mattk
Member
Registered: 27th Feb 06
Location: St. Helens
User status: Offline
|
so the plane is still allowed to accelerate on the treadmill?
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
yeah pretty much as normal
|
mattk
Member
Registered: 27th Feb 06
Location: St. Helens
User status: Offline
|
 I didnt know that, well yeah it would take off then 
|
Carl
Member
Registered: 9th May 04
Location: Jimmy Bennett's la la land.
User status: Offline
|
what if the conveyer belt is at a gradient. 
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
then you have the extra force of gravity which would make a difference, not to mention the angle of the wings would be changed altering the lift effect
[Edited on 02-02-2008 by Steve]
|
ainsley_brader
Member
Registered: 24th Mar 02
Location: Tattershall, Lincolnshire
User status: Offline
|
quote:
Originally posted by Steve
quote:
Originally posted by Robin
The only problem is, you could still prevent the plane from taking off if the conveyor belt was going fast enough.
Having the conveyor matching the plane's take off speed isn't going to stop it, as the friction in the bearings isn't high enough to slow the plane down to that point.
So it will, and won't, at the same time.
its would have to be going millions of times faster than the planes speed
the original question is If a conveyour belt was travelling in the opposite direction and it matched the planes speed would it take off
the answer is 100% yes
Cant be bothered reading 3 pages but as I see it if the conveyors speed and the aircraft speed are equal then we should see the plane taking off vertically and not moving along the runway!
In which case these experiments were completely pointless and the plane would not take off as there would be no air movement to generate any lift!
|
ainsley_brader
Member
Registered: 24th Mar 02
Location: Tattershall, Lincolnshire
User status: Offline
|
quote:
Originally posted by Steve
yeah pretty much as normal
so your matching the conveyer to normal take off wheel speed not aircraft speed?
Thats like putting a veyron on a conveyor at 100mph conveyor and veyron speed and then saying if you accelerate to 200mph will it drive off the end of course it will!
[Edited on 02-02-2008 by ainsley_brader]
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
no its not, the force to move the veyron forwards is through the wheels and that is counteracted directly on a conveyor belt, however the force to move a plane forward is from thrust against the air, the conveyor belt has no effect on the thrust or the air, the wheels on a plane are freewheeling so offer hardly any counteracting force to stop the plane moving forwards
[Edited on 02-02-2008 by Steve]
|
ainsley_brader
Member
Registered: 24th Mar 02
Location: Tattershall, Lincolnshire
User status: Offline
|
doesnt matter where the propulsion comes from you are either matching speeds or not.
If the speed that either the car or the plane was moving forward was the same as the speed of the belt. ie the vehicle wasnt moving forward then it would not lift!
(just correcting grammar)
[Edited on 02-02-2008 by ainsley_brader]
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
no, the question is if the speed of the conveyor belt rotates in the ooposite direction the same speed the plane is going, will the plane take off
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
you'l realise you're so hopelessy wrong one day and you'l laugh about how simple it is and how you were wrong
|
Cosmo
Member
Registered: 29th Mar 01
Location: Im the real one!
User status: Offline
|
why are people even arguing this 
It wont take off 
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
be quiet cosmo
|
Cosmo
Member
Registered: 29th Mar 01
Location: Im the real one!
User status: Offline
|
quote:
Originally posted by Steve
be quiet cosmo
You know the truth, you are just trying to cause an arguement by saying it will take off.
|
ainsley_brader
Member
Registered: 24th Mar 02
Location: Tattershall, Lincolnshire
User status: Offline
|
quote:
Originally posted by Steve
no, the question is if the speed of the conveyor belt rotates in the ooposite direction the same speed the plane is going, will the plane take off
Steve you are such an idiot read what you just put!
This bit
conveyor belt rotates in the ooposite direction the same speed the plane is going
same speed, same forward momentum. The question is concerned with vertical lift any plane travelling forwards will lift off we know that.
|
Cosmo
Member
Registered: 29th Mar 01
Location: Im the real one!
User status: Offline
|
Although I think people are missing the main thing you should be asking when confronted with this question....are their sankes on the plane?
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
quote:
Originally posted by ainsley_brader
quote:
Originally posted by Steve
no, the question is if the speed of the conveyor belt rotates in the ooposite direction the same speed the plane is going, will the plane take off
Steve you are such an idiot read what you just put!
This bit
conveyor belt rotates in the ooposite direction the same speed the plane is going
same speed, same forward momentum. The question is concerned with vertical lift any plane travelling forwards will lift off we know that.
lol I can't believe you're calling me an idiot, you should take a look at you're argument, IF you ever get it, you will feel the biggest idiot
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
are people really so dumb as to think a car gains momentum using the same principle as a plane 
|
mattk
Member
Registered: 27th Feb 06
Location: St. Helens
User status: Offline
|
I didnt know the plane was allowed to accelerate ( by the prop I know )
|
ainsley_brader
Member
Registered: 24th Mar 02
Location: Tattershall, Lincolnshire
User status: Offline
|
how the momentum is achieved isnt the issue is it?
I thought we were matching the the momentum?
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
il try and break it down.
you have two scenarios, a car on a belt and a plane on a belt. Lets deal with the car first.
The forward momentum on a car is from the engine transferring force to turn the road wheels, sit a car on a conveyor belt and the wheels will just be counteracted by the turning of the conveyor belt hence it will go nowhere.
Now the plane, the force is not applied through the wheels on a plane, they are freewheeling like rollerskates.
The engines produce thrust which pushes against the air hence pushing the aircraft forwards.
Now place a belt rotating under these wheels and apply a little thrust to keep the plane, what is happening? the wheels are spinning underneath the engines are applying a small amount of thrust and the plane is sat there. Increase the thrust and the plane will move forwards. The conveyor belt will speed up to match however the wheels will just spin faster under the plane. the plane will still go forward and produce lift almost as normal.
Think about what would happen landing a plane on a runway spinning towards you, the plane wouldnt just stop dead, it would still roll forwards with the wheels spinning underneath
|
ainsley_brader
Member
Registered: 24th Mar 02
Location: Tattershall, Lincolnshire
User status: Offline
|
I understand your argument steve but you are contradicting yourself?
Answer this one.
We have a plane 20ft long and a conveyer 25ft long. A sensor on the last 2 foot increases the speed of the conveyer to keep the plane within the centre 20ft of the conveyer thus matching the speed of the plane.
The planes engines reach full power does the plane take off?
|
Steve
Premium Member
Registered: 30th Mar 02
Location: Worcestershire Drives: Defender
User status: Offline
|
thats not the question, the conveyor belt would have to be spinning many many times faster then the plane is actually moving at to offer enough resistance through the wheels.
The question is "If a plane tries to take off on a conveyor belt spinning the other way, and the conveyor belt spins at the same speed the plane is moving, will it take off"
so for instance when the plane is moving forwards at 40mph the belt is spinning the other way at 40mph.
|
ainsley_brader
Member
Registered: 24th Mar 02
Location: Tattershall, Lincolnshire
User status: Offline
|
yes the plane moving at 40mph not the planes wheels!
|
Cosmo
Member
Registered: 29th Mar 01
Location: Im the real one!
User status: Offline
|
tbh it makes no difference what speed the converyor belt is running at, it could be going 10x the speed of the plane but because the wheels bascially 'free wheel' under the plane and arent driven the engines would still push the plane forwards.
|
