Unibus Scooters

The Unibus was a scooter designed by Harold Boultbee, built by Gloster Aircraft Co and produced from 1920 to 1922.

This machine was one of the best and most advanced designs of that era and, unlike most others, had the modern-styled enclosure and a flat floor behind the apron. The body sat on a channel-section frame with leaf-spring suspension for both 16-inch pressed steel split-rim wheels.

It had a single-cylinder, 269cc two-stroke, air-cooled engine fitted just behind the headstock, with the crankshaft on the machine axis. The magneto went in front and a clutch and two-speed gearbox behind, this then driving a shaft running back to an under-slung worm at the rear wheel. The worm wheel housing incorporated two sets of brake shoes in the rear hub.

It was advertised as 'the car on two wheels' and was marketed at 95 guineas (£95.75) - a whole year's wages for most working folk - and as such did not attract many orders. This was a shame, because the Motorcycling Magazine of 28 June 1920 said, " From whatever standpoint the Unibus is viewed, it stands as an engineers job from start to finish. The design marks a new era in the march of progress of the two wheeler." Gloster's attempt to diversify from military aircraft even looked like a Vespa, with a starting handle on the dashboard. Pressed aluminium panels hid the mechanical portions and the steel frame even incorporated a parcels compartment under the seat.

Although the Unibus was an advanced design, it proved to be too expensive for its market and was short lived.

Unibus 1920

Shaft drive on British machines is found on two extreme types - the miniature and the fully developed three-wheeler. Above is seen the worm-driven rear wheel of the Unibus.

Olympia Show 1920

Unibus. (Stand 26.)

  • 2½ h.p.; 70x70 mm. (269 c.c); single-cylinder two-stroke; drip feed lubrication; B. and B. carburetter; C. A. V. chain-driven magneto; two-speed constant mesh gear; shaft and worm, drive; Dunlop 16x2½ in. tyres. Price ninety-five, guineas.

Gloucestershire Aircraft Co., Ltd., Sunningend Works, Cheltenham.

One of the most interesting exhibits in the miniature line is the Unibus chassis, which shows distinct originality. The motive power is a 2½ h.p. two-stroke engine set across the frame, which drives through a single dry plate clutch to a two-speed gear box built car fashion across a channel steel frame. From gear box to rear wheel the transmission is by propeller-shaft, on the end of which there is an enclosed worm drive. On the inside of the worm are the two internal expanding brakes, one controlled by hand and the other by foot. The rear wheel of the machine is sprung on quarter-elliptic springs, the wheel being carried in a separate frame. The forks are also provided with leaf springs, which extend from the fork crown to the fork links, and both wheels are of the disc variety. The engine is started by means of a free-wheel hand starter mounted on the dashboard and connected to the engine by a chain. Ease of cleaning and weatherproofing are keynotes of the design.

Olympia Show, 1920

The Motor Cycle, December 2nd, 1920.

Gloster Aircraft Co

The Gloucestershire Aircraft Company was a British aircraft manufacturer.
  • The company produced a famous lineage of fighters for the Royal Air Force (RAF); the Grebe, Gladiator, Meteor and Javelin. It also produced the Hawker Hurricane and Typhoon for the parent company Hawker Siddeley. Gloster produced the first British gas turbine-powered aircraft: the E.28/39 and the first British (and only gas-turbine-powered Allied aircraft to see service in World War II) production jet fighter in the Meteor. Gloster's test runway became famous for the first flight of Sir Frank Whittle's turbojet in the E.28/39 aircraft.

    1916 Company founded.

    The Gloucestershire Aircraft Company was formed in 1917. The company acquired the aircraft business previously carried out by H. H. Martyn with a 50% share, and the Aircraft Manufacturing Co the other 50%. The company rented what was the Sunningend works of H. H. Martyn in Cheltenham, Gloucestershire. As orders for aircraft increased, other companies in the Gloucester and Cheltenham district were contracted with work. Where any flying was involved the aircraft were moved to an Air Board aircraft acceptance park at Hucclecote seven miles away by motor transport. Although Huccelcote aerodrome was used by the company it had no hangars until 1921 when it rented part of hangar from the Air Board.

    In 1926, the name of the company was abbreviated to the Gloster Aircraft Company because customers outside of the United Kingdom found the original name too difficult to pronounce.

    With the move to metal construction the Sunningend factory was no longer suitable and in 1928 the company bought the aerodrome at Hucclecote with all the hangars and office accommodation.

    In 1934 the company was taken over by Hawker though it continued to produce aircraft under its own name. In that same year the company produced the famous Gladiator biplane. The 1935 merger of Hawker Aircraft and the interests of John Davenport Siddeley (Armstrong Siddeley and Armstrong Whitworth Aircraft) saw Gloster become a part of Hawker Siddeley.

    1937 Aircraft constructors. "Gauntlet" Aircraft. "Gladiator" Aircraft.

    The Gladiator was a biplane fighter, used by the RAF and the Royal Navy's Fleet Air Arm (FAA) as the carrier-capable Sea Gladiator, as well as a number of other air forces, during World War II. The aircraft had a top speed of around 414 km/h. The Gladiator had an enclosed, single-seat cockpit, cantilever landing gear and a two-blade, fixed-pitch propeller driven by a Bristol Mercury air-cooled engine. A total of 756 airframes were built: 480 RAF, 60 FAA, 216 exported to 13 countries. Gladiators were sold to Belgium, China, Egypt, Finland, Free French, Greece, Iraq, Ireland, Latvia, Lithuania, Norway, Portugal, South Africa and Sweden.

    Although serving valiantly in the first years of the Second World War, the Gloster Gladiator was sorely outclassed by contemporary monoplane fighters such as the Messerschmitt Bf-109, and destined to be the RAF's last biplane fighter.

    Having no modern designs of its own in production, Gloster undertook manufacture for the parent company Hawker. In 1939, the company built 1,000 Hawker Hurricanes in the first 12 months of World War II and delivered its last of 2,750 Hurricanes in 1942. Production was then switched to the Hawker Typhoons for the Royal Air Force, 3,300 being built in total.

    Frank Whittle's memorial showing a full-scale model of the Gloster E28/39On 8 April 1941, the first test flight of the Gloster E.28/39 with a turbo-jet engine, invented by Sir Frank Whittle. took off from the company's airfield at Hucclecote. This formed the basis for the Gloster Meteor, the only jet to be used by the Allied Forces during World War II.

    The Meteor was the first operational Allied jet fighter aircraft of World War II. First flying with the British Royal Air Force (RAF) in 1943, the Meteor commenced operations in mid-1944, only some weeks later than the world's first operational jet, the German Messerschmitt Me 262.

    In 1945 a Meteor F Mk.4 prototype, stripped of armament, gained a World Speed Record of 606 mph with Group Captain H. Wilson at the controls. In early 1946, another F Mk.4 prototype was used to set a world air speed record of 616 mph (991 km/h) true airspeed with Group Captain "Teddy" Donaldson flying the highly modified Meteor, nicknamed "Yellow Peril." Meteors remained in service with several air forces for many years and saw action with the Royal Australian Air Force (RAAF) in the Korean War. Eventually, Gloster Meteors in fighter, trainer and night fighter versions were in operational use by 12 nations.

    During Gloster's "heyday," in 1947, S/L Janusz Zurakowski was employed as an experimental pilot. In the following years, he became one of the world's most famous experimental and aerobatics pilots. He developed a new aerobatic manoeuvre, the "Zurabatic Cartwheel", which held the audience captivated as he suspended the Gloster Meteor G-7-1 prototype he was flying, in a vertical cartwheel at the 1951 Farnborough Air Show), a manoeuvre the announcer declared to be "Impossible!" Serving for a brief period as the chief test pilot, he tested the many experimental versions of the Gloster Meteor, Javelin and E.1/44 fighters. During the Gloster years, "Zura" as he came to be known, set an international speed record: London-Copenhagen-London, 4-5 April, 1950.

    In 1952, the two seat, delta winged Gloster Javelin was developed as an all weather fighter that could fly above 50,000 feet at almost the speed of sound. This modern aircraft proved to be too heavy to take off from the short airfield in Hucclecote, and was instead fitted out to the bare minimum and given a very small fuel load. It was then flown in a short hop to RAF Moreton Valence three miles to the south, where the aircraft would be completed. It was this shortcoming of the facilities, along with the rationalisation of the British aircraft industry, that would lead to the demise of Gloster.

    In 1961, the company was merged with Armstrong Whitworth to form Whitworth Gloster Aircraft. Following another re-organisation, the firm became part of the Avro Whitworth Division of Hawker Siddeley Aviation in 1963, and the name Gloster disappeared as Hawker Siddeley rebranded its product line under its own name.

    1961 Manufacturers of the delta wing Gloster Javelin jet fighter.

    The site at Hucclecote was sold in 1964. The runway, while still visible from the air, has been partially obstructed by buildings on what is now the Gloucester Trading Estate. Many of the firms based on the estate are housed in former hangars.

Source: Graces Guide

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