Can a Plane on a Treadmill Take Off?

Thomas Borchert wrote:

Alexy,

The conveyor is programmed to move in such a way as to maintain the
aircraft at an airspeed of zero as measured at the pitot.

Absolutely, if you CHANGED the problem, and restated it as above, then
it wouldn't fly.


Actually, you couldn't do that - which is another point the question
makes.

True, from a practical standpoint. As far as the thought experiment
goes, you could if the conveyer moved fast enough that the rolling
friction of the tires plus the bearing friction of the wheels exactly
offset the thrust of the plane's propulsion system. My initial
calculations indicate that the speed needed for that to happen is
somewhat below the speed of light, but significantly beyond the speed
at which the wheels and tires would disintegrate. g
--
Alex -- Replace "nospam" with "mail" to reply by email. Checked infrequently.

Alexy,

My initial
calculations indicate that the speed needed for that to happen is
somewhat below the speed of light, but significantly beyond the speed
at which the wheels and tires would disintegrate. g


Concur. g

--
Thomas Borchert (EDDH)

alexy wrote:
Thomas Borchert wrote:

Alexy,

The conveyor is programmed to move in such a way as to maintain the
aircraft at an airspeed of zero as measured at the pitot.

Absolutely, if you CHANGED the problem, and restated it as above, then
it wouldn't fly.


Actually, you couldn't do that - which is another point the question
makes.

True, from a practical standpoint. As far as the thought experiment
goes, you could if the conveyer moved fast enough that the rolling
friction of the tires plus the bearing friction of the wheels exactly
offset the thrust of the plane's propulsion system.

The question, though, says that the wheels are built to take it. They
must have frictionless bearings. g

It only says that they can take it. It doesn't say why. My plane lifts off
at 60mph. I'm sure the bearings and wheels would handle 120mph but they
aren't frictionless.

--
-------------------------------
Travis
"cjcampbell" wrote in message
ups.com...

alexy wrote:
Thomas Borchert wrote:

Alexy,

The conveyor is programmed to move in such a way as to maintain the
aircraft at an airspeed of zero as measured at the pitot.

Absolutely, if you CHANGED the problem, and restated it as above, then
it wouldn't fly.


Actually, you couldn't do that - which is another point the question
makes.

True, from a practical standpoint. As far as the thought experiment
goes, you could if the conveyer moved fast enough that the rolling
friction of the tires plus the bearing friction of the wheels exactly
offset the thrust of the plane's propulsion system.

The question, though, says that the wheels are built to take it. They
must have frictionless bearings. g