Can a Plane on a Treadmill Take Off?

"Damian" wrote in message
...
Paul...dont look now, but that airplane is NOT flying off the ground until
the AIRSPEED is up...the treadmill is only moving the TIRES, that means
diddly squat to an airplane.

Damian, don't look now but Paul is exactly right (except for his rude
nature, of course).

The treadmill is irrelevant to the airplane's motion. If the airplane is
stationary on the treadmill, it's because it has a headwind the same speed
as the treadmill and enough thrust to fly into the headwind at the same
speed as the treadmill. Of course, the wheels will be turning on the
treadmill, but only because the treadmill is rotating them against the
air-based stationary nature of the airplane.

Without a suitable headwind for the airplane to fly into, the treadmill
would just push the airplane backward. Airplanes don't use their wheels for
transmitting power to forward motion (most don't, anyway ).

Pete

Peter, I think you lost the relative perspective. Given the original riddle,
the treadmill only moves backward at the same rate the plane moves forward.
If the plane was developing exactly enough thrust to counteract the
headwind, it will not move and neither will the treadmill.

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Travis
"Peter Duniho" wrote in message
...
"Damian" wrote in message
...
Paul...dont look now, but that airplane is NOT flying off the ground
until the AIRSPEED is up...the treadmill is only moving the TIRES, that
means diddly squat to an airplane.

Damian, don't look now but Paul is exactly right (except for his rude
nature, of course).

The treadmill is irrelevant to the airplane's motion. If the airplane is
stationary on the treadmill, it's because it has a headwind the same speed
as the treadmill and enough thrust to fly into the headwind at the same
speed as the treadmill. Of course, the wheels will be turning on the
treadmill, but only because the treadmill is rotating them against the
air-based stationary nature of the airplane.

Without a suitable headwind for the airplane to fly into, the treadmill
would just push the airplane backward. Airplanes don't use their wheels
for transmitting power to forward motion (most don't, anyway ).

Pete

"Travis Marlatte" wrote in message
hlink.net...
Peter, I think you lost the relative perspective.

No, I didn't.

Given the original riddle, the treadmill only moves backward at the same
rate the plane moves forward.

The rate at which the treadmill moves is entirely irrelevant. An airplane
does not transmit any force through it's wheels. They simply rotate
whatever speed is required to account for whatever speed the airplane has
relative to the surface the wheels are in contact with.

It doesn't matter one bit WHAT speed the treadmill moves, according to the
original riddle or otherwise.

If the plane was developing exactly enough thrust to counteract the
headwind, it will not move and neither will the treadmill.

The headwind is just an example. The actual wind could be anything. Yes,
if the headwind is exactly the same speed as the airspeed, the airplane
won't move. My only reason for setting the headwind equal to airspeed, as
an academic point of reference, is that if it's not, the airplane isn't
going to stay sitting on the treadmill for very long, making the "riddle"
even less interesting.

Pete