dirtehscandi
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Apparently this is a banned discussion on xkcd...I think no due to the lack of airflow over the wings resulting in zero lift. @MisterSavage and his team tested this with a prop-driven plane but the movement of the prop created the required airflow over the wings...
apt311
Yes. Unlike a car, the engines provide thrust against the air - wheels are free-spinning so they can be effectively ignored.
GoToQuirkProviderZooeyDeschanel
I think the answer's "no". The plane uses its engines to move forward, generating lift.
SearchingForUnderstanding
So, posting third grade standardized test questions is what you think passes for content these days?
TheGreatCO
It will take off, the wheels will just be spinning twice as fast, but they don't propel the plane so that doesn't really matter.
Arjinify
But the conveyer belt matches the speed of the wheels so the plane can never move
cheesywonton
True
apt311
Exactly
BananaShip
It depends though, if you get a conveyor belt long enough the boundary layer could eventually reach the wings.
BananaShip
If your wings are low enough to the ground, you could generate lift even with a jet engine.
BananaShip
Even if you could build a hypothetical track that would always keep the landing gears from moving forward.
HartoftheForest
I'm gonna say no, but I'm not a physics major.
sosofosho
It's not the prop's airflow that made the plane take off. The plane was moving forward, so, normal flight conditions.
sosofosho
The Mythbuster experiment just tested whether or not the plane could achieve forward airspeed on a conyeor.
esheikamiasiouri
It will not take off. Planes take off because of the pressure differential of the moving air due to the shape of the wings.
Astranolus
The prop is in front of the plane, pushing the wind back over the wings. Jet engines are under the wings, no lift generated on the wings.
cheesywonton
False
imsam77
...if the plane wasn't moving relative to the earth, it wouldn't takeoff...if it did, it's voodoo.
apt311
Doesn't matter if props or engines, still thrust generated.
Astranolus
this is true, but do 747 engines combined produce more thrust than the weight of the plane?
Astranolus
Nevermind, no.. its apparently a .27 thrust to weight ratio. Still no take off
risperidone
Airspeed is everything for a plane. ..if it's too low the plane stall and fall. So,do you see air mooving under the wing in your experiment?
Legdig
Yeah, you need the high pressure air under the wings to gain lift. or was it the other way around?
dirtehscandi
Yup! High pressure below, and low pressure above!
Legdig
Thanks! Say, I bet you could do this with a helicopter.
UngratefulNoob
Except wouldn't the helicopter fly off the back of the conveyor belt...?
Legdig
Well, if the conveyor is going the same speed, it would likely stay still.