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Will it take off?


Coytee

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Even if the conveyor goes faster than the plane, which at first it does, the plane overcomes the very slight added friction at its wheels and accelerates through the air. The conveyor does not affect the air which is still motionless that the plane uses to accelerate (not its wheels).

A plane does not use its wheels to accelerate, however if it did then yes it would be a different outcome.

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Put more friction on the plane's contact to the conveyor and use ski skids no wheels.

The skids would likely even prevent a plane from flying even on a typical runway without the conveyor.

However a planes wheels are free floating and have little impact on its acceleration speed which it gets through the air by propeller or jet. So while the conveyor will make the planes free floating wheels need to spin faster, the plane will still accelerate and then fly through the air.

I watched the entire Mythbusters episode and with both model scale and the real plane the conveyor had no effect at all on the planes ability to fly.

Put more friction on the plane's contact to the conveyor and use ski skids no wheels.

The skids would likely even prevent a plane from flying even on a typical runway without the conveyor.

However a planes wheels are free floating and have little impact on its acceleration speed which it gets through the air by propeller or jet. So while the conveyor will make the planes free floating wheels need to spin faster, the plane will still accelerate and then fly through the air.

I watched the entire Mythbusters episode and with both model scale and the real plane the conveyor had no effect at all on the planes ability to fly.

Wheels still create friction and you can still keep the plane motionless at uncomprehensible speeds of the conveyor.

You have to realize that this scenario is hypothetical and mythbusters could never recreate the speed necessary to

make this work.

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Wheels still create friction and you can still keep the plane motionless at uncomprehensible speeds of the conveyor.

You have to realize that this scenario is hypothetical and mythbusters could never recreate the speed necessary to

make this work.

The original question is that the speed match that of the plane, which Mythbusters did. The plane easily overcame the speed of the conveyor and once the plane overcomes the conveyor the friction becomes almost zero so the added speed the conveyor produces is no longer a force against it no matter how fast the conveyor travels. The plane engines which use air not wheels overcomes the slight friction the wheels add.

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Some people just can't see that it makes no difference what surface the aircraft sits on, the wheels don't drive or provide forward motion to the aircraft so it makes no difference if the aircraft sits on the ground, ice, snow, water, aircraft carrier or conveyor belt, the aircraft will acclerate and take off normaly.

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One more try: the plane is not prevented from moving. The plane is also not wheel driven, it's propelled by its propeller, jet or rocket engine or whatever.

If you, the observer, are standing to the right side of the plane, it will be travelling toward the right, while the conveyor moves toward the left. If you look at the Mythbusters video on Youtube, that's what you'll see.

Since the conveyor's speed matches the ground speed of the plane, the only thing the conveyor does is cause the plane's wheels to spin at double the ground speed of the plane. It does not affect its ability to fly, so the plane takes off as it normally would, although its wheels are spinning twice as quickly as usual.

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Sorry to change the topic but can't we quit beating this poor abused dead horse and debate something really important.

I mean come on.

We all deep down know the earth is flat but have caved to those who think it's round and sperical. Let's all join The Flat Earth Society and quit lettin' those crazy scientists control our thinkun.

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My premise is that by matching the plane's speed it means to keep the plane from moving forward in space. Due to the fact that wheels

have a coffieient of drag(the ratio of the drag on a body moving through air to the product of the velocity and surface area of the body, then
a conveyor moving at unimaginable speeds could keep the plane from foving forward in space. Taking that scenario the plane would not move
untill the conveyor got to the speed of light then the plane would be able to move forward. Just a matter of what is meant by matching the
planes speed to me it meant to keep it from moving forward in space.
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It appears that you may have mis-read the original statement. A number of people seem to overlook the ability of the plane to move, although it's clearly stated in the second sentence.

From the first page, back in 2006, the original quote:

a plane is standing on a movable runway( something like a conveyor).as the plane moves the conveyor moves but in the opposite direction.the conveyor has a system that tracks the speed of the plane and matches it exactly in the opposite direction.

the question is

will the plane take off or not?



Note where it says "as the plane moves". If the plane is moving north (for example) at 50mph, the conveyor will be moving south at 50mph. The plane's wheels will be spinning at 100mph. That does not matter, because the plane is not wheel-driven. The moving conveyor will not prevent the plane from moving or from taking off once it reaches takeoff speed.

According to your premise, if the wheel drag was sufficient, when the conveyor reached a certain speed, it would begin to to slow the plane and eventually start to drag the plane backwards. However, the plane would take off long before that.

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My premise is that by matching the plane's speed it means to keep the plane from moving forward in space. Due to the fact that wheels

have a coffieient of drag(the ratio of the drag on a body moving through air to the product of the velocity and surface area of the body, then
a conveyor moving at unimaginable speeds could keep the plane from foving forward in space. Taking that scenario the plane would not move
untill the conveyor got to the speed of light then the plane would be able to move forward. Just a matter of what is meant by matching the
planes speed to me it meant to keep it from moving forward in space.
Your reading more into the problem than the problem will allow for. You are making an assumption that is not part of the query. If liftoff speed for a given is 100MPH, the plane will proceed to that speed irregardless of the speed of the conveyer, the only variable is tire speed, which will exponentially increase as the speed of the plane and the ground increase. Fact is the ground (conveyer) has no bearing on the holding the plane stationary, and I dare say that any bearinged wheel hub can allow for a 200mph tread runnout speed. Again, this has no bearing on the problem, as it's hypothetical and does not take such things into account.

Another way to look at it, if you had a way to affect amount of wind in addition to the moveable conveyer and you had a way to increast wind speed as the thrust of the plane increased, making the plane effectively (stand still) with relation to the conveyer, the conveyer would never move, but the plane would still take off once the airspeed increases sufficiently to create enough lift to overcome the overall weight and drag that the plane imparts.

Busted...

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It appears that you may have mis-read the original statement. A number of people seem to overlook the ability of the plane to move, although it's clearly stated in the second sentence.

From the first page, back in 2006, the original quote:

a plane is standing on a movable runway( something like a conveyor).as the plane moves the conveyor moves but in the opposite direction.the conveyor has a system that tracks the speed of the plane and matches it exactly in the opposite direction.

the question is

will the plane take off or not?



Note where it says "as the plane moves". If the plane is moving north (for example) at 50mph, the conveyor will be moving south at 50mph. The plane's wheels will be spinning at 100mph. That does not matter, because the plane is not wheel-driven. The moving conveyor will not prevent the plane from moving or from taking off once it reaches takeoff speed.

According to your premise, if the wheel drag was sufficient, when the conveyor reached a certain speed, it would begin to to slow the plane and eventually start to drag the plane backwards. However, the plane would take off long before that.

If the plane is moving north at 50mph, and the conveyor below it is moving south at 50mph, then, the plane is motionless relative to the eath and air. It takes air movement relative to the plane's wings to create lift. No motion relative to air; no workie.

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My premise is that by matching the
plane's speed it means to keep the plane from moving forward in space.
Due to the fact that wheels

have a
coffieient of drag(the
ratio of the drag on
a body moving through air
to the product of the velocity
and
surface
area
of the body, then
a conveyor moving at
unimaginable speeds could keep the plane from foving forward in space.
Taking that scenario the plane would not move
untill the conveyor got to
the speed of light then the plane would be able to move forward. Just a
matter of what is meant by matching the
planes speed to me it meant to keep it from moving
forward in space.

Yes as stated you read
something extra into the question. Obviously a normal plane needs
forward motion for flight without the forward motion a normal plane
would fall like a brick from the sky let alone be capable to take off
for flight.

Also a conveyor with unlimited speed, capable of
matching the forward motion and keeping the plane completely still and
not moving forward in space does not exist. It would still be
questionable if it is even possible if enough friction could ever be
generated through the wheels giving the conveyor unlimited potential
that a conveyor could keep the plane from moving forward. It would be
easier (and has been done) to create a plane that needs no forward
motion for flight or take off than it would be to create a conveyor with
this unlimited potential.

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