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Plane on a Conveyor - IT TOOK OFF!

Discussion in 'General' started by will., 13 Dec 2007.

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Will the plane fly

  1. Yay

    89 vote(s)
    72.4%
  2. Nay

    34 vote(s)
    27.6%
  1. mvagusta

    mvagusta Did a skid that went for two weeks.

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    Well i wouldn't say any plane, but some planes, particularly those with large wing span area to weight ratios, can lift in extremely windy conditions, like a smallish cargo plane, or some small planes or ultralights, maybe even WWII bombers - no ammo, guns, bombs (empty) may lift a little.
    When the wind speed is half decent, the few that have a high thrust to weight ratio, may lift a little.

    But if they are on a conveyor belt, then there's obviously no doubt what will happen, as covered in this short 14 page thread :thumb:
     
  2. will.

    will. A motorbike of jealousy!

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    I have some words for people to digest: Flying Concrete Fish Paper

    Discuss.
     
  3. mvagusta

    mvagusta Did a skid that went for two weeks.

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    Well, if you take the speed of light into account, and the resulting heat from the bearings, it's more like "flying charcoal fish finger" but when P = O, well then, you just have frozen fish fingers, but that's just silly :lol:
     
  4. Nexxo

    Nexxo * Prefab Sprout – The King of Rock 'n' Roll

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    True, but I think this is another example of a Zeno's paradox. Zeno's equation would suggest that Achilles can never catch up with the tortoise, but common sense and experience tells us he would. The equation looks at it the wrong way so doesn't work.

    Similarly, experience and (thought) experiment tells us the plane will take off. It is impossible to make the conveyor belt match wheel speed because wheel speed is a sum of conveyor belt speed and plane forward speed. That doesn't mean the plane can't take off; it means that the equation is impossible.
     
  5. Oclocker

    Oclocker What's a Dremel?

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    No point at all - but did lack of a point ever stop such threads?
     
  6. Mord

    Mord What's a Dremel?

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    Why don't they use conveyer belts on aircraft carriers to shorten the length of the runway?
     
  7. Smilodon

    Smilodon The Antagonist

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    Because it's inefficient, expensive and not very durable. It would require a lot of energy to get that conveyor up to speed fast enough. (It can't be running when the plane is driving onto it).

    When you think about it, a conveyor would probably weigh a lot more than a plane, and will have to get up to the same speed.

    They do have a similar systems on aircraft carriers, though. It's a catapult that attaches to the front wheel of the plane. It's powered by steam from a nuclear reactor, though. (and are made for a lot smaller planes than a passenger jet)
     
  8. Nexxo

    Nexxo * Prefab Sprout – The King of Rock 'n' Roll

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    For the same reason planes can take off from conveyor belts moving in the opposite direction.

    The plane's movement is totally independent from the belt.
     
  9. Smilodon

    Smilodon The Antagonist

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    Nexxo: It would work if they applied the brakes while on the conveyor. It would probably kill both the tires and the brakes, though. I'm not sure the gear would be able to handle the load either.
     
  10. chrisb2e9

    chrisb2e9 Dont do that...

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    the launcher on a carrier has about 2,000,000 horse power. not to mention when they land they snag a cable with a hook and that stops them pretty quick.
     
  11. willyolio

    willyolio What's a Dremel?

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    because catapults work better.
     
  12. Tomm

    Tomm I also ride trials :¬)

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    Yeah, totally. It is a bit of a paradox. Though the question I was examining basically stated that equation, so based on that (rather contrived scenario), the plane can't take off.
     
  13. Jipa

    Jipa Avoiding the "I guess.." since 2004

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    That just seems to be roughly as close to the original question as "does a boat take off from a conveyor belt?".
     
  14. Tomm

    Tomm I also ride trials :¬)

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    Boats go in the water.
     
  15. mvagusta

    mvagusta Did a skid that went for two weeks.

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    The conveyor belt DOES NOT shorten the length of the required runway - if anything, when using a conveyor belt, the additional friction from the wheels might mean another few cm of runway is required, but a nice headwind can easily mean a few meteres less of runway is needed on a conveyor belt, and having a light pilot & and empty plane can mean another meter or so less runway required.... etc... Conveyors are the same as when taking off on land, just a few extra cm's from the friction from the wheels... :duh:

    Catapaults are used to directly force the heavy jets at the required take off speed, and are very different to the conveyor belt situation, as they are DIRECTLY attached to the plane via the front suspension, not via the low friction of the wheel bearings in the opposite direction!!!

    I guess this thread is at the stage where the same old discussions have been done to death 10 or 20 times, so now we are anal probing the myth from every concievable angle, using whatever we can find to shove up there :blah:
     
  16. LeMaltor

    LeMaltor >^_^

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    Just watched this on you tube, it looks dodgey, how many feet did the plane move until it was airborne? Because it just looked like its forward speed exceeded that of the conveyor, if that wasn't the case why did it move past the cones? I thought it was sposed to just take straight off? >_<
     
  17. mvagusta

    mvagusta Did a skid that went for two weeks.

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  18. Gravemind123

    Gravemind123 avatar not found

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    It would, but next there is no feasible way to perfectly make the plane go straight forward at the exact same speed the conveyor moves backwards. If you were to make it that way, it would still take off.
     
  19. Oclocker

    Oclocker What's a Dremel?

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    put a hovercraft on the belt & it flies! or does it?
     
  20. Tomm

    Tomm I also ride trials :¬)

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    It would get in the way, thus stopping the plane taking off? :p
     

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