De Havilland Comet

De Havilland Comet

The de Havilland DH 106 Comet was the first production commercial jetliner. Developed and manufactured by de Havilland at its Hatfield, Hertfordshire, United Kingdom headquarters, the Comet 1 prototype first flew on 27 July 1949. It featured an aerodynamically clean design with four de Havilland Ghost turbojet engines buried in the wings, a pressurised fuselage, and large square windows. For the era, it offered a relatively quiet, comfortable passenger cabin and showed signs of being a commercial success at its 1952 debut.

A year after entering commercial service, Comet airframes began suffering catastrophic metal fatigue, with three of them tearing apart during mid-flight in well-publicised accidents. The Comet was withdrawn from service and extensively tested to discover the cause; the first incident had been incorrectly blamed on adverse weather. Design flaws including window shape and installation methodology were ultimately identified; consequently the Comet was extensively redesigned with oval windows, structural reinforcement and other changes. Rival manufacturers meanwhile heeded the lessons learned from the Comet while developing their own aircraft.

Although sales never fully recovered, the improved Comet 2 and the prototype Comet 3 culminated in the redesigned Comet 4 series which debuted in 1958 and enjoyed a productive career of over 30 years. The Comet was adapted for a variety of military roles such as VIP, medical and passenger transport, as well as surveillance; the most extensive modification resulted in a specialised maritime patrol aircraft variant, the Hawker Siddeley Nimrod. Nimrods remained in service with the Royal Air Force (RAF) until they were retired in June 2011, over 60 years after the Comet's first flight.