Swisscopter's Dragonfly is a small helicopter that has rocket engines on the ends of its rotors blades to propel them:

The copter makes use of tiny hydrogen-peroxide-powered rocket motors on the tips of the blades, which replaces the traditional engine-powered rotor. Large fuel tanks surrounding the pilot allow the Dragonfly to travel at up to 40 mph for 50 minutes.

via Popular Science | Company Website

hey guys....stop thinking like a regular heli...the trust created by the jets is the prim factor of this equation....the blades move in an opposit direction to the exiting energy from the jet....the body of the vehicle, thru drag, will tend to follow the directions the blades are rotating in...the speed at witch the vehicle travels depends on the friction present at the rotor bearins and the vehicle mass that is presented to the air around it..ie...if there is a lot of friction the heli will turn quicker but if the was a huge flat panel sitting flush to the direction it is rotating in then it would tend to act as an air brake and slow down the action of rotation in proportion to its size.....space travel is marvelous...time travel is quicker....zorro
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I'd have to be really convinced of the durability of those tanks in a crash before sitting amid gallons of high-test peroxide.
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this is right on it...Every action gives re-action. So the main body of the chopper will rotate in the oppsite direction of the main rotor. Don't forget that there is a fuelline-coupling from the main body to the rotorblades that gives added friction. So the tailfan is needed.
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With torque the entire force generated by the engine gets split between the rotor and the body of the helicopter.

The difference with friction as a force is two fold. First, obviously, is that it would be in the direction of the rotors, not the opposite direction. Second, we're talking an incredibly small amount of the output of the engine being transferred via friction (easily as low as .01%). Third, it takes much more energy to spin the heavier body of the helicopter than the rotors.

So it would take very, very little to cancel it out.
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This concept is not exactly new. In the 1950s a Dutch company built 11 Kolibri's (Hummingbirds):

http://en.wikipedia.org/wiki/Nederlandse_Helikopter_Industrie_(NHI)
And an American prototype:
http://en.wikipedia.org/wiki/YH-32_Hornet

All designs failed...
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