MythBusters experiment proposal - (hopefully a joint effort for forum members)

Discussion in 'Aircraft & Aviation' started by Hans Christian, Apr 23, 2007.

  1. Hans Christian

    Hans Christian Active Member

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    Guys, remember my thread about the AS paper aircraft lab?

    I mentioned there that I conducted some measurements during my catapult launches and recorded some rediculous speeds (ave. 100 kph) and accelerations (about 254 m/s(sq) )

    well, I punched these numebrs again in my calculator, and I found out that (if my readings are correct), if that acceleration rating is sustained for just a second, the glider(s) would have reached speeds in excess of 500 mph, and if the acceleration extends another 1 second (that makes 2), it would have reached well over 1,000 mph, well over Mach 1...

    I am skeptical about my calculations (and the data I recorded), but if there is a sense of realism in this scenario, then I'm proposing a (lets say) "myth"





    - Can a cat-launched cardboard glider go supersonic?





    well, the biggest hurdle here is where the hell someone can find a pretty powerful catapult to pull this one off, or how to sustain 254 m/s(sq) acceleration for at least 1.5 seconds...

    and if the launcher can indeed fling these things to Mach speeds, would they survive?

    I need help with this one guys, I am interested to pass this to the guys at MythBusters for them to have a look, of course, they are free to explore other methods and/or equippment to use (i.e., they may use steam instead of rubber bands etc.)

    well, I'm planning to improve my "usual" catapult (a long, strong slab of wood with legs attached and anchored to the ground, and using a long chain of rubber bands, with 3-4 strands per ring) that I used to record the numbers I've mentioned, by using leverage (pulley assisted) to multiply the force generated by the rubber bands to fling the plane to flight...

    Hopefully someone here could look at this topic and chew on this scientifically to see if it can be done...

    Thanks everyone! :-D
  2. Hans Christian

    Hans Christian Active Member

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    Guys, remember my thread about the AS paper aircraft lab?

    I mentioned there that I conducted some measurements during my catapult launches and recorded some rediculous speeds (ave. 100 kph) and accelerations (about 254 m/s(sq) )

    well, I punched these numebrs again in my calculator, and I found out that (if my readings are correct), if that acceleration rating is sustained for just a second, the glider(s) would have reached speeds in excess of 500 mph, and if the acceleration extends another 1 second (that makes 2), it would have reached well over 1,000 mph, well over Mach 1...

    I am skeptical about my calculations (and the data I recorded), but if there is a sense of realism in this scenario, then I'm proposing a (lets say) "myth"





    - Can a cat-launched cardboard glider go supersonic?





    well, the biggest hurdle here is where the hell someone can find a pretty powerful catapult to pull this one off, or how to sustain 254 m/s(sq) acceleration for at least 1.5 seconds...

    and if the launcher can indeed fling these things to Mach speeds, would they survive?

    I need help with this one guys, I am interested to pass this to the guys at MythBusters for them to have a look, of course, they are free to explore other methods and/or equippment to use (i.e., they may use steam instead of rubber bands etc.)

    well, I'm planning to improve my "usual" catapult (a long, strong slab of wood with legs attached and anchored to the ground, and using a long chain of rubber bands, with 3-4 strands per ring) that I used to record the numbers I've mentioned, by using leverage (pulley assisted) to multiply the force generated by the rubber bands to fling the plane to flight...

    Hopefully someone here could look at this topic and chew on this scientifically to see if it can be done...

    Thanks everyone! :-D
  3. SteveM

    SteveM Member

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    Your calculations are assuming a vacuum. Include some atmospheric drag calculations and you'll get VERY different numbers. I think that trying to push a paper model supersonic will shred it into confetti.
  4. SteveM

    SteveM Member

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    Your calculations are assuming a vacuum. Include some atmospheric drag calculations and you'll get VERY different numbers. I think that trying to push a paper model supersonic will shred it into confetti.
  5. goney3

    goney3 Member

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    MmmMmmm!... scientific confetti :D Sounds like something fun!
  6. goney3

    goney3 Member

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    MmmMmmm!... scientific confetti :D Sounds like something fun!
  7. wunwinglow

    wunwinglow Active Member

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    I wish my arrows would go supersonic; I might hit a few more golds then...

    Tim
  8. wunwinglow

    wunwinglow Active Member

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    I wish my arrows would go supersonic; I might hit a few more golds then...

    Tim
  9. Stev0

    Stev0 Active Member

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    DAMN YOU PHYSICS!!!

    Yes I think we have forgotten drag and perhaps environmental conditions.
  10. Stev0

    Stev0 Active Member

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    DAMN YOU PHYSICS!!!

    Yes I think we have forgotten drag and perhaps environmental conditions.
  11. Kaz

    Kaz Member

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    With no thrust, and dropping it straght down, won't it reach (a paper 'planes) terminal velocity?
    Peregrine Falcons hit about 200 mph.

    In our local book store we have a paper plane launcher, it comprises of a set of rubber wheels set horizontally on a launch pad, these are powered by a motor and the fuselage is coaxed in between them and its then shot out

    like this one
    http://www.amazon.co.uk/Great-Gizmos-Paper-Plane-Launcher/dp/B000EOQXBM
  12. Kaz

    Kaz Member

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    With no thrust, and dropping it straght down, won't it reach (a paper 'planes) terminal velocity?
    Peregrine Falcons hit about 200 mph.

    In our local book store we have a paper plane launcher, it comprises of a set of rubber wheels set horizontally on a launch pad, these are powered by a motor and the fuselage is coaxed in between them and its then shot out

    like this one
    http://www.amazon.co.uk/Great-Gizmos-Paper-Plane-Launcher/dp/B000EOQXBM
  13. paper warrior

    paper warrior Member

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    What if you strap a rocket to it? I have a paper airplane that could achive this, with a few mods. (re-inforcing the wings)
  14. paper warrior

    paper warrior Member

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    What if you strap a rocket to it? I have a paper airplane that could achive this, with a few mods. (re-inforcing the wings)
  15. Texman

    Texman Guest

    Yes indeed. You have four forces acting on the airframe. Lift, thrust, drag, and weight. Each must be considered on its own, and in conjunction
    with each other and the density of the air at various altitudes, which changes with temperature and humidity, etc. It is by no means and exact science.
  16. Texman

    Texman Guest

    Yes indeed. You have four forces acting on the airframe. Lift, thrust, drag, and weight. Each must be considered on its own, and in conjunction
    with each other and the density of the air at various altitudes, which changes with temperature and humidity, etc. It is by no means and exact science.
  17. Rick Thomson

    Rick Thomson Member

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    Of course if you have enough thrust the other three don't count, as the Phantom and 104 proved...
  18. Rick Thomson

    Rick Thomson Member

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    Of course if you have enough thrust the other three don't count, as the Phantom and 104 proved...
  19. MOS95B

    MOS95B Member

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    Like my dad used to say about his wire-controlled airplanes "Put a big enough engine on anything and it can fly"
  20. MOS95B

    MOS95B Member

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    Like my dad used to say about his wire-controlled airplanes "Put a big enough engine on anything and it can fly"