Bristol 138a

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules


2nd Lieutenant
Jun 23, 2006
London Ontario Canada
Immanyarok: Bristol 138 and Facebook.
PIC 1 - Look and Learn Mag 1976-01-03 - ART BY WILF HARDY.
PIC 2 - Popular Mechanics Mag 1937-01 - ART BY G H DAVIS.
The Bristol Type 138 High Altitude Monoplane was a British high-altitude research aircraft developed and produced by the Bristol Aeroplane Company during the 1930's. It holds the distinction of setting nine separate altitude world records, the ultimate of these occurring on 30 June 1937, during a 2¼-hour flight flown by Flight Lieutenant M.J. Adam, in which he achieved a record altitude, which was later homologated by the Fédération Aéronautique Internationale as having attained a maximum altitude of 53,937 ft (16,440 m).
As flown, the Type 138 was a single-engine, low-wing monoplane with a fixed, tail wheel undercarriage. From the outset it was designed as a dedicated research aircraft capable of reaching high altitudes; aeronautical engineer Frank Barnwell had first proposed the design to the British Air Ministry during November 1933. The revised design was produced in response to the issuing of Specification 2/34 by the Air Ministry during June 1934. The specification, which called for a pair of prototypes, sought an aircraft that would be capable of achieving the unheard-of altitude of 50,000 feet; it had been issued in response to public pressure in favour of government sponsoring of such record attempts.
In addition to Bristol's own work on the Type 138, the Royal Aircraft Establishment (RAE) and National Physical Laboratory also made valuable contributions to the development effort on designing the type. On 11 May 1936, the Type 138A performed its maiden flight, piloted by Cyril Uwins. On 28 September 1936, Squadron Leader F.R.D. Swain set a new world record altitude record, having climbed to an indicated altitude of 51,000 ft (15,440 m), which was homologated as 49,967 ft (15,230 m). After this milestone, research flights continued, along with further attempts to break the altitude record. Further development of the aircraft after the first record-breaking flight led to a series of small modifications being implemented. The last record-breaking flight was flown on 30 June 1937. A second aircraft, designated as the Type 138B, was ordered in 1935 but work on it was abandoned during 1937 without ever having flown.
Bristol 1438a.jpg
Bristol 138A.jpg
Britol 138a=.jpg
General characteristics
  • Crew: one
  • Length: 44 ft 0 in (13.41 m)
  • Wingspan: 66 ft 0 in (20.12 m)
  • Height: 10 ft 3 in (3.13 m)
  • Wing area: 568 ft² (52.8 m²)
  • Empty weight: 4,391 lb (1,996 kg)
  • Loaded weight: 5,310 lb (2,414 kg)
  • Powerplant: 1 × Bristol Pegasus P.E.6S radial, 500 hp (373 kW)
Type 138B One built to use a Rolls-Royce Kestrel S engine, never flown and became a ground instructional aircraft
  • Maximum speed: 107 kn (123 mph, 198 km/h)
  • Service ceiling: 54,000 ft (16,500 m)
  • Rate of climb: 1,430 ft/min (7.27 m/s) at 40,000 ft
  • Wing loading: 9.35 lb/ft² (45.7 kg/m²)
  • Power/mass: 0.0942 hp/lb (0.155 kW/kg)
  • Endurance: 2¼ hours
  • Bristol Type 138
  • During 1935, a second machine was ordered, designated the Type 138B.[3] This was to be a two-seater aircraft, powered by a Rolls-Royce Kestrel S engine, which would be fitted with a similar two-stage supercharger installation, enabling it to generate 500 hp (370 kW). In 1937, the airframe was delivered to Farnborough Airfield for completion, but the engine installation was never completed.[6] The Type 138B was used as a ground instructional trainer instead, and accordingly never flew.[3]

Users who are viewing this thread