The Gyrodyne RON Rotorcycle (originally designated HOG) was a tiny, single-seat helicopter designed under contract for the United States Navy in the mid-1950s. It was later redesigned for a U.S. Marine Corps requirement for a small personal helicopter that would fulfill an array of roles, including observation, liaison, small unit tactical maneuvers, and which could be dropped to downed airmen behind enemy lines to facilitate their escape.

Development

Gyrodyne purchased the assets of Bendix Helicopters in 1949, including the Model 2C coaxial helicopter which provided the technology for the XRON-1. In 1951 the Model 2C was demonstrated to the Navy with shortcomings noted in autorotation control. The XRON-1 was demonstrated under a new Navy contract NOas 55-388-c for a lightweight single man helicopter.

Design

Gyrodyne's design was an open-framework helicopter with coaxial rotors, which was evaluated with three different power plants (two reciprocating, one turbine).

The XRON-1 used a manually started 40hp two-cycle engine with a gross weight capability of 500lb. The fuselage is a simple box-beam construction. The rotor uses co-axial blades which alleviate the need for an anti-torque tail rotor. Yaw control is provided by rotor tip mounted "tip brakes" providing differential torque between the rotors. Gyrodyne patented the control on 24 October 1954 Patent No. 2,835,331. There is a small inverted V-tail for control at forward speeds. The rotors are laminated wood construction. The mast is pressure lubricated and becomes a cooling surface for oil inflight. The landing gear consists of three small wheels.

Operational history

Gyrodyne RON Rotorcycle making a water landing

The first flight was in November 1955. The two-cycle engine was prone to overheating and other engines were added to the program for testing. The Marine Corps also tested one XRON-1, and three YRON-1 prototypes.

The Marine Corps eventually concluded that both the RON, and the competing Hiller ROE Rotorcycle were too heavy and too difficult to fly and abandoned the project. The United States Navy, however, had noticed the compact size and high load-carrying capacity of the RON, and in 1960 awarded a contract to Gyrodyne to produce a radio-controlled drone version of the Rotorcycle, to be used as an Anti-Submarine Warfare platform. Using the dynamic components of the RON, this was eventually developed as the Gyrodyne QH-50.

The Rotorcycle went on to win the prize for most maneuverable helicopter at the Paris Air Show in 1961, and was selected for a 1964 trade fair in Morocco by the United States Department of Commerce.

A two-place enclosed "gyrocycle" commercial variant was proposed after initial tests.

Variants

XRON-1

prototype

YRON-1

Powered by a 55hp (41kW) 4-stroke Porsche YO-95-2 model Model GP-702/1 600cc variant with 17ft (5m) diameter rotors Powered by a 55hp (41kW) Solar YT62 turbine model with 17ft (5m) diameter rotors Powered by a 72hp (54kW) 4-stroke Porsche YO-95-6 engine variant - Rotor diameter increased to 20ft (6m), 5 units built and tested at NAS Patuxent River and Camp Pendleton Powered by a 62hp (46kW) Solar T62 gas turbine engine and 15ft (5m) diameter rotors Powered by a 72hp (54kW) 4-stroke Porsche YO-95-8 DSN-1/QH-50A engine Powered by a 125hp (93kW) Electric Engine with 50 Min endurance

Model 55

Powered by a 72 HP Porsche piston engine

Surviving aircraft

Australia

  • 4008 – XRON airworthy with Coax Helicopters of Parramatta, New South Wales
  • 4015 – XRON airworthy with Coax Helicopters of Parramatta, New South Wales

United States

Specifications

Data from Jane's All The World's Aircraft 1961–62

General characteristics

  • Crew: 1
  • Length: 11ft 6in (3.51m)
  • Empty weight: 550lb (249kg)
  • Gross weight: 832lb (377kg)
  • Max takeoff weight: 906lb (411kg)
  • Powerplant: 1 × Porsche YO-95-6 4-cylinder air-cooled horizontally-opposed piston engine, 72hp (54kW)
  • Main rotor diameter: 2 × 20ft (6.1m)
  • Main rotor area: 314sqft (29.2m2)

Performance

  • Maximum speed: 78mph (126km/h, 68kn)
  • Cruise speed: 60mph (97km/h, 52kn)
  • Range: 55mi (89km, 48nmi)
  • Ferry range: 112mi (180km, 97nmi) (overload weight, auxiliary fuel)
  • Service ceiling: 12,400ft (3,800m)
  • Rate of climb: 1,140ft/min (5.8m/s)

See also

Related development

Aircraft of comparable role, configuration, and era

Related lists

Citations

Bibliography

  • The Rotorcycle. Gyrodyne Company of America.
  • Rawlins, Eugene W. (1976). Marines and Helicopters 1946–1962. Washington, D.C.: History and Museums Division Headquarters, United States Marine Corps. p.89.
  • Simpson, Rod (1998). Airlife's Helicopters and Rotorcraft. Shrewsbury, UK: Airlife Publishing. p.220. ISBN9781853109683. OCLC.
  • Taylor, John W. R. (1961). Jane's All the World's Aircraft 1961–62. London: Sampson Low, Marston & Company, Ltd.
  • Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. p.455.

Further reading

  • Media related toGyrodyne RON Rotorcycleat Wikimedia Commons
  • Bridgman, Leonard, ed. (1958). Jane's All the World's Aircraft 1958-59. London: Jane's All the World's Aircraft Publishing Co. Ltd. p.312.

External links