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  1. Standard member sonhouse
    Fast and Curious
    10 Mar '10 03:03
    http://www.physorg.com/news187374763.html

    Uses a 200 hp engine with regular petrol. Take a look at the video.
  2. Subscriber AThousandYoung
    Do ya think?
    10 Mar '10 07:09
    AWESOME!
  3. 10 Mar '10 09:08
    I wonder what the laws are regarding actually using one. I suspect most countries simply don't have any laws.
  4. Standard member sonhouse
    Fast and Curious
    10 Mar '10 19:05 / 3 edits
    Originally posted by twhitehead
    I wonder what the laws are regarding actually using one. I suspect most countries simply don't have any laws.
    They mentioned in the US anyway, if it is under a certain weight, 260 pounds(?) or so, you don't have to have a license to fly it. Of course 20 years down the line, if and when they get truly popular, new laws would come about, that is what congress is for, to make newly minted criminality, eh.

    One thing I was wondering about, they mentioned the engine being 200 Hp, that is a lot of Hp to lift one person off the ground. I wonder what energy is being lost? Inefficiency in the blades? Could a more robust blade design get the power needed down to 100 Hp or less? There is energy clearly lost somewhere. They mentioned being able to lift a maximum of 120Kg, or 264 pounds. I imagine therefore that is the max downward thrust of the engine/blade combination. Does anyone have figures for other forms of downward thrust machines, like the Harrier for instance, what is the thrust/hp ratio? Here it is implied to be 200 hp for 264 pounds of thrust or about 1.3 pounds of thrust per horsepower. Anyone know how that compares to other machines, helicopters for instance?

    Theoretically speaking, if that engine were to be powering a lift like an elevator where you get to use pulleys and such, 1 Hp is defined as the ability to lift 555 pounds one foot in one second. So 200 Hp COULD lift 110,000 pounds at the rate of one foot per second, or 3,400 pounds at 1 G, which on the surface looks like you could get 12 or more times the lift if you were more efficient at the thrust/power ratio. In other words, it looks like if things were more like 100 % efficient, you could lift a person off the ground with 15 Hp.
  5. Subscriber AThousandYoung
    Do ya think?
    10 Mar '10 19:57
    Originally posted by sonhouse
    They mentioned in the US anyway, if it is under a certain weight, 260 pounds(?) or so, you don't have to have a license to fly it. Of course 20 years down the line, if and when they get truly popular, new laws would come about, that is what congress is for, to make newly minted criminality, eh.

    One thing I was wondering about, they mentioned the engine b ...[text shortened]... ke if things were more like 100 % efficient, you could lift a person off the ground with 15 Hp.
    If the thrust equalled the weight the flyer could not accelerate upwards. More power = more speed.
  6. Standard member Traveling Again
    I'm 1/4 Ninja
    10 Mar '10 22:34
    Very cool. I'd like to see a clip of it in action outdoors and not just in a warehouse...but very cool indeed.
  7. 11 Mar '10 03:01
    http://en.wikipedia.org/wiki/Jet_pack#Yves_Rossy.27s_jet_wingpack

    Yves Rossy's jet wingpack
    Rossy's wing showing the four purple and silver jet-engines mounted close to the centre

    Swiss ex-military and commercial pilot Yves Rossy developed and built a winged pack with rigid aeroplane-type carbon-fiber wings spanning about 8 feet (2.4 m) and four small kerosene-burning jet engines underneath; these engines are large versions of a type designed for model aeroplanes.[7] He wears a heat-resistant suit similar to that of a firefighter or racing driver to protect him from the hot jet exhaust.[8][9] Similarly, the engines are modified with the addition of a carbon fibre heat shield extending the jet nozzle around the exhaust tail, to further protect the wearer.

    Rossy claims to be "the first person to gain altitude and maintain a stable horizontal flight thanks to aerodynamic carbon foldable wings," which are folded by hinges at the midpoint of each wing. After being lifted to altitude by a plane, he ignites the engines just before he exits the plane with the wings folded. The wings unfold while in free-fall, and he is then able to fly horizontally for several minutes, landing using a parachute.[10] He achieves true controlled flight using his body and a hand throttle to maneuver.

    The system is said by Rossy to be highly responsive and reactive in flight, to the point where he needs to closely control his head, arm and leg movements in order not to enter an uncontrolled spin. The engines on the wing require the achievement of a precise common alignment during set-up, in order to also prevent instability. An electronic starter system ensures all four engines ignite simultaneously. In the event of a spin, the wing unit can be detached from the pilot, and both pilot and wing unit descend to Earth on separated parachutes.

    Rossy's jet pack was exhibited on 18 April 2008 at the opening day of the 35th Exhibition of Inventions at Geneva.[11] Rossy and his sponsors spent over $190,000 to build the device.[12]
    [edit] Flights

    His first successful trial was on 24 June 2004 near Geneva, Switzerland. Rossy has made more than 30 powered flights since. In November 2006 he flew with a later version of his jet pack.[citation needed]

    On May 14, 2008 he made a successful 6-minute flight from the town of Bex near Lake Geneva. He exited a Pilatus Porter at 7,500 feet with his jet pack. It was the first public demonstration before the world's press. He made effortless loops from one side of the Rhone valley to the other and rose 2,600 feet.

    It has been claimed that the military has been impressed and asked for prototypes for the powered wings, and that Rossy kindly refused the request and stated it is only for aviation enthusiasm purposes.[13][14][15]

    On 26 September 2008, Yves successfully flew across the English Channel from Calais, France to Dover, England in 9 minutes, 7 seconds[16][17]. His speed reached 186 mph during the crossing[18], and was at 125 mph when he deployed the parachute[19].
  8. Standard member joneschr
    Some guy
    11 Mar '10 05:09 / 1 edit
    30 minute flying time, 30 miles max range, 5 gallon tank.

    At 6 miles per gallon and max range of 30 miles, it doesn't seem all that practical.

    But it's a start I guess.
  9. Subscriber AThousandYoung
    Do ya think?
    11 Mar '10 05:21
    Originally posted by joneschr
    30 minute flying time, 30 miles max range, 5 gallon tank.

    At 6 miles per gallon and max range of 30 miles, it doesn't seem all that practical.

    But it's a start I guess.
    You can hop from rooftop to rooftop. Do you know of another way to do that?
  10. 11 Mar '10 05:31
    Originally posted by sonhouse
    They mentioned in the US anyway, if it is under a certain weight, 260 pounds(?) or so, you don't have to have a license to fly it.
    I was not so concerned about a licence, but rather issues like where you may be allowed to use it.
    For example, how low over somebodies property would you be allowed to fly? Could I land it anywhere, or must I stick to designated landing zones? Must I get permission to fly above a certain height (in the airspace of aircraft).


    Theoretically speaking, if that engine were to be powering a lift like an elevator where you get to use pulleys and such, 1 Hp is defined as the ability to lift 555 pounds one foot in one second.
    I rather suspect that the lift example cant be used as a lift is using a stationary mount for leverage. The jet pack must accelerate its own mass of air downwards at 1G just to stay still (I think), so any other movement would be in addition to that. A better comparison would be a rocket.
  11. Standard member joneschr
    Some guy
    11 Mar '10 23:27
    Originally posted by AThousandYoung
    You can hop from rooftop to rooftop. Do you know of another way to do that?
    No, though I've never actually had much reason to try.

    Now that you mention it though, this could really help me fix that leaking gutter I've been neglecting..
  12. 12 Mar '10 04:59
    Originally posted by AThousandYoung
    You can hop from rooftop to rooftop. Do you know of another way to do that?
    Landing on someone else's roof, would not only be risky in many cases (not all roofs can support the weight of your landing, and may be quite steep and slippery any way), but it would probably also count as trespassing and therefore be liable to prosecution.
  13. Subscriber AThousandYoung
    Do ya think?
    12 Mar '10 05:00
    Originally posted by twhitehead
    Landing on someone else's roof, would not only be risky in many cases (not all roofs can support the weight of your landing, and may be quite steep and slippery any way), but it would probably also count as trespassing and therefore be liable to prosecution.
    Jetpack infantry...
  14. 12 Mar '10 10:13
    My initial thought was that it would be useful for rescue operations but its lack of carrying capacity means I cant really think of many situations where it would be much use. For example you could not get an injured person off an inaccessible site (mountain / burning building) , you could not pour water on a fire, you probably couldn't even rescue a kitty from a tree.
    I guess you might be able to get a doctor to an inaccessible site, but thats about it.
  15. Subscriber AThousandYoung
    Do ya think?
    13 Mar '10 19:22
    Originally posted by zeeblebot
    http://en.wikipedia.org/wiki/Jet_pack#Yves_Rossy.27s_jet_wingpack

    Yves Rossy's jet wingpack
    Rossy's wing showing the four purple and silver jet-engines mounted close to the centre

    Swiss ex-military and commercial pilot Yves Rossy developed and built a winged pack with rigid aeroplane-type carbon-fiber wings spanning about 8 feet (2.4 m) and four sma ...[text shortened]... ed 186 mph during the crossing[18], and was at 125 mph when he deployed the parachute[19].
    He has to be towed into the air by a plane and cannot hover. That's more of a jet assisted glider pack than a jetpack.