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This is dumb. Planes are not cars.
jus' askin'...
That's more or less what a kite does, so yes.
I said maybe.....
Whatever the weight
On flap 20, the speed will be lesser but the poz climb rate will be slower.
On flap 10, the speed needed is greater, and therefore climb rate higher.
At 20, the stress on the landing gear is lesser and so is the noise.
So, technically, if the headwind was a mighty 180 mph, the plane would need to be tethered to the ground.
An unladen 747 would need less. c. 140kts I believe.
Yes, I'm plane anorak.
*An Official Foo-Approved guitarist since Sept 2023.
No airflow over the wings. No Bernoulli effect. No lift.
I’m so bored I might as well be listening to Pink Floyd
600m take off.
Compare this with Joburg where a fully laden 747 will take 3000m to become airborne.
*An Official Foo-Approved guitarist since Sept 2023.
For there to be any net forward motion relative to a stationary observer, the wheels must implicitly be rotating at a faster speed than the conveyer. This is the case regardless of whether power is being delivered through the wheels, or in this case, through the jet engines.
This more of a thought experiment more than a realistic situation because in reality, it is impossible to create such a conveyer belt that precisely and instantaneously matches the speed of the wheels. However, should such a belt exist, the plane would be kept stationary by the belt through the frictional forces between the belt and the wheels and the wheel bearings, creating a resistive force that matches the thrust delivered by the engine. In reality the wheels would have to be spinning so fast for this to happen that they would probably fail and disintegrate quite quickly as the engine power is increased, putting an end to the experiment, and the plane itself.
Wheel and bearing drag will be small in comparison to thrust available from the engines. What limits an aeroplanes ability to take off is relative windspeed over the aerofoil sections.
Since the conveyor belt has no influence on the windspeed (except in the boundary, probably millimetres) and wheel drag is proportional to conveyor speed the aeroplane will move forwards relative to the ground.
Since at the start the thrust will exceed the combined drag of the wheels and win, it will accelerate up to the point where thrust <= air drag + wheel drag. Before this point the forward ground speed will exceed the speed required to generate sufficient lift to take off and wheel drag will cease to influence the equation.