 | De Havilland Comet: Encyclopedia - De Havilland Comet
De Havilland Comet
This article deals with the de Havilland Comet jet airliner. For the 1930s racing aircraft see de Havilland DH.88
The de Havilland Comet of Britain was the world's first commercial jet airliner. It is infamous for being the first to experience the metal fatigue of jet aircraft due to high flight altitudes.
De Havilland Comet - History
Design work began in 1946 under Ronald Bishop and the intention was to have a commercial aircraft by 1952. The DH 106 Comet first flew on July 27, 1949. The design was similar to other airliners except that four of the new, albeit underpowered, de Havilland Ghost 50 turbojets were mounted within the wings, in pairs close to the fuselage. The airliner underwent almost three years of tests and fixes and the first commercial flights did not begin until January 22, 1952 with BOAC. The first passenger flight was in May from London Heathrow Airport to Johannesburg. The airliner proved to be around twice as fast as contemporary craft and with almost 30,000 passengers carried in the first year over fifty Comets were ordered.
De Havilland Comet - Design flaws
The first sign of a flaw in the Comet came on May 2, 1953 when a Comet crashed soon after take-off from Calcutta; further crashes (January and April 1954) with no clear cause led to the entire fleet being grounded for investigation. Only after the remnants of the Italian crash were brought to the surface and analysed was it found in February 1955 that, as suspected, metal fatigue was the problem: after thousands of pressurised climbs and descents, the thin fuselage metal around the Comet's distinctive rectangular, large windows would begin to crack and eventually cause explosive decompression of the cabin and catastrophic structural failure.
All remaining Comets were either scrapped or modified with window rip-stop doublers and the program to produce a Comet 2 with more powerful Rolls-Royce Avon engines was put on hold. Some Comet 2s were modified to alleviate the fatigue problems and served with the RAF as the Comet C.2.
De Havilland Comet - Comet 4
The Comet did not resume commercial airline service until 1958, when the much-improved Comet 4 was introduced.
The Comet 4 included many modifications compared to the original Comet 1. It used a strengthened fuselage and round windows to alleviate the metal fatigue problems of the Comet 1. The Comet 4 was also a considerably larger aircraft, 5.64 m (18 ft 6 in) longer than the Comet 1 and typically seating 74 to 81 passengers, compared to the Comet 1's 36 to 44. It also had a longer range, higher cruising speed, and higher maximum takeoff weight. These improvements were possible largely due to the use of Rolls-Royce Avon engines with over twice the thrust of the Comet 1's de Havilland Ghosts.
BOAC ordered 19 Comet 4s in March 1955, despite the Comet 1's problems. The Comet 4 first flew on April 27, 1958, and deliveries to BOAC began that September. BOAC initiated Comet 4 service with a flight from London to New York via Gander on October 4, 1958. That flight was the first scheduled trans-Atlantic passenger jet service, beating Pan Am's inaugural 707 service by three weeks.
De Havilland Comet - Comet 4B and 4C
Two other variants of the Comet 4 were developed. The Comet 4B included a stretched fuselage and shorter wings; it was targeted to the fairly short-range operations of British European Airways, which placed an initial order for it in 1958. The Comet 4B first flew on June 27, 1959, and BEA inaugurated services with it in April 1960. The final Comet 4 variant was the Comet 4C, with the longer fuselage of the Comet 4B but the larger wings and fuel tanks of the original Comet 4, which gave it a longer range than the 4B. It first flew on October 31, 1959, and Mexicana started Comet 4C services in 1960.
Examples are on display at the Mosquito Aircraft Museum.
De Havilland Comet - Hawker-Siddeley Nimrod
The Nimrod, a military Electronic Reconnaissance and maritime patrol aircraft, is a larger and heavily modified variation of the Comet 4 design that entered service in 1967 and is only now reaching the end of its service life.
De Havilland Comet - Production and service summary
In total, 76 Comet 4 family aircraft were delivered from 1958 to 1964. Although BOAC retired its Comet 4s from revenue service in 1965, other operators (of which Dan-Air was the largest and last) continued flying commercial passenger services with the aircraft until 1980. The last Comet flight was conducted in 1997 by a Comet 4C that had been owned by the British government.
Although the Comet was the first jet airliner in service, the interruption of commercial service and the damage to the aircraft's reputation caused by the Comet 1 fatigue failures meant that the jetliner market was dominated by Boeing, which flew the first prototype 707 in 1954, and Douglas, which launched the DC-8 program in 1955. Additionally both types had superior range and passenger accommodations compared to the Comet. America would enjoy a near-monopoly of the commercial jetliner market for the next 40 years. Only in the mid-2000s has Europe regained competitiveness with accession of Airbus.
Only fifteen airlines ever used the Comet, the proposed Comet 5 was never built, and the Comet 4s were slowly withdrawn from service.
Perhaps as a mark of respect, a preserved Comet 4 in BOAC livery is on display at the Museum of Flight, next to Boeing's Seattle factory.
In addition, it is notable that a Comet 4C in the colours of Dan-Air is on display at the Imperial War Museum Duxford, England. The plane is part of the Flight Line Display and made available for touring inside during specific times.
De Havilland Comet - Units using the Comet
De Havilland Comet - Royal Air Force
- No. 2 Squadron
- No. 4 Squadron
- No. 51 Squadron
- No. 192 Squadron
- No. 216 Squadron
De Havilland Comet - Related content
Related development:
Similar aircraft:
Related lists:
Lists of Aircraft | Aircraft manufacturers | Aircraft engines | Aircraft engine manufacturers
Airports | Airlines | Air forces | Aircraft weapons | Missiles | Timeline of aviation
Lists of Aircraft | Aircraft manufacturers | Aircraft engines | Aircraft engine manufacturers
Airports | Airlines | Air forces | Aircraft weapons | Missiles | Timeline of aviation
Categories: British airliners 1940-1949 | British military transport aircraft 1950-1959 | In-flight airliner structural failures
Other related archives1930s, 1949, 1952, 1953, 1958, 1959, 1960, 2000s, 707, Air forces, Airbus, Aircraft, Aircraft engine manufacturers, Aircraft engines, Aircraft manufacturers, Aircraft weapons, Airlines, Airports, April 27, Avon, BOAC, Boeing, Britain, British European Airways, British airliners 1940-1949, British military transport aircraft 1950-1959, Calcutta, DC-8, Dan-Air, Douglas, Gander, Imperial War Museum, In-flight airliner structural failures, January 22, Johannesburg, July 27, June 27, List of airliners, London Heathrow Airport, May 2, Mexicana, Missiles, Mosquito Aircraft Museum, Museum of Flight, Nimrod, No. 2 Squadron, No. 216 Squadron, No. 4 Squadron, No. 51 Squadron, October 4, Pan Am, RAF, Rolls-Royce, Sud Aviation Caravelle, Timeline of aviation, Tupolev Tu-104, airliner, de Havilland, de Havilland DH.88, explosive decompression, jet, jet airliner, metal fatigue, turbojets
 Adapted from the Wikipedia article "De Havilland Comet", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki |
