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A backpack helicopter is a helicopter motor and rotor and controls assembly that can be strapped to a person's back, so that he can walk about on the ground wearing it, and can use it to fly. Its harness, like a parachute harness, should have a strap between the legs, so that the pilot does not fall out of the harness during flight. Some designs may use ducted fan design to increase upward thrust. Several inventors have tried to make backpack helicopters, with mixed results.
Typically a backpack helicopter differs from a conventional helicopter in two ways. Firstly there is no tail rotor, and the main rotors are contra-rotating. Yaw is controlled by fine adjustment of a differential gear in the rotor drive transmission. When one rotor is adjusted to spin slightly faster than the other it induces yaw, or turning motion. Secondly, the rotors are fixed pitch, which assists with simplicity, however this means that in the event of engine failure autorotation is impossible. Usually a ballistic parachute would be incorporated for safety.
A Popular Science magazine in 1969 featured a backpack helicopter that used small jet engines in a tip jet configuration instead of contra-rotating rotors. This design could function in autorotation. Related are devices like a backpack helicopter which also include a seat and leg supports and are actually very small open-topped ordinary helicopters. In theory, a helicopter would be more efficient than a rocket/jet pack, possessing a greater specific impulse, and being more suited to hovering due to the smaller velocities of the propelled gases.
Pure backpacks 
- The Heliofly was a make which was designed in Germany in 1941 onwards.
- The Pentecost Hoppicopter was developed by an independent inventor and demonstrated to the military in 1945.
- Rhyme (made in Japan)
- Libelula (dragonfly) from Tecnologia Aeroespacial Mexicana (TAM) with a 2-bladed rotor driven by a small rocket motor at the end of each rotor blade. Info. (They also make a jetpack.)
- The NASA Puffin is another VTOL strap-on helicopter, which like the AeroVironment SkyTote can also transition to horizontal flight 
With a seat 
- SoloTrek XFV (Exo-skeletal Flying Vehicle).
- Martin Jetpack
- Vortech designed various models which have seats. They formerly also made a pure backpack model with two very long rotor blades driven by a little propane-powered jet motor at the end of each blade.
- The Aerospace Corporation's Springtail 
In popular culture 
Several action figures came equipped with backpack helicopters. Such an accessory was released as part of the G.I. Joe toyline for any figure to use. The Annihilator figure had a helicopter back-pack as part of its accessories. Another vertical example is the Turbo-Copter unit for the popular Action Man toy figure.
- The 1984 Commodore 64 game H.E.R.O. (Helicopter Emergency Rescue Operation) featured a protagonist who wore a helicopter backpack
- The game Super Monkey Ball Deluxe shows Dr. Bad-Boon using a backpack helicopter
- In the 2009 game Scribblenauts a backpack helicopter can be summoned using the phrase "helibackpack".
- In the 1973 Woody Allen film "Sleeper" Allen's character Miles Monroe tries to escape from the government's security police while using a largely ineffective backpack helicopter. He could not rise more than a few feet off the ground and only for several seconds, despite much arm-flapping.
- Rotor, a villain from the 2010 LEGO Hero Factory toyline, has a helicopter pack that he uses as a weapon and a flight mechanism.
- A backpack helicopter is featured in the Ratchet and Clank series.
- Karlsson-on-the-Roof from books of Astrid Lindgren has something similar to a backpack helicopter on his back.
- Inspector Gadget also had a helicopter, though not in a backpack and was deployed from the top of his hat.
- Spirou et Fantasio build a back pack helicopter in the album Spirou et les héritiers
See also 
- "Heliofly". Geocities.com. Archived from the original on 2009-10-22. Retrieved 2009-07-26.
- "Baumgartl Heliofly I helicopter - development history, photos, technical data". Avia.russian.ee. Retrieved 2009-07-26.
- NASA Puffin
- "Aircraft and Jet books and videos". Vortechonline.com. Archived from the original on 27 June 2009. Retrieved 2009-07-26.
- [dead link]
- MyFreeTemplates.com (2003-11-05). "PAV Springtail EFV". Trekaero.com. Retrieved 2009-07-26.
- Posted by Joshua (2004-02-29). "Scribblenautics: Tons of new videos and a new trailer...Part 1". Scribblenautics.blogspot.com. Retrieved 2009-07-26.