The Bristol Type 167 Brabazon was a large British piston-engined propeller-driven airliner designed by the Bristol Aeroplane Company to fly transatlantic routes between the UK and the United States. The type was named Brabazon after the Brabazon Committee and its chairman, Lord Brabazon of Tara, which had developed the specification to which the airliner was designed.
The committee, which had become known simply as the Brabazon Committee, delivered its report, which was likewise known as the Brabazon Report. The report called for the construction of a total of four of five designs they had studied. Of those designs, the Type I was a very large transatlantic airliner, the Type II was a short-haul airliner, the Type III was a medium-range airliner for the multiple-hop "Empire" air routes, and the Type IV was an innovative jet-powered 500 mph (800 km/h) airliner. In particular, the Type I and Type IV were regarded as being of very high importance to the industry, particularly the jet-powered Type IV, which would give Britain a commanding lead in the field of jet transport. An outline of the specifications for the various envisioned aircraft, including the gigantic Type I, was issued by the Committee. Additionally, Bristol's design team had already been considering the requirements of an aircraft capable of conducting routine transatlantic flights, which had led to projections of the necessary size, weight and range of such an airliner. Amongst those, it was determined that, in order to be profitable, a minimum payload of 100 passengers should be carried by the type.
In 1942, the Air Ministry issued a draft operational requirement from the Air Staff, which sought a heavy bomber design that would be capable of carrying a payload of at least 15 tons of bombs. In response, Bristol dusted off their original work and updated it to incorporate their newer and substantially more powerful Bristol Centaurus engines. The Bristol design team, led by L. G. Frise and Archibald Russell, worked with several key performance parameters. Those included a range of 5,000 mi (8,000 km), 225 ft (69 m) wingspan, eight engines buried in the wings driving four pusher propeller installations, and enough fuel for transatlantic range. The Convair B-36 was in many ways the American equivalent of that projected "100-ton bomber".
In 1942, the Brabazon Report was published and Bristol chose to respond, submitting a slightly modified version of their bomber to fulfil the Type I requirement. Bristol's earlier work had demonstrated the sort of performance that the Brabazon Committee had been looking for, and so the Committee authorised the firm to begin preliminary design of such an aircraft that year, with the proviso that work on wartime aircraft should not be disrupted by the project.
Bristol 167
In November 1944, after further work on the design, a final concept for the Type 167 was published. The final design featured a large 177 ft (54 m) fuselage, paired with a sizable wing. The wing, which had a 230 ft (70.1 m) wingspan, possessed an enormous internal volume, to house sufficient fuel for the transatlantic flights envisioned for the type.
The Brabazon Report had assumed that the wealthy people flying in the aircraft would consider a long trip by air to be uncomfortable, and so designed the Type I for luxury, demanding 200 ft<sup>3</sup> (6 m<sup>3</sup>) of space for every passenger, which was expanded to 270 ft<sup>3</sup> (8 m<sup>3</sup>) for luxury class. If outfitted with conventionally spaced seating, the dimensions of the Type 167 could have accommodated up to 300 passengers, instead of the 60 seats opted for.
To meet these varied requirements, the Type 167 specified a huge -diameter fuselage, which was about 5 ft (1.5 m) greater than the 1970 Boeing 747 "jumbo jet", with full-length upper and lower decks. That enclosed sleeping berths for 80 passengers, a dining room, 37-seat cinema, promenade and bar or, alternatively, day seats for 150 people. At one point, the Committee recommended the adoption of a narrower fuselage to house a total of 50 passengers. The British Overseas Airways Corporation (BOAC) agreed with that recommendation, and also expressed its preference for a design accommodating only 25 passengers. In August 1943, an agreement with the airline led to the selection of an interior layout which contained a forward area housing six compartments, each one for six passengers, along with a seventh compartment for just three passengers, a midsection above the wing – the wing was deep at that point – which accommodated 38 seats arranged around tables in groups of four along with a pantry and galley, and a rear area with 23 seats in an aft-facing cinema, complete with a cocktail bar and lounge. Similar to the Saunders-Roe Princess, the Brabazon concept was a fusion of prewar and postwar thinking, using highly advanced design and engineering to build an aircraft that was no longer relevant in the postwar world.
The Brabazon was the first aircraft to be outfitted with 100 per cent powered flying controls; it was also the first with electric engine controls, and the first equipped with high-pressure hydraulics. The large span and mounting of the engines close inboard, together with structural weight economies, demanded some new measure to prevent bending of wing surfaces in turbulence. One of the innovative features of the Brabazon was a purpose-developed gust-alleviation system, which used an assortment of servos that were triggered from a gust-sensing probe installed on the exterior of the aircraft's nose; an improved version of this system, along with fully automated trimming, was to have been deployed on the Brabazon Mark II.