AP 118 · No. 10 Section II · Aircraft Plate 153 / 195

Plate 153 of 195 · Cold War · Home-built single-seat autogyro

Bensen B-8M Gyro-Copter

Bensen B-8M Gyro-Copter, painted as G-BIGP, The Helicopter Museum’s Bensen B-8M Gyro-Copter, a single-seat homebuilt autogyro put together from a kit near Shrewsbury by Richard Cooper with John Whittle, first registered in October 1980 and flown from a private strip for 204 hours until its permit lapsed in 1997, then stored and given to the museum at Weston-super-Mare in 2008: the best-known of the American Igor Bensen’s kit-built gyroplanes, an open frame of square aluminium tube carrying the pilot’s seat in front of a mast, a 72 hp McCulloch flat-four two-stroke driving a pusher propeller behind it, a free-turning 20 ft two-blade teetering rotor on top and a tricycle undercarriage with a small guard wheel under the tail, shown standing on its wheels with the rotor blades fore and aft: bare aluminium frame and blades, a red vinyl seat with a blue harness and a red fuel tank beneath it, a dark blue fin and rudder carrying a cream ‘G-BIGP’ and a ringed cream ‘CG’ monogram on both sides, a Union flag on top of the tailplane and the white-painted spare propeller fitted after the original wooden one was damaged, as displayed (the mast follows G-BIGP’s photographs, which show a taller one than the published 6 ft 3 in height implies, and the engine, pre-rotator drive and control linkages are simplified).

3D model

Turn it over

A procedural model built in Blender from published dimensions, drawings and photographs, painted as G-BIGP, The Helicopter Museum’s Bensen B-8M Gyro-Copter, a single-seat homebuilt autogyro put together from a kit near Shrewsbury by Richard Cooper with John Whittle, first registered in October 1980 and flown from a private strip for 204 hours until its permit lapsed in 1997, then stored and given to the museum at Weston-super-Mare in 2008: the best-known of the American Igor Bensen’s kit-built gyroplanes, an open frame of square aluminium tube carrying the pilot’s seat in front of a mast, a 72 hp McCulloch flat-four two-stroke driving a pusher propeller behind it, a free-turning 20 ft two-blade teetering rotor on top and a tricycle undercarriage with a small guard wheel under the tail, shown standing on its wheels with the rotor blades fore and aft: bare aluminium frame and blades, a red vinyl seat with a blue harness and a red fuel tank beneath it, a dark blue fin and rudder carrying a cream ‘G-BIGP’ and a ringed cream ‘CG’ monogram on both sides, a Union flag on top of the tailplane and the white-painted spare propeller fitted after the original wooden one was damaged, as displayed (the mast follows G-BIGP’s photographs, which show a taller one than the published 6 ft 3 in height implies, and the engine, pre-rotator drive and control linkages are simplified). Drag to orbit, scroll or pinch to zoom · download .glb (256 KB)

Data plate

Specification

First flight, number built and top speed are for the whole family (Bensen, Brantly, Hiller, McCulloch, Air & Space, R22); engine, crew and dimensions are for the Bensen B-8M Gyro-Copter modelled here.

History

The B-8M Gyro-Copter

Igor Bensen was born in Rostov-on-Don in 1917, came to the United States as a student in 1937, qualified as a mechanical engineer and later set up his own company, Bensen Aircraft, in North Carolina. He wanted rotary-wing flying to be something an ordinary person could build in a garage. His answer was the gyroglider: a seat, a keel and a mast made of aluminium tube, with a free-turning two-blade rotor on top, towed into the air behind a car or a boat. He flew his first towed gyroglider in 1954, and on 6 December 1955 he flew a version with an engine and pusher propeller, the B-7M, which he called the Gyro-Copter.

The refined B-8 followed, and its powered version, the B-8M, first flew in 1957. Like the Cierva autogiros before it, the B-8M’s rotor was not driven by the engine: air flowing up through the blades as the machine moved forward kept them turning, so it could not hover, but it could fly slowly and land in a very short distance. The pilot sat in the open in front of the mast and steered with a stick that tilted the whole rotor head. Bensen sold the B-8 as plans and as kits, and over some thirty years thousands of sets of plans were sold around the world. Bensen founded the Popular Rotorcraft Association for owners and builders in 1962.

The US Air Force tested the B-8 and B-8M in 1968 as the X-25B and X-25A, to see whether a pilot ejecting over enemy territory might glide clear under a rotor rather than drift down under a parachute; the idea went no further. In Britain, Ken Wallis began with a Bensen in 1959 before developing his own WA-116, the type flown in the James Bond film You Only Live Twice as “Little Nellie”. Bensen Aircraft stopped production in 1987, but its designs are still built from plans. The gazetteer records Bensen B-7s and B-8s at six British museums, more than any other type in this light rotary flock; The Helicopter Museum at Weston-super-Mare alone keeps two B-8Ms and a B-8 Gyro-Boat alongside many of the gyroplanes that followed them.

This airframe

B-8M Gyro-Copter G-BIGP

G-BIGPThe airframe modelled

G-BIGP was built from a £1,500 kit by Richard Cooper, who lived near Shrewsbury, with help from John Whittle, under the Popular Flying Association’s number PFA G/01-1005. It was first registered in October 1980 and flown from a private site near his home, with a 72 hp McCulloch engine and the jump take-off option, a pre-rotator that spins up the rotor before the take-off run. By 1995 it had flown 204 hours. When its permit to fly ran out in 1997 it was grounded and stored, and in 2008 it was given to The Helicopter Museum, arriving at Weston-super-Mare on 10 May with a supply of spare engine parts. The original varnished wooden propeller had damaged tips, so the museum fitted the painted laminated spare that came with it. The model shows it as displayed: a bare aluminium tube frame and rotor blades, a red vinyl seat with a blue harness and a red fuel tank beneath it, a dark blue fin and rudder carrying a cream “G-BIGP” and a ringed cream “CG” monogram on both sides, a Union flag on top of the tailplane and the white spare propeller.

See it at The Helicopter Museum

Where to see one

In the gazetteer

The gazetteer records the B-8M Gyro-Copter in 13 UK collections. The airframe modelled here is marked.

Every airframe and serial All 195 plates

Profiles and models are procedural interpretations built in Blender from published dimensions, three-view drawings and photographs of each airframe. Treat the museum aircraft as the reference.