The Bensen B-8 is a small, single-seat

autogyro An autogyro (from Greek and , "self-turning"), also known as a ''gyroplane'', is a type of rotorcraft that uses an unpowered rotor in free autorotation to develop lift. Forward thrust is provided independently, by an engine-driven propeller. Whi ...

developed in the United States in the 1950s. Although the original manufacturer stopped production in 1987, plans for homebuilders are still available as of 2019. Its design was a refinement of the

Bensen B-7 The Bensen B-7 was a small rotor kite developed by Igor Bensen in the United States in the 1950s and marketed for home building. It was a refined to be a slightly larger version of the B-6, replacing the skids with a tricycle undercarriage, and ...

, and like that aircraft, the B-8 was initially built as an unpowered

rotor-kite A rotor kite or gyrokite is an unpowered, rotary-wing aircraft. Like an autogyro or helicopter, it relies on lift created by one or more sets of rotors in order to fly. Unlike a helicopter, gyrokites and rotor kites do not have an engine poweri ...

. It first flew in this form in 1955, and on 6 December a powered version, designated B-8M (M for motorised) first flew. The design proved to be extremely popular and long-lasting, with thousands of sets of plans sold over the next thirty years.

Design and development

The B-8's design is extremely minimalist, with not much more to the aircraft than a pilot's seat, a single tailfin, a rotor, and (in powered versions) the powerplant. In May 1968 a B-8 and B-8M were studied by the

USAF The United States Air Force (USAF) is the Aerial warfare, air military branch, service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part ...

under the Discretionary Descent Vehicle (DDV) program as the X-25B and X-25A respectively. In this scheme, it was proposed to integrate combat aircraft

ejection seat In aircraft, an ejection seat or ejector seat is a system designed to rescue the pilot or other crew of an aircraft (usually military) in an emergency. In most designs, the seat is propelled out of the aircraft by an explosive charge or rock ...

s with a small autogyro or rotor kite to allow downed pilots more control over their post-ejection landing spot. The X-25A and X-25B were used to evaluate the piloting and training requirements of the autogyros. No full-scale operational tests were ever performed. The U.S. Air Force stopped funding the DDV program with the end of the

Vietnam War The Vietnam War (also known by other names) was a conflict in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. It was the second of the Indochina Wars and was officially fought between North Vietnam a ...

.Jenkins et al
AMERICAN X-VEHICLES, X-25
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NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...

'', June 2003. Accessed: 18 February 2012. One B-8M, named ''Spirit of Kitty Hawk'' (registration ''N2588B'') was used to make a special commemorative flight exactly duplicating the first flight of the Wright brothers' original Flyer on the sixtieth anniversary of the occasion. This same aircraft was flown by Igor Bensen himself between May 1967 and June 1968 to set twelve world and US speed, distance, and altitude records for autogyros, the largest number of such records to be held by any non-military rotorcraft.

Variants

* B-8 Gyro-Glider - unpowered rotor-kite intended to be towed behind a car * B-8B Hydro-Boat - B-8 with a full boat hull intended to be towed behind another boat * B-8M Gyro-Copter - standard motorised version, main production type. Usually powered by a McCulloch 4318 engine ** B-8MH Hover-Gyro - twin, coaxial rotor design with powered lower rotor and autorotating upper rotor, giving it the capability of hovering. Upper rotor and drive propeller powered by separate engines ** B-8MJ Gyro-Copter - B-8M modified for "jump" take off by a small second engine providing power to rotor head with anti-torque provided by rudder correction under power. ** B-8MW Hydro Copter - float-equipped B-8M ** X-25A - B-8M evaluated by USAF. Single example (serial ''68-10770'') first flown 5 June 1968 and preserved at the

National Museum of the United States Air Force The National Museum of the United States Air Force (formerly the United States Air Force Museum) is the official museum of the United States Air Force located at Wright-Patterson Air Force Base, northeast of Dayton, Ohio. The NMUSAF is the ...

Wright-Patterson Air Force Base Wright-Patterson Air Force Base (WPAFB) is a United States Air Force base and census-designated place just east of Dayton, Ohio, in Greene and Montgomery counties. It includes both Wright and Patterson Fields, which were originally Wilbur Wr ...

* B-8 Super Bug - similar to B-8M but with extra engine to spin up rotor before take-off ** B-8HD Super Gyro-Copter - development of Super Bug first flown in 1979 with hydraulic drive to pre-rotate rotor rather than separate engine * B-8V - B-8 powered by a

Volkswagen air-cooled engine The Volkswagen air-cooled engine is an air-cooled, gasoline-fuelled, boxer engine with four horizontally opposed cast-iron cylinders, cast aluminum alloy cylinder heads and pistons, magnesium-alloy crankcase, and forged steel crankshaft and ...

* B-8W Hydro-Glider - float-equipped B-8 intended to be towed behind a boat * X-25B - B-8 evaluated by USAF. Single example (serial ''68-10771'') first flown 23 January 1968 and preserved at the AFFTC Museum at Edwards Air Force Base. * Rotorcraft Minicopter Mk 1 - South African variant with pre-rotator and cockpit fairing. * Aeroflyte DGH-1 - license-built model from Aeroflyte.

Aircraft on display

US Southwest Soaring Museum The US Southwest Soaring Museum is an aviation museum, located at 918 E US Route 66, in Moriarty, New Mexico, United States that focuses on the history of gliding in the western United States. The museum is an affiliate member of the Soaring Socie ...

New England Air Museum The New England Air Museum (NEAM) is an American aerospace museum located adjacent to Bradley International Airport in Windsor Locks, Connecticut. The museum consists of three display hangars with additional storage and restoration hangars. Its co ...

North Carolina Museum of History The North Carolina Museum of History is a history museum located in downtown Raleigh, North Carolina. It is an affiliate through the Smithsonian Affiliations program. The museum is a part of the Division of State History Museums, Office of Archives ...

Lewis, Rebecca, (2003
Flight of the Imagination

, Office of Archives and History, N.C. Department of Cultural Resources, retrieved 4 September 2013