# The Naked Scientists Forum

### Author Topic: Can an aeroplane on a conveyor belt get airborne?  (Read 13975 times)

#### yor_on

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #50 on: 03/04/2011 07:11:55 »
Sorry, I was writing there :)
Take a look and see what you think.

• Neilep Level Member
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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #51 on: 03/04/2011 07:18:19 »
Take a cyclist sitting on his bike, take yourself running on a treadmill.
Exactly how do you see that differing from using a propeller to get that forward moving force?
As long as you're still on that treadmill?

The propeller does not depend on ground friction to move. The runner and the cyclist do.

#### Geezer

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #52 on: 03/04/2011 07:33:08 »
Take a cyclist sitting on his bike, take yourself running on a treadmill.
Exactly how do you see that differing from using a propeller to get that forward moving force?
As long as you're still on that treadmill?

The propeller does not depend on ground friction to move. The runner and the cyclist do.

That would seem to sum it up!

Yoron,

When a plane is taking off, the engines have to produce a great enough force to overcome three forces. The three forces are the result of inertia, wind resistance and rolling resistance (the wheels).

Rolling resistance is insignificant compared to wind resistance and inertia. The only thing the stupid conveyor belt could possibly affect is rolling resistance, but even if it did, the outcome would be completely insignificant.

And don't even think about trying to introduce yet another wavy arm theory into the discussion. It simply will not stand.

#### yor_on

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #53 on: 03/04/2011 07:34:35 »
They use ground friction too, don't they? Even if powered by the propeller. Assume that it weights ten ton, all that weight (more or, as it may be later, less:) will be transferred to the wheels, as long as it's not airborn. That means that they will put pressure on that treadmill, and that the aircrafts inertia will transfer through them. What the aircraft moves by before a liftoff are those wheels.

#### Geezer

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #54 on: 03/04/2011 07:36:40 »
Bollocks! Planes do not rely on ground friction. You are simply havering.

• Neilep Level Member
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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #55 on: 03/04/2011 07:39:40 »
They use ground friction too, don't they?

No. Air movement.

The friction slows them down slightly yes, but that is not where their acceleration force comes from.

#### yor_on

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #56 on: 03/04/2011 07:42:39 »
Awh sh*
I hate this :)

Okay, as soon the inertia is overcome it won't matter.
But you just destroyed a perfectly immortal thread here.

:)

• Neilep Level Member
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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #57 on: 03/04/2011 07:43:26 »
The difference between one plane trying to take off on a normal runway and another trying to take off on a conveyor belt will be as insignificant as one ball rolling down a rising escalator and another ball rolling down an escalator that is turned off.

One example gets acceleration from gravity, the other from jet engines.

#### yor_on

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #58 on: 03/04/2011 07:44:10 »
The thing is whereas the car pushes against the ground the aircraft pushes against the air.
Ah well :)

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #59 on: 03/04/2011 07:46:23 »
We got there in the end :)

#### yor_on

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #60 on: 03/04/2011 07:49:43 »
But it will need to have a he* of a sturdy wheel set.
Smoking hot :)
=

Da* wonder why I didn't see that from the beginning?
I differed between a rocket and the jet, but my problem was that I thought of the rocket as only acting on itself, which it would do, in space. But thought of the aircraft as acting on the wheels

Awh sh*^2

We'll keep this a secret, okay :)
==

I really need a new keyboard here :)
« Last Edit: 03/04/2011 08:00:11 by yor_on »

#### Geezer

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #61 on: 03/04/2011 07:57:47 »
But it will need to have a he* of a sturdy wheel set.
Smoking hot :)

That's not a problem.

Don't feel bad. Engineers solve real problems. Scientists solve imaginary problems.

#### yor_on

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##### Can an aeroplane on a conveyor belt get airborne?
« Reply #62 on: 03/04/2011 07:59:01 »
Ah Geezer :)

Thnks?

#### The Naked Scientists Forum

##### Can an aeroplane on a conveyor belt get airborne?
« Reply #62 on: 03/04/2011 07:59:01 »