shape of the wing determines a lot about lift not about if it would take off or not. Some body said air speed and I was saying thats only a small part...I'll think you kinda missed that

then they are asking the question wrong

The question is what it is.

i don't think that is so much true as that people are interpretting it wrong. if you misinterpret the problem there is no way you can arrive at the proper solution.

so basically it comes down to people have no freaking idea how a plane works and can not comprehend the fact that no mater how fast the conveyor moves the air is still not moving. being that a plane creates thrust against the air... this is what happens when certain people think about this ------->:drool:

This will solve the problem real quick...

http://www.defenseindustrydaily.com/..._Firing_lg.jpg

Or how about this?

http://blog.800hightech.com/wp-conte...-avenger-1.jpg

pauls explanation makes sense. read that

or yes, shoot the plane down.

oh wait, itll never take off, how silly of me!

no.

but some are over-thinking it and bringing all types of irrelevent things into the argument. basically, what you have is a stationary object. no matter what kind of thrust is made by the propellers or the jet engines, if you prefer, there is no way a stationary object can achieve flight. it can't be done, no matter what type of aeronautics you bring into the equation, it all boils down to a stationary object (which is what you have, because the conveyor is negating forward movement) cannot take off.

it wouldn't matter if you had the most perfect wing proportions, the perfect teardrop that would be best suited to get the most lift, because the plane is not moving. it doesn't matter what engine you use to try to move the plane, because the conveyor is negating forward movement. while you can't stop the engine from achieving maximum thrust unless you cut off its air supply, it still doesn't matter because the plane is not moving forward. in order to achieve flight, air must pass over the wing. if the plane is not moving, then there is no wind passing over the wing.

now, i could sink to the level of the most obnoxious in this thread and start calling people stupid, and what-not, but i won't. what i want you to think about is not the wing shape, nor the amount of thrust the engine can make, nor if it's using propellers or a jet engine, nor what type of tire it's using... what you need to think about is that the conveyor is matching the speed of the plane's forward movement, which means the plane is not moving forward. other than the harrier jump-jets, i don't know if a plane in existance that can take off from a stand still, which is what you have here. tell me i got through to one person.

http://txfx.net/2005/12/08/airplane-on-a-conveyor-belt/
http://www.straightdope.com/columns/060303.html

:dancinglock:

We can take care of it on the ground too.

This:
http://www.baseops.net/militarybooks/rangers6.jpg

+ This:
http://www.mainandcentral.org/home/m...anian%20C4.jpg

People are confusing the fact that the convery belt is counteracting the speed of the WHEELS and not the speed of the PLANE.
Plane will move foward, as it develops more and more thrusts from its engines. The wheels and belt are meaningless.

No.

From what I undestand... plane wheels are free-rolling and not powered.

For example, put a car on the treadmill, and it will go nowhere, because the wheels power it and make it move.

In a plane... the wheels do not power it... they're basically just padding so the fuselage isn't sitting on the ground. So the wheels kinda don't do anything in that regard.

wow, you typed something. I was completely expecting to see "F the Plane"

so the plane continues to move forward regardless of how fast the conveyor belt runs?

that's the part i have a problem with. the OP states that the conveyor will go backward at the rate of speed the plane moves forward, in which case the wheels will be spinning at least twice as fast as the conveyor... but the plane will not move forward.

The belt spins as fast as the wheels.

One of those links was pretty good. If you got onto a tredmill with roller blades, and were pulling on a rope that is attched to the wall in front of you, wouldnt you move foward? Eventually, the force foward of the thrust will overcome the backwards force of the belt tot he wheels.

Plane takes off due to the fact that the plane is moving foward, and thats what confuses people. The plane is moving foward due to the fact that the engines are producing thrust, not the wheels.