Can the Plane Take Off ?

[s2driveruk]

The plane will simply roll of the conveyor or if the plane is tethered ,as in the rolling road previously mentioned , the plane will not move and the wheels will not rotate as it is the thrust that moves the plane and not the driven wheels as the car is ,so the convevor is irelevant because the wheels are not driven

Agreed

When a plane is on the runway waiting to take off and the engines are spooled up but the brakes are on it doesn't go anywhere, just gets a bit choppy with the power of the trust! take the brakes off and away she goes. Only when its generates enough lift will it leave the runway... without airflow it ain't going anywhere

[Jamo]

Simple physics, No

A plane requires airflow to generate lift, if the conveyor is matching the planes wheels in the opposite direction then the plane remains stationary.

I saw a post about the conveyor can't negate the engines thrust.

Yes this is true, but the conveyor is negating the planes ability to generate airflow over the wings.

Think of it this way, and yes it's the same principle:

can you move foward on a treadmill?

Yes but only if you moving quicker than the treadmill is moving in the opposite direction.

Same applies here, and since the conveyor matches the planes wheels in the opposition direction, Status Quo. No Go

[S2 Ant]

Yeh but Jamo you are working on pricipals of your feet doing the propelling, in this case the wheels are on the treadmill but the engines are providing the thrust not its wheels

[Audi_CQ]

Yeh but Jamo you are working on pricipals of your feet doing the propelling, in this case the wheels are on the treadmill but the engines are providing the thrust not its wheels

Bullseye!
We have to assume that the conveyor belt is several km long. If not the plane will leave it right away when the engines are throttled up
Think of this:
1: Take a bicycle and try to ride it on the treadmill and your going nowhere even if you give it all you got if the treadmill match your speed.
2: Stay beside the treadmill and push the bike along the belt. No problem at all even if the belt is turning fast

STOP thinking on driving wheels. The wheels on a plane are just along for the ride

[Alistair C]

HA HA HA.
Jamo - OK - using your analogy, what would happen if you're wearing a jet pack on this treadmill? Whatever your feet are doing, you'll still be moving forward regardless!

The wheels could NOT keep a jet plane stationary. Just like you're feet couldn't!

if it was possible why would RAF have such long runways at a cost of millions of pounds when they can launch them from their back garden on a conveyor belt .

- you're thinking about it the wrong way - its not that the conveyor would help it take off, the point is that it wouldn't stop the plane from taking off. It'll still take off at the same airspeed, arrived at after a normal period of acceleration at full thrust!

[Ross]

SPOT ON analogy. I've been trying to figure one out... no wonder things are going **** up here at work!

I stand by my original claim... the plan will indeed take off. Make the assumption that the wheels on the plane have no mass, and that there is no friction created in the turning of the wheels, and it should become aparrent that the movement of the conveyor is not relevant to whether the plane will move forwards.

(Note, as this is real life, and friction and mass do exist, you'd find that the conveyor rapidly increased in speed to the point that the wheels failed - the more thrust, the quicker this would happen - assuming that the conveyor speed is matched to the plane's wheel speed. If the conveyor speed is related to the plane's speed in relation to the air/ground, then you'd find that the wheels were simply turning twice as fast as the airspeed indicator at takeoff, and it would take a little longer to get off the ground due to the extra energy wasted in accelerating the wheels and overcoming the associated drag. Any comments?)

[Alistair C]

Any comments?)

yup - if you're going for 'real world' no doubt the conveyor would have more troubles than the plane. The plane's wheels are just rolling. I'd suggest the gearing and rolling surfaces on this treadmill would have a seriously demanding job to perform and give up the ghost long before the plane's wheels!

[s2driveruk]

where are we getting the lift from????

[AUDI9020V]

right lets get this right a plane is on a belt and you put 100% on the engines the aircraft will come off the belt and take off,if u put a s2 on a 4x4 rolling road at speed yes it wont move but replace the engine with a rb199 rolls royce engine from a tornado then 100% power wot will happen>>>>>>it will go through the wall and guess wot move eg same as a jumbo on a belt.also lift=thrust,weight and drag
basic principles of flight.i did it at raf halton many years ago.

[Ian Simmonds]

Haven't you lot got a pub to go too?.............

[AUDI9020V]

nop dont drink and other half is out iam baby sitting

[Mark Halligan]

Haven't you lot got a pub to go too?.............

No, we've just been to the cinema since my last post though

HA HA HA.
Jamo - OK - using your analogy, what would happen if you're wearing a jet pack on this treadmill? Whatever your feet are doing, you'll still be moving forward regardless!

The wheels could NOT keep a jet plane stationary. Just like you're feet couldn't!

Well Jamo.............

[Corey]

No, we've just been to the cinema since my last post though

See anything good?

[Mark Halligan]

See anything good?

Hills have eyes,.........fooking gory

[Jon441cc]

Hills have eyes,.........fooking gory

Have you seen the original, those mutants come a cropper in the end