Quote:
Originally Posted by Turbo Ghost
Alright, let's try to get this cleared-up.
If I put a treadmill in front of a wall and told you to run on it, would you say "NO! I'll hit the wall!"?? Of course not! Your body would be STATIONARY while running on the treadmill! THIS is the whole basis of the treadmill/plane concept. The propeller DOES NOT make the plane fly! Airflow over the wings is what creates lift. The propeller only moves the plane forward so that air moves over the wings which provides the lift to get the plane airborne. If the plane isn't moving (which it is not because it is on a treadmill!) it has no lift!
If you had a glider which is simply an airplane without a motor and you put a giant fan in front of it that could provide enough airflow for lift, it would lift off the ground BUT, it wouldn't move forward! It has no prop therefore it has no forward motion.
So, here's the bottom-line! If a plane is on a treadmill, it is stationary. A stationary plane does not fly! UNLESS, you perform this test during a tornado or hurricane in which the windspeed surrounding the plane is sufficient to provide lift.
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1) The spinning prop generates forward motion and the wings provide the lift as the air moves over them.
Do you agree?
2) Lets pick a forward speed of 50 mph that generates enough lift for the plane to "have the opportunity to become airborne".
Agree with statement 2?
3) The big treadmill has a belt speed of 60 mph. If they plane had it's brakes applied, it would be moving backwards at 60 mph.
3A) Since the brakes are not applied, the wheel are moving "backwards" at 60 mph. ( let's pretend somebody is at each wingtip holding the plane in place,
only to prevent backwards movement ) The pilot applied throttle and the plane moves forward. Once he gets to 50 mph , the wheels are moving the equivilent 110 mph and the plane becomes airborne.
edit, added the bold wording for clarity