Depends on the speed. If it gets enough speed it's still going to lift off isn't it, regardless of the ground.
It isnt going to be moving as it will be on the same point in a tredmill. So the wings wont generate any lift. If this worked why wouldnt they use this at airports on small (relative to a landing strip) tredmill rather than have massive runways. Just realised they still have to land. But im still relativly sure on my answer.
Hmm, I dunno, certainly interesting. I don't think it's viable for the plane to stay on, would be way too hard, which is why they use normal run ways. Ahhh, well, I think after the speed got high enough, it would go up, but would actually come back down wouldn't it, because it has no forward thrust. So it would go up, but come back down again because it's not actually moving forward. So no it wouldn't take off.
isn't it simply staying in the same place, just it's engine going faster and it's wheels spinning faster?
dont think it would lift. Because it need uplift from air resistance under the wings of the plane. basicly wat DrSiN sed. thats how i see it :smile:
Yea, it's in the place place, as if it's standing still, so it's not going anywhere. May as well have the treadmill turned off.
Actually, the real answer is yes. It will take off providing the treadmill strip is long enough (length comparable to a runway will do). Otherwise the plane will drop off the treadmill when it uses up the available "runway"... Why? Because the wheels on the plane are freewheelling units - they are not a factor in the movement of the plane, so the jet engines will be actually thrusting the plane forward, even if the treadmil speed is reaching enourmous RPMs, the plane will go forward due to momentum and thrust. This is coming from a true pilot (me), so i guess you can say with a confidence that it's certainly true.
Nope. Thrust from the engine is made null by the treadmill, so the plane is not moving, therefore has no lift. Edit: posts below are correct - wheels/treadmill are irrelevant :x
I don't think they want you to get hugely technical and if's and maybes. If the plane is going forward at 500km/hr, and the treadmill is going backwards at 500km/hr, it's standing still, so it's not moving, doesn't have any lift, or any wind on it, so it's not going anywhere. I mean, in reality, it wouldn't be like that, there's a huge number of factors to take into consideration, but in perfect world and question, it's not moving, hence no lift, no speed, no take off.
Uh, the engine is pushing the jet forward but how does it go forward? Through the wheels. I mean if the wheels weren't there the engine would be trying to move the bottom of the plane which is being scraped along the ground. So with the wheels on the treadmill the turbines or whatever can push the plane all they want, but whatever velocity the plane is supposed to have gets canceled out by the treadmill. Right? If this is the case the plane is just sitting there trying to thrust itself forward but the contact between the wheels and the treadmill make it just sit there. o.o
Ground speed means nothing to the plane, so the treadmill cannot nullify the thrust from the engines. Simple fluid dynamics - wheels can even turn backwards, but the plane will be thrusted forward, no matter what the treadmill does... freewheeling units, remember?
but both speed the one from the plane and the one from the treadmilla re the same so theres no acceleration cause they both cancell out the plane will stay there forever or until the fuel runs out
Read my lips: You can't cancel the acceleration of a jet propelled plane. If the plane was moving like a car, with a shaft connecting the engine power to the wheels, yes, you can cancel the speed by moving the ground in the opposite direction. But in a jet (or rocket) propelled plane, wheels can turn anywhere you like, the plane will still gain speed and be pushed forward by the engine produced thrust.
Yes, if there were no wheels, than the treadmill will push the plane in oposite direction and the engines will force the fuselage to be scrapped along the ground. But since the plane has wheels, the ground speed is not a factor.
Ok everyone, i suggest you conduct an experiment: Take a car or plane model and put it on a cloth covered table. Now, ask someone to move the cloth in one direction, while you push the car in another. You will notice that the moving cloth will spin the wheels very fast, but you will still be able to push the car forward with ease... well, that's the whole point of this.
