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Aircraft inventions

  1. May 27, 2007 #1
    hi all, im new to the forum as you've probably guessed. this is probably the last thread i'll ever start, and im probably about to make a tit of myself cause i dont really know anything about physics but..

    im starting to wonder why nothing seems to be available to buy, that will simply allow you to travel through the air, not too high up, not very fast. just gentle flying. ive looked up flying bikes, all I find is things similar to gyro coptors. all big structures that seem expensive..

    would it not be relatively simple to have something you grab onto, press a lever, and you're propelled forwards..? do rocket packs and backpack propellers actually exist? or are they just from cartoons?

    i was watching a documentary once with a guy travelling around a desert. He had a bike with propellers that spun when he peddalled and allowed him to hover a good few feet off the ground whilst traveling about 15mph. but ofcourse there was no emphasis on this in the programme, i rememeber thinking wow, where could i get one of those?!:bugeye:

    cars are so inconvenient and you have to stick to roads, not to mention all the laws with it. planes and helicoptors are too big and you need licenses, lots of lessons, and a lot more money.

    i just want a simple way to cross 4 about miles of cornfields between me and me girlfriend instead of having to drive the road route which is about 8 miles with my car thats falling to bits and costs too much in petrol.:uhh:

    and dont say walk.:tongue: i look forward to any responses/discussions raised
  2. jcsd
  3. May 27, 2007 #2


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    Welcome to PF, Reddy.
    It's all a matter of practicality. There is a definite amount of power required to lift and propel something. For a rotor system, that mandates a minimum size for the blades. For any system, a motor of sufficient capacity is needed. In addition, a sizeable fuel suppy needs to be part of the package.
    There have been jet and rocket packs tested for years. They are incredibly expensive and generally hard to control. I think that the peroxide rocket version has a total flight time of something like 30 seconds as determined by the fuel supply.
    Fred and a couple of others can give you lots more info.
    You might look into buying a hang-glider and building a couple of launching rigs (one at each home), but I doubt that it would work very well.
    Are you sure that it was a documentary that you were watching with the bicycle guy? That sounds a little fishy.
  4. May 27, 2007 #3
    thanks for your reply danger. the flying bike on the tv i saw was actually a pretty big structure, it was a long time ago, thinking about it harder i remember there was a sort of glider attatched to it, perhaps it mainly just floated a good distance after setting off the top of a sand hill.
  5. May 27, 2007 #4
    This is not very complicated. There is a range of micro light aircrafts available. They can be baught as kit you can build yourself or as ready built.

    Of cource it is important to choose one that is approved by the local airwothiness authorities.

    Some of these ultralights looks more like a hangglider with an engine while other looks more like an aircraft.

    For some of them you can buy engine and parts as standard part.

    Such a microlight is much more cheap than an ordinary aircraft (But it also have some more restrictions.) Operations outside ordinary airfields can be possible. (I have seen farmers flying to each other to drink coffe.)

    reddy87 -> It is just something that can be done if you got some money for it. It is cheap compared with an ordinary aircraft, but it is not for free.

  6. May 27, 2007 #5
  7. May 30, 2007 #6
    thanks langbein, i particularly like the powered paraglider :)
  8. May 31, 2007 #7
    hey, all i have gotta say over it is that it is plausible but completely with no profits.. it ll be much cheaper n easier(i mean safer, u might blow urself up n get buried in the corn field n be a scare crow thereafter, if anything goes wrong in ur aircraft) to travel 8 miles on road. ur idea, theoretically, is completely possible but practically, to build such a machine first, u need a lot of gold(or money as u know it), then if u r able to build it, it ll be very hard to control. people hav tried it n hav built them but all of em go to meuseums or personal achievement room rather than ur garage.
    n one more thing, if u hav ever seen mythbusters(on discovery's channel), they tried it in season 2, episode 19- JET PACK. they did built it n theoretically, it flew(it did took off the ground, about 10 inches i guess) but it is hell of a difficult thing to humanly control it(i mean to balance all the forces).. its all a sci fi rubbish idea to build such a thing for a daily use like jetsons(remember them? they were modern flintstones) did on cartoon network.
    also UAV(unmanned aerial vehicle) r quite common, some seniors from my college made it last year.. all u hav gotta do is that u make it a lil bigger n put urself on it(but i wont do that if i were u). on test flights, it was shakin like it was put on the piston of a ferrari engine. with all the advanced electronics, it was still far from being balanced.
    so believe me dude, i dont think u ll ever see anything of this sort in future(never i mean).
    n lastly if however it comes into existance, try n think wut the traffic rules wud be like. give it a shot. u ll fail, i bet my life on it
  9. Jun 2, 2007 #8
    Ultralights and Jet Packs has nothing in common.

    Ultralights are typically aircraft models that has been approved by airwothiness authorities to be safe enough to fly, and they are typically prebuilt as kit by approved manufactorers.

    Just an typical example as found using Google:

    At the airfield where I'm living they are flying ultralights allmost every day when it's nice wether during the summer.
  10. Jun 2, 2007 #9
  11. Jun 3, 2007 #10


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    When I belonged to the EAA (Experimental Aircraft Association), most of the aeroplanes that my friends had were homebuilt. They were all covered by the canopy of 'ultralight'. That meant Volksplanes, BD5's, Flutterbugs... you name it. Still, all were true aeroplanes. I'm not sure if hang-gliders even existed at the time, but sure as hell nobody had put a motor on one. Now that motorized hang-gliders are considered 'ultralights', I wonder what caterory the aforementioned fall into.
  12. Jun 3, 2007 #11
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