Bristol Brabazon
Encyclopedia
The Bristol Type 167 Brabazon was a large propeller
-driven 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 airliner 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
.
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. The Convair B-36
was in many ways the American analogue of this "100 ton bomber" and designs from the other major manufacturers. 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.
18-cylinder radial engine
s nested in pairs in the wing. These drove eight paired contra-rotating propellers
on four forward-facing nacelles.
The Brabazon Report assumed that the wealthy flying the aircraft would consider a long trip by air to be uncomfortable, and they designed the Type I for luxury, demanding 200 ft³ (6 m³) of room for every passenger, and 270 ft³ (8 m³) for luxury. This is similar to the interior room of a small car.
To meet these requirements the Type 167 specified a huge 25 ft (8 m)-diameter fuselage, which is about 5 ft (1.5 m) greater than a 747, with full-length upper and lower decks. This enclosed sleeping berths for 80 passengers, a dining room, 37-seat cinema, promenade and bar; or day seats for 150 people. The Committee recommended a narrower fuselage designed for 50 passengers. BOAC
agreed, but preferred a design for only 25 passengers. An agreement with the airline eventually led to an interior layout housing a forward area with six compartments, each for six passengers and a seventh for just three; a mid-section above the wing - the wing was 6 feet deep at that point - with 38 seats arranged around tables in groups of four with a pantry
and galley; and a rear area with 23 seats in an aft-facing cinema with a cocktail bar and lounge. Like the Saunders-Roe Princess
, the Brabazon concept was a fusion of pre-war and post-war thinking, using highly advanced design and engineering to build an aircraft that was no longer required in the post-war world.
A tremendous effort was put into saving weight. The Type 167 used a number of non-standard gauges of skinning in order to tailor every panel to the strength required, thereby saving several tons of metal. 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. A system of gust alleviation was developed for the Brabazon, using servos triggered from a probe in the aircraft's nose. Hydraulic power units were also designed to operate the giant control surfaces. The Brabazon was the first aircraft with 100% powered flying controls, the first with electric engine controls, and the first with high-pressure hydraulics.
Building the aircraft was a challenge. Bristol's existing factory in Filton
was too small to handle what was one of the largest aircraft in the world, and the 2,000 ft (610 m) runway was too short to launch it. Construction of the first prototype's fuselage started in October 1945 in an existing hangar
while a gigantic hall for final assembly was built, whose designer, T. P. O'Sullivan
, was awarded the Telford Premium
for the work. The runway was lengthened to 8,000 ft (2,440 m), which required moving elsewhere the inhabitants of the village of Charlton
.
Some design and construction work was shared out to other British companies such as Folland Aircraft.
engines - eight paired turboprops driving 4-bladed screws through a common gearbox. This would increase cruising speed from 260 to 330 mph (420–530 km/h) and ceiling while reducing the empty weight by about 10,000 lb (4,540 kg). This Brabazon Mark II, would be able to cross the Atlantic (London-New York) in a reduced time of 12 hours.
Although the Proteus was slimmer than the Centaurus, the wing thickness was not to be reduced in the Mark II but the leading edge would be extended around the engines.
Changes to the wheel arrangement planned for the Mark II would have allowed it to use most runways on both the North Atlantic and Empire routes.
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 takeoff, clean configuration flypast 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.
) 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. 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 National 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.
Propeller (aircraft)
Aircraft propellers or airscrews convert rotary motion from piston engines or turboprops to provide propulsive force. They may be fixed or variable pitch. Early aircraft propellers were carved by hand from solid or laminated wood with later propellers being constructed from metal...
-driven airliner
Airliner
An airliner is a large fixed-wing aircraft for transporting passengers and cargo. Such aircraft are operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an aircraft intended for carrying multiple passengers in commercial...
, designed by the Bristol Aeroplane Company
Bristol Aeroplane Company
The Bristol Aeroplane Company, originally the British and Colonial Aeroplane Company, was both one of the first and one of the most important British aviation companies, designing and manufacturing both airframes and aero engines...
to fly transatlantic
Transatlantic flight
Transatlantic flight is the flight of an aircraft across the Atlantic Ocean. A transatlantic flight may proceed east-to-west, originating in Europe or Africa and terminating in North America or South America, or it may go in the reverse direction, west-to-east...
routes from the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
to the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. The prototype was delivered in 1949, only to prove a commercial failure when airlines felt the airliner was too large and expensive to be useful. Despite its size, comparable to a Boeing 767
Boeing 767
The Boeing 767 is a mid-size, wide-body twin-engine jet airliner built by Boeing Commercial Airplanes. It was the manufacturer's first wide-body twinjet and its first airliner with a two-crew glass cockpit. The aircraft features two turbofan engines, a supercritical wing, and a conventional tail...
, 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
Fuselage
The fuselage is an aircraft's main body section that holds crew and passengers or cargo. In single-engine aircraft it will usually contain an engine, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage which in turn is used as a floating hull...
.
Background
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
Brabazon Committee
The Brabazon Committee was a committee formed on 23 December 1942 to investigate the future needs of the British Empire's civilian airliner market...
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
British Empire
The British Empire comprised the dominions, colonies, protectorates, mandates and other territories ruled or administered by the United Kingdom. It originated with the overseas colonies and trading posts established by England in the late 16th and early 17th centuries. At its height, it was the...
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
Bomber
A bomber is a military aircraft designed to attack ground and sea targets, by dropping bombs on them, or – in recent years – by launching cruise missiles at them.-Classifications of bombers:...
design starting as early as 1937, but nothing had come of this. In 1942 the Air Ministry
Air Ministry
The Air Ministry was a department of the British Government with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964...
published a tender for a new super-heavy bomber
Heavy bomber
A heavy bomber is a bomber aircraft of the largest size and load carrying capacity, and usually the longest range.In New START, the term "heavy bomber" is used for two types of bombers:*one with a range greater than 8,000 kilometers...
design, and Bristol dusted off their original work and updated it for their newer and much more powerful Bristol Centaurus
Bristol Centaurus
|-See also:-Bibliography:*Bridgman, L, Jane's Fighting Aircraft of World War II. Crescent. ISBN 0-517-67964-7*Gunston, Bill. Development of Piston Aero Engines. Cambridge, England. Patrick Stephens Limited, 2006. ISBN 0-7509-4478-1...
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
Pusher configuration
In a craft with a pusher configuration the propeller are mounted behind their respective engine. According to Bill Gunston, a "pusher propeller" is one mounted behind engine so that drive shaft is in compression...
propeller installations, and enough fuel for transatlantic range. The Convair B-36
Convair B-36
The Convair B-36 "Peacemaker" was a strategic bomber built by Convair and operated solely by the United States Air Force from 1949 to 1959. The B-36 was the largest mass-produced piston engine aircraft ever made. It had the longest wingspan of any combat aircraft ever built , although there have...
was in many ways the American analogue of this "100 ton bomber" and designs from the other major manufacturers. However in expectation of long development times, the Air Ministry later changed their mind and decided to continue development of the Avro Lancaster
Avro Lancaster
The Avro Lancaster is a British four-engined Second World War heavy bomber made initially by Avro for the Royal Air Force . It first saw active service in 1942, and together with the Handley Page Halifax it was one of the main heavy bombers of the RAF, the RCAF, and squadrons from other...
, (leading to the Avro Lincoln
Avro Lincoln
The Avro Type 694, better known as the Avro Lincoln, was a British four-engined heavy bomber, which first flew on 9 June 1944. Developed from the Avro Lancaster, the first Lincoln variants were known initially as the Lancaster IV and V, but were renamed Lincoln I and II...
) instead.
Bristol 167
A year later, the Brabazon Report was published and Bristol was able to respond with a slightly modified version of their bomber to fill the needs for the Type I requirement. Their earlier work was the sort of performance the Brabazon committee was looking for, and they were given a contract for two prototype aircraft. After further work on the design, a final concept was published in November 1944. It was for a 177 ft (54 m) fuselage with 230 ft (70.1 m) wingspan (35 ft/11 m greater than a Boeing 747) powered by eight Bristol CentaurusBristol Centaurus
|-See also:-Bibliography:*Bridgman, L, Jane's Fighting Aircraft of World War II. Crescent. ISBN 0-517-67964-7*Gunston, Bill. Development of Piston Aero Engines. Cambridge, England. Patrick Stephens Limited, 2006. ISBN 0-7509-4478-1...
18-cylinder radial engine
Radial engine
The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes on a wheel...
s nested in pairs in the wing. These drove eight paired contra-rotating propellers
Contra-rotating propellers
Aircraft equipped with contra-rotating propellers, also referred to as coaxial contra-rotating propellers, apply the maximum power of usually a single piston or turboprop engine to drive two propellers in contra-rotation...
on four forward-facing nacelles.
The Brabazon Report assumed that the wealthy flying the aircraft would consider a long trip by air to be uncomfortable, and they designed the Type I for luxury, demanding 200 ft³ (6 m³) of room for every passenger, and 270 ft³ (8 m³) for luxury. This is similar to the interior room of a small car.
To meet these requirements the Type 167 specified a huge 25 ft (8 m)-diameter fuselage, which is about 5 ft (1.5 m) greater than a 747, with full-length upper and lower decks. This enclosed sleeping berths for 80 passengers, a dining room, 37-seat cinema, promenade and bar; or day seats for 150 people. The Committee recommended a narrower fuselage designed for 50 passengers. BOAC
Boac
Boac may refer to:* Boac, Marinduque, a municipality in the Southern Philippines* Boac , an American rapper* British Overseas Airways Corporation, a former British state-owned airline...
agreed, but preferred a design for only 25 passengers. An agreement with the airline eventually led to an interior layout housing a forward area with six compartments, each for six passengers and a seventh for just three; a mid-section above the wing - the wing was 6 feet deep at that point - with 38 seats arranged around tables in groups of four with a pantry
Pantry
A pantry is a room where food, provisions or dishes are stored and served in an ancillary capacity to the kitchen. The derivation of the word is from the same source as the Old French term paneterie; that is from pain, the French form of the Latin panis for bread.In a late medieval hall, there were...
and galley; and a rear area with 23 seats in an aft-facing cinema with a cocktail bar and lounge. Like the Saunders-Roe Princess
Saunders-Roe Princess
-See also:-Bibliography:* Bridgman, Leonard. Jane's All The World's Aircraft 1952-53. London: Jane's, 1953.* . Flight, 6 July 1951. pp. 10–11.* Flight, 16 March 1950, pp. 344–345....
, the Brabazon concept was a fusion of pre-war and post-war thinking, using highly advanced design and engineering to build an aircraft that was no longer required in the post-war world.
A tremendous effort was put into saving weight. The Type 167 used a number of non-standard gauges of skinning in order to tailor every panel to the strength required, thereby saving several tons of metal. 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. A system of gust alleviation was developed for the Brabazon, using servos triggered from a probe in the aircraft's nose. Hydraulic power units were also designed to operate the giant control surfaces. The Brabazon was the first aircraft with 100% powered flying controls, the first with electric engine controls, and the first with high-pressure hydraulics.
Building the aircraft was a challenge. Bristol's existing factory in Filton
Filton
Filton is a town in South Gloucestershire, England, situated on the northern outskirts of the city of Bristol, about from the city centre. Filton lies in Bristol postcode areas BS7 and BS34. The town centres upon Filton Church, which dates back to the 12th century and is a grade II listed building...
was too small to handle what was one of the largest aircraft in the world, and the 2,000 ft (610 m) runway was too short to launch it. Construction of the first prototype's fuselage started in October 1945 in an existing hangar
Hangar
A hangar is a closed structure to hold aircraft or spacecraft in protective storage. Most hangars are built of metal, but other materials such as wood and concrete are also sometimes used...
while a gigantic hall for final assembly was built, whose designer, T. P. O'Sullivan
Terence Patrick O'Sullivan
Terence Patrick O'Sullivan BSc, PhD, FICE, MSocCE , was a civil engineer. He specialised initially in steel and reinforced concrete structures. Later he founded a firm of consulting engineers, T. P...
, was awarded the Telford Premium
Institution of Civil Engineers
Founded on 2 January 1818, the Institution of Civil Engineers is an independent professional association, based in central London, representing civil engineering. Like its early membership, the majority of its current members are British engineers, but it also has members in more than 150...
for the work. The runway was lengthened to 8,000 ft (2,440 m), which required moving elsewhere the inhabitants of the village of Charlton
Charlton, Bristol
Charlton was the name of a small village in Gloucestershire, England, demolished in the late 1940s. It was located between Filton and Cribbs Causeway immediately north of Bristol.-History:...
.
Some design and construction work was shared out to other British companies such as Folland Aircraft.
Mark II
In 1946 it was decided to make the second prototype based on the Bristol Coupled Proteus turbopropTurboprop
A turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...
engines - eight paired turboprops driving 4-bladed screws through a common gearbox. This would increase cruising speed from 260 to 330 mph (420–530 km/h) and ceiling while reducing the empty weight by about 10,000 lb (4,540 kg). This Brabazon Mark II, would be able to cross the Atlantic (London-New York) in a reduced time of 12 hours.
Although the Proteus was slimmer than the Centaurus, the wing thickness was not to be reduced in the Mark II but the leading edge would be extended around the engines.
Changes to the wheel arrangement planned for the Mark II would have allowed it to use most runways on both the North Atlantic and Empire routes.
Testing
The Mk.I aircraft, registration G-AGPW, rolled out for engine runs in December 1948, and flew for the first time, over AvonmouthAvonmouth
Avonmouth is a port and suburb of Bristol, England, located on the Severn Estuary, at the mouth of the River Avon.The council ward of Avonmouth also includes Shirehampton and the western end of Lawrence Weston.- Geography :...
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 takeoff, clean configuration flypast 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
Paris Air Show
The Paris Air Show is the world's oldest and largest air show. Established in 1909, it is currently held every odd year at Le Bourget Airport in north Paris, France...
. 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
British European Airways
British European Airways or British European Airways Corporation was a British airline which existed from 1946 until 1974. The airline operated European and North African routes from airports around the United Kingdom...
on flying the prototype itself, various problems that would be expected of a prototype meant it never received an airworthiness certificate.
Cancellation
By 1952, about £3.4m had been spent on development (£53.4m 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 SandysDuncan Sandys
Edwin Duncan Sandys, Baron Duncan-Sandys CH PC was a British politician and a minister in successive Conservative governments in the 1950s and 1960s...
) 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. 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
Bristol Industrial Museum
The Bristol Industrial Museum was a museum in Bristol, England, located on Prince's Wharf beside the Floating Harbour, and which closed in 2006. On display were items from Bristol's industrial past – including aviation, car and bus manufacture, and printing – and exhibits documenting Bristol's...
and Scotland's National Museum of Flight.
White elephant
A white elephant is an idiom for a valuable but burdensome possession of which its owner cannot dispose and whose cost is out of proportion to its usefulness or worth...
, 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
Bristol Britannia
The Bristol Type 175 Britannia was a British medium-to-long-range airliner built by the Bristol Aeroplane Company in 1952 to fly across the British Empire...
. Using all of the advancements of the Brabazon meant the Britannia had the best payload fraction
Payload fraction
In aerospace engineering, payload fraction is a common term used to characterize the efficiency of a particular design. Payload fraction is calculated by dividing the weight of the payload by the weight of the otherwise empty aircraft when fully fueled...
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
De Havilland Comet
The de Havilland DH 106 Comet was the world's first commercial jet airliner to reach production. Developed and manufactured by de Havilland at the Hatfield, Hertfordshire, United Kingdom headquarters, it first flew in 1949 and was a landmark in aeronautical design...
, it went on to be a workhorse for many airlines into the 1970s.
Specifications (Mark I)
See also
- Convair XC-99Convair XC-99The Convair XC-99, 43-52436, was a prototype heavy cargo aircraft built by Convair for the United States Air Force. It was the largest piston-engined land-based transport aircraft ever built, and was developed from the B-36 bomber, sharing the wings and some other structures with it...
- Hughes H-4 HerculesHughes H-4 HerculesThe Hughes H-4 Hercules is a prototype heavy transport aircraft designed and built by the Hughes Aircraft company. The aircraft made its only flight on November 2, 1947 and the project was never advanced beyond the single example produced...
- Saunders-Roe PrincessSaunders-Roe Princess-See also:-Bibliography:* Bridgman, Leonard. Jane's All The World's Aircraft 1952-53. London: Jane's, 1953.* . Flight, 6 July 1951. pp. 10–11.* Flight, 16 March 1950, pp. 344–345....