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Old December 12th 06, 02:09 AM posted to rec.aviation.piloting
Peter Dohm
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Posts: 1,754
Default So...about that plane on the treadmill...


"Peter Duniho" wrote in message
...
"FLAV8R" wrote in message
...
That would depend on what has the greater resistance,
the air in front of the plane or the belt on the treadmill.


No, it would not depend on that at all. Both of those effects are

creating
a resistance in the same direction, and thus are additive. Which one is
greater is irrelevant. The only relevant question is whether they

combined
exceed the thrust from the engines.

They don't even come close to doing that, and so the engines can easily

push
the airplane forward to a high enough speed for flight.

[...]
You can equate it to an airboat in a river.
Will the river push the airboat down stream or
will the propulsion of the engine move it forward?


It's similar, yes. Except that the drag due to friction from the

treadmill
is miniscule, whereas hydrodynamic drag is significant.

Pete


As pictured, the runway is much to short, which is just as well since the
uprights of the treadmill would impinge on the wings. bfg

Actually, I agree that the drag from the treadmill is trivial. Therefore,
if sufficient distance was provided to accellerate to an appropriate
airspeed, the only problem would be the maximum speed rating of the tires.

Peter