Jamescorsa97
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Registered: 19th Aug 04
Location: Middlesbrough Drives: Cliosport 182
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I can't believe this is till being debated!!!!!!
The answer was told on the first page with a good explantion on the second!!!
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Ian
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Registered: 28th Aug 99
Location: Liverpool
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quote:
Originally posted by SVM 286
If the 'ground' beneath the plane is advancing towards it at an equal speed, then the plane cannot attain speed in relation to the surrounding air to produce the lift required for take-off.
Thats actually wrong - the plan CAN attain speed in relation to the air.
The ground speed does not affect the planes ability to propel itself through air.
Jet engine pushes air. Plane moves. Plane gets lift.
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SVM 286
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quote:
Originally posted by Ian
quote:
Originally posted by SVM 286
Not thrust Paul, SPEED.
Speed is a product of force that way minus force the other way.
One is a fuck off big engine, the othre is some frictionless wheels.
While its possible to balance the two, the engine would win.
No it wouldn't.
The power of the engine/s is not a factor.
The lack of air movement past the craft is the most important point.
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Ian
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Registered: 28th Aug 99
Location: Liverpool
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I don't see how engine power is not a factor given that this is part of the prerequisite for a stationary plane on a moving belt.
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Paul_J
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Registered: 6th Jun 02
Location: London
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sigh.
SVN the engine is what makes the plane move, hence air past wings and hence lift.
^^^^^^^^^^
THIS IS NOT - I REPEAT NOT!!!!!!!!!!!! WHAT WE THINK IS HAPPENING.
THIS IS WHAT YOU THINK WE'RE TALKING ABOUT.
Imagine the conveyor belt is miles long, and the plane can accelerate down it like a normal run way. IT does not sit on one spot and suddenly lift up.
We're saying the plane can move forward.
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Mase
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Registered: 16th Sep 01
Location: Derbyshire
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but the power of the engines is possibly the most important factor, as this is what over powers the forces of the conveyor to accelerate the plane and concequently make it take off.
Mase
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Ian
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Registered: 28th Aug 99
Location: Liverpool
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quote:
Originally posted by Paul_J
We're saying the plane can move forward.
Can and would - there's very little to stop it.
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Jules S
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Registered: 24th Dec 03
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quote:
Originally posted by Jules S
Lets stop to think here for a minute.
And please people, stop to read this before posting more guff.
Lets consider what forces the conveyor can exert on the plane.
If accelerated quickly enough it will be very possible that the plane would remain stationary and the wheels would simply spin, whether thats forward or reverse.
Therefore the conveyor belt has little or no influence on the movement of the plane regardless of speed. All the energy of the conveyor belt is/can be expended in moving the planes wheels, not the plane itself.
The mass of the plane itself is therefore completely disconnected from the conveyor belt. the jet engines are therefore quite capable of moving the plane forward. All that will happen is that the wheels will be travelling at twice the speed they should be in order to take off.
^^ all my own work that....easier to explain when you dont have work to do!!!! 
Im still closest to explaining it IMO
From page 18 is it?
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Ian
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Registered: 28th Aug 99
Location: Liverpool
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I'm clear.
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Paul_J
yup
He thinks if 2 things go at each other at the same speed they will be equal, regardless of forces, masses etc
Paul.
If you ran on a conveyor belt that could match your speed you would maintain a geo stationary position, yes?
If you ran on the same conveyor belt on roller skates with wings and a jet engine on your back, you still wouldn't be able to alter your position in relation to the earth, or for that matter take off, because the conveyor would still match your speed and you would be unable to attain any gound speed in relation to the earth or the surrounding air in order to gain lift.
Please tell me you can understand that.
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Paul_J
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Registered: 6th Jun 02
Location: London
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quote:
Originally posted by SVM 286
quote:
Originally posted by Paul_J
yup
He thinks if 2 things go at each other at the same speed they will be equal, regardless of forces, masses etc
Paul.
If you ran on a conveyor belt that could match your speed you would maintain a geo stationary position, yes?
If you ran on the same conveyor belt on roller skates with wings and a jet engine on your back, you still wouldn't be able to alter your position in relation to the earth, or for that matter take off, because the conveyor would still match your speed and you would be unable to attain any gound speed in relation to the earth or the surrounding air in order to gain lift.
Please tell me you can understand that.
I think if I had a jet engine on my back and was on roller skates I could quite easily zoom along the conveyor belt, whatever speed the conveyor belt is at.
Can you understand this SVN.
If you had skates on, and held on to the rails at the side of the tread mill (thus holding yourself on the machine) - increase the speed and hold the sides. Have you fallen off? no? - are the wheels wizzing round under your feet - yup?
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Ian
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Registered: 28th Aug 99
Location: Liverpool
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Force must be equal.
Frictional loss through your contact with the belt must be equal to your jet power.
Wheel loss is small. Jet power is big.
It is likely that you would be able to overcome the belt.
If you turned your jet power down, you would stay still. If you turned your jet power up, you would overcome the belt.
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Paul_J
quote:
Originally posted by SVM 286
You HAVE to have X ammount of wind speed/pressure on the wings of an aircraft for it to take off unless it is a Harrier of a helicopter.
I think SVN thinks we're all idiots.
I can imagine him sitting there quite smug. I think I met this guy at grasshopper he seemed a decent chap. Just can't believe he can't see what is staring him in the face.
In our scenerio the plane is moving - NOT standing still like in your head.
I'm not feeling smug Paul and don't appreciate the accusation.
Quite the opposite in fact.
This is getting rather depressing in fact.
I don't think you are all idiots. Quite the opposite in fact. I wouldn't spend time on here conversing with anyone I thought was an idiot.
It's patently obvious to me that you think I am though.
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Ian
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Registered: 28th Aug 99
Location: Liverpool
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I think the stationary thing is quite possible, I just also feel that the plane would have no problem overcoming it.
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Steve
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Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
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this thread was clearly created to reach the 4 million post mark. maybe brad has a sponsorship deal with ian?
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Paul_J
In our scenerio the plane is moving - NOT standing still like in your head.
The plane can't move in relation to the ground thou Paul.
It only moves in relation to the belt.
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Ian
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Registered: 28th Aug 99
Location: Liverpool
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It moves in relation to the air, as the engines propel against the air.
The ground is not a factor. The wheels just stop the plane hitting the floor.
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Ian
quote:
Originally posted by SVM 286
If the 'ground' beneath the plane is advancing towards it at an equal speed, then the plane cannot attain speed in relation to the surrounding air to produce the lift required for take-off.
Thats actually wrong - the plan CAN attain speed in relation to the air.
The ground speed does not affect the planes ability to propel itself through air.
Jet engine pushes air. Plane moves. Plane gets lift.
If the ground is sitting still yes of course Ian. But in this case it isn't. It's moving in the opposite direction to the plane.
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Paul_J
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Registered: 6th Jun 02
Location: London
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I don't think you are an idiot, I think your stubborn. And just need to listen to what people are saying.
We all originally thought like you did, and then changed our opinions. We know How you are thinking and thus we know how it is wrong. we've tried to explain and you've just answered with things like 'Force of thrust is not important' - But the thrust is the force pushing the plane along so it's the most important one there is.
I just feel a little bit miffed, when you have half a forum who understand it, trying to explain it and then you explain to us that the plane would not take off due to it being stationary and no air under wings, like we're all idiots and not noticing that.
I think in person you could explain this alot better, and once you get one way of thinking in your head it is very hard to think openly and take on a new idea.
I just getting a bit annoyed with the fact, you keep coming back we're wrong, where we Can see and understand your point - but Understand your wrong because your generally missing some vital physics compilation.
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Paul_J
sigh.
SVN the engine is what makes the plane move, hence air past wings and hence lift.
^^^^^^^^^^
THIS IS NOT - I REPEAT NOT!!!!!!!!!!!! WHAT WE THINK IS HAPPENING.
THIS IS WHAT YOU THINK WE'RE TALKING ABOUT.
Imagine the conveyor belt is miles long, and the plane can accelerate down it like a normal run way. IT does not sit on one spot and suddenly lift up.
We're saying the plane can move forward.
If you're saying the plane can move forward then that completely negates this entire thread and Brad's question Paul.
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Paul_J
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Registered: 6th Jun 02
Location: London
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^ Sigh ^ - I suggest reading Ian, or Steve's, or Jules or whomever's posts.
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Robin
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Registered: 7th Jan 04
Location: Northants Drives: Clio 182 Cup
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OMFG *shakes head in disbelief* 
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by mase5
but the power of the engines is possibly the most important factor, as this is what over powers the forces of the conveyor to accelerate the plane and concequently make it take off.
No Mase, because we have to assume that the belt will match the planes attemts to advance because Brad stated that they both move at the same speed.
If you stood on a tread mill (regardless of it's length) on rollerskates with a fan or jet motor on your back pushing you forward in relation to the belt at the same speed, you would remain in the same location to anyone viewing you.
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Jamescorsa97
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Registered: 19th Aug 04
Location: Middlesbrough Drives: Cliosport 182
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SVM are u stringing us all along into one big joke that you don't actually understand this?
[Edited on 24-05-2006 by Jamescorsa97]
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Paul_J
I think if I had a jet engine on my back and was on roller skates I could quite easily zoom along the conveyor belt, whatever speed the conveyor belt is at.
No paul, that's what I mean. You wouldn't, because the belt would match your speed.
That's the point i'm trying to get across, and the point of the original question.
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