Tuesday 22 December 2009


The Bristol Type 167 Brabazon was a large airliner, designed by the Bristol Aeroplane Company to fly transatlantic routes from the United Kingdom to the United States. The prototype was delivered in 1949, only to prove a commercial failure when airlines felt the plane was too large and expensive to be useful. Despite its size, comparable to a Boeing 767, it was designed to carry only 100 passengers, albeit in roomy conditions not generally found on modern aircraft. In the end, only a single prototype was flown; it was broken up in 1953 for scrap, along with an uncompleted second fuselage


In 1943, a British government committee met under the leadership of Lord Brabazon of Tara to investigate the needs of the British civil airliner market.

The Brabazon Committee delivered a report, known as the "Brabazon Report", calling for the construction of four of five designs they had studied. Type I was a large transatlantic airliner, Type III a smaller airliner for the Empire air routes, and Type IV a jet powered 500 mph (800 km/h) airliner. The Type I and IV were considered to be very important to the industry, notably the jet powered Type IV which would give the UK a commanding lead in jet transports.

Bristol had already studied a large bomber design starting as early as 1937, but nothing had come of this. In 1942 the Air Ministry published a tender for a new super-heavy bomber design, and Bristol dusted off their original work and updated it for their newer and much more powerful Bristol Centaurus engines. This led to a design with a range of 5,000 mi (8,000 km), 225 ft (69 m) wing span, eight engines buried in the wings driving four pusher propeller installations, and enough fuel for transatlantic range. This "100 ton bomber" and designs from the other major manufacturers were in many ways the British analogues to the American Convair B-36. However in expectation of long development times, the Air Ministry later changed their mind and decided to continue development of the Avro Lancaster, (leading to the Avro Lincoln) instead.


The Mk.I aircraft, registration G-AGPW, rolled out for engine runs in December 1948, and flew for the first time, over Avonmouth for 25 minutes, on 4 September 1949 captained by Bristol Chief Test Pilot Bill Pegg. It flew to about 3,000 ft (910 m) at 160 mph (257 km/h) and landed at 115 mph (185 km/h), throttling back at 50 ft (15 m). Four days later, it was presented at the Farnborough Airshow before starting testing in earnest. It was demonstrated at the 1950 Farborough Airshow with a take-off, clean configuration fly-past and a landing. In June 1950, she visited London's Heathrow Airport, making a number of successful takeoffs and landings, and was demonstrated at the 1951 Paris Air Show. By this point, BOAC had lost any interest in the design, if it ever really had any, and although some interest was shown by BEA on flying the prototype itself, various problems that would be expected of a prototype meant it never received an airworthiness certificate.


By 1952, about £3.4m had been spent on development (£53.4m year in year-2000 pounds) and it showed no signs of being purchased by any airline. In March, the British government announced that work on the second prototype had been postponed. The cancellation of the project was announced by the Minister for Supply (Duncan Sandys) on 17 July 1953 in the Commons saying that it had given all the useful technical knowledge it could but with no interest from civil or the military they had no justification for continuing to spend money on it. About 6 million pounds had been spent and a further 2 would be required for the completion of the Mark II. The buildings and runway had cost a further £6 million.[4] In October 1953, after 164 flights totalling 382 hours flying time, the first prototype was broken up, along with the uncompleted Mk.II prototype. All that remains are a few parts at the Bristol Industrial Museum and Scotland's Museum of Flight.

Although considered a failure and a white elephant, the record of the Brabazon is not entirely unfavourable. At least half of the large sums spent on the project were put into infrastructure, including the large hangars and runway at Filton. This meant that Bristol was now in an excellent position to continue production of other designs and the hall was used for building the Britannia aircraft. In addition, many of the techniques developed as a part of the Brabazon project were applicable to any aircraft, not just airliners.

Bristol had also won the contract for the "unimportant" Type III aircraft, which they delivered as the Bristol Britannia. Using all of the advancements of the Brabazon meant the Britannia had the best payload fraction of any aircraft up to that point, and it kept that record for a number of years. Although the Britannia was delayed after problems with the Type IV, the de Havilland Comet, it went on to be a workhorse for many airlines into the 1970s. The Britannia is still considered by many[who?] to be the ultimate propeller driven airliner.[citation needed]

Specifications (Mark I)

Data from Flight

General characteristics

  • Crew: 6-12
  • Capacity: 100 passengers [5]
  • Length: 177 ft (54.0 m)
  • Wingspan: 230 ft (70 m)
  • Height: 50 ft (15 m)
  • Wing area: 5,317 ft² (494.0 m²)
  • Airfoil: Root T.P.4 (mod) Tip T.P.5
  • Empty weight: 145,100 lb (65,820 kg)
  • Max takeoff weight: 290,000 lb (130,000 kg)
  • Powerplant:Bristol Centaurus radial engines, 2,650 hp (1,860 kW) each
  • Propellers: paired contra-rotating 3-bladed Rotol
    • Propeller diameter: 16 ft ()
  • Fuel capacity 13,650 Imp gal



About Centaurus Engines

To achieve the necessary reduction in drag and also achieve the design criteria, i.e. non-stop across the Atlantic with 100 passengers, a serious rethink was needed. Bristol had done some initial design work for the aborted Type 159 long-range bomber. This had been a 100 ton bomber with a range up to 5000 miles.

Analysis of the current designs showed that conventional wing mounted engines accounted for 30% of the overall drag, although only 5% was needed for cooling. It became clear to the design team that power plants completely submerged in the wing were thus likely to reduce total drag by 25%, if technically feasible.

The wing would have to be at least as thick as the height of the engine, and coupling several engines side by side to a single airscrew would leave the outer wing free from interference and available for fuel storage. By using this method the larger range required could be easily achieved.


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