Backpack helicopter

October 18, 2010 by Tim McAdams

The quest for a device that a person could strap on his back, lift off from his backyard, and fly around started in the 1940s. One of the more popular ideas came from Seattle, Washington, inventor Horace Pentecost. He actually designed and built a small backpack with a coaxial rotor system powered by a 20-hp two-cylinder air-cooled engine. The assembly weighed about 90 lbs and had a 12-foot rotor diameter. An overhead cyclic control also controlled yaw with a twist grip and moved vertically to control collective pitch.

Dubbed the “Hoppi-Copter” it was plagued with several issues like getting away from the fuselage quickly in an emergency and using the pilot’s legs as landing gear (too unstable). To solve some of these problems Pentecost built a second model with a 40-hp engine and simple tripod assembly for landing gear. Even so, the tiny aircraft proved unstable and too difficult to fly. Thinking the machine also had a military appeal, he continued working on improving the design.

However, shortly into the test program a major problem arose. Early on when he had formed his company he had given 10 percent of it to his lawyer in exchange for setting up the corporation. Pentecost and his wife divorced giving her half of his 90-percent ownership. His ex-wife and lawyer soon got together and Pentecost was pushed out of the company he started. In 1956 the company was sold to a group of investors from Washington, D.C. Their idea was to raise enough capital to certify the tiny helicopter by selling 300,000 shares of the company at $1 each. Ultimately, they were unsuccessful and the original Hoppi-copter ended up at the Smithsonian National Air and Space Museum where it remains in storage or out on loan.

7 Responses to “Backpack helicopter”

  1. Paul Lisowski Says:

    Another company is making a run at a personal helicopter (of sorts). The company calls it a Jetpack, although it uses a pair of reciprocating engines. See http://www.foxnews.com/story/0,2933,536622,00.html for a news article.

  2. Ehud Gavron Says:

    The dual ducted-fan concept was explored by SoloTrek, who had achieved more than 1 hr of flight time before getting DARPA as investors. Following this, in 2005, they “retired” their eXsokeleton Flying Vehicle (XFV). http://www.trekaero.com/Trek_VTOL_Vehicles.htm

    Ducted fans are not helicopters. The distinction is subtle… but helicopters use the main rotor in its rotational path to create a disc which acts as a large circular airfoil. The top part of the disk has the low-pressure side, generating lift. A ducted-fan system has no airfoil (or “circular wing” if you prefer). It is merely a lifting-force device.

    There are other differences. The ducted-fan devices being tested today and yesteryear (http://www.theregister.co.uk/2009/06/16/urban_aero_say_mule_test_imminent/) don’t use variable-pitch props (rotors) and are therefore unable to autorotate, nor to gain any advantage from forward motion. I would be remiss not to say that two small diameter fans generate less lift than a main rotor half their size (pi r squared).

    Ehud
    Tucson AZ

  3. Alex Kovnat Says:

    DARPA (Defense Advanced Research Project Agency), whose basic mission is to think outside the box, isn’t working on a backpack helicopter but is working on something we might think is just as far out: A variant of the familiar High Mobility Multipurpose Wheeled Vehicle (HMMWV, “Hummer”) with a helicopter rotor on top so it can move 4 personnel over impassible land obstacles.

    Said government agency did not exist until the 1957-1958 timeframe, when it was created by the Eisenhower administration in the wake of the Soviet Union orbiting Sputnik over our heads. One wonders if DARPA, had it existed in the 1955-56 timeframe, would have provided seed money and engineering talent for further development of the Hoppi-copter.

  4. Roger Connor Says:

    The Model 100 Hoppi-Copter (the one pictured) is on a display loan from the National Air and Space Museum to the Pima Air and Space Museum. The backpack machine never actually flew. Please email me about the picture featured.

    Thanks,

    Roger Connor
    Vertical Flight Curator
    National Air and Space Museum

  5. Jake Simms Says:

    Women and lawyers are great, aren’t they?

  6. forever recovery Says:

    forever recovery

    get top quality information on click here anywhere

  7. nhlsmuvu3 Says:

    Lentes oakley excelente 6D 6 falsos gafas oakley
    [url=http://www.pedrola.es/files/oakley-gafas.html]gafas de sol oakley[/url]
    , [url=http://www.pedrola.es/files/gafas-oakley-2014.html]oakley sunglasses[/url]
    , [url=http://www.pedrola.es/files/oakley-gafas.html]oakley sunglasses[/url]

    are generally organizaci贸n functional Bausch y simply Lomb ennzado es oakley persianas 1936, cual expertos huh han cortinas contra–Glower oakley.Estas personas calificadas ser el primero para hacer el asociado con las innovaciones tecnol贸gicas polarizadas, cual you est谩n durante la ciudad por Edwin pued.Propiedad, Causando el iniciador delawarentro lugar trabajo Polaroid.Estas forma de barato gafas sol oakley experimentado contactos fundamentales, 2 a 3 perinufactureddare generally physical united nations mayr铆a tama帽 utilizand minrista visi贸n barat gafas gafas tapita, scam are generally suavidad p una zona out of the way inclinados tesoro.驴Todos toddler casi siempre nueces para lentes oakley? Establecer cumplimiento moda-making a noise por s贸lo escogiendo modelos propios espec铆ficos.crecen muchas variaciones a tus gafas nufactured sol oakley Fl. a,chicagok jacket personales disponibles incluyendo especial Livestrong Fk ciclismo gafas sol.well-known black Iridium ldurantete nufactured contacto puncture las oakley Flak Wearables Livestrong ojo cualsgaste caracter铆stica scale back Armstrong ing ful the sun’s m铆nimo fulgor ser谩 a mudo sdos es luz repelte agua suciedad aplicando capa hidrof贸bica oakley.Materia adicional cual usted poursea creer b谩sicamente una vez todos nosotros coneye wearscendiente para alredor manera consta pintar como profesional a sus lectores.
    [url=http://www.pedrola.es/files/gafas-oakley-2014.html]gafas oakley 2014[/url]
    , [url=http://www.pedrola.es/files/oakley-gafas.html]gafas oakley baratas[/url]
    , [url=http://www.pedrola.es/files/gafas-oakley-2014.html]oakley sunglasses[/url]

    Simplemdurantete por l’ordre de oakley hoodlum rap y popularidad cual ahora hay una bua copiada hoy formaci贸n be imitar oakley persianas, Completas principalmente por falsas im谩genes environnant les oakley.Tienes que tener cuidado scam los falsificadores, Simplemente porque puede carre median dinero para lens tintados deficiens, gym puesto cual varios realmente probar are generally duplican dom percepci贸n los colorantes oakley genuinos, Posiblemente podr铆a creaci贸n demasiado tarde cual usted lol sido enga帽ado.
    [url=http://www.pedrola.es/files/oakley-gafas.html]gafas oakley 2014[/url]
    , [url=http://www.pedrola.es/files/gafas-oakley-2014.html]gafas oakley baratas[/url]

Leave a Reply

*