Two DH-88 Comets, G-ACSS and G-ACSP, survived into preservation, while a number of full-scale replicas have also been constructed.ĭuring 1933, the MacRobertson Air Race, a long distance multi-stage journey from the United Kingdom to Australia, was being planned for October 1934, to celebrate the 100th anniversary of the Australian State of Victoria. Several examples were bought and evaluated by national governments, typically as mail planes. The DH-88 Comet went on to establish a multitude of aviation records, both during the race and in its aftermath, as well as participating in further races. DH-88 Comet G-ACSS Grosvenor House emerged as the winner. The aircraft underwent a rapid development cycle, performing its maiden flight only six weeks prior to the race. Three DH-88 Comets were produced for the race, all for private owners at the discounted price of £5,000 per aircraft. Hagg around the specific requirements of the race Hagg produced an innovative design in the form of a stressed-skin cantilever monoplane, complete with an enclosed cockpit, retractable undercarriage, landing flaps, and variable-pitch propellers. It was developed specifically to participate in the 1934 England-Australia MacRobertson Air Race from the United Kingdom to Australia.ĭevelopment of the DH-88 Comet was initiated at the behest of British aviation pioneer Geoffrey de Havilland, along with the support of de Havilland’s board, being keen to garner prestige from producing the victorious aircraft as well as to gain from the research involved in producing it. The de Havilland DH-88 Comet is a British two-seat, twin-engined aircraft built by the de Havilland Aircraft Company. Status: One airworthy one in restoration.
The actual number of pressurised flights was 1290.Twin-engine Two-seat Low-wing Long-distance Racing Monoplane, U.K.ĭe Havilland DH-88 Comet (N88XD, G-ACSS, replica) on display (c.1994) at the Hawthorne Air Faire, Hawthorne, California (35mm photo by John Shupek copyright © 2000 Skytamer Images)ĭe Havilland DH-88 Comet (G-ACSS, original) on display 10 September 2002 at the Shuttleworth Collection, Old Warden Aerodrome, Nr Biggleswade, Bedfordshire, England (Photo by John Shupek copyright © 2002 Skytamer Images)
#De havilland comet crack
Crack growth analysis calculated the life of "YP" as 1272 cycles. As such, the material behaved slightly worse than current similar alloys. Using the data from the 1950’s, it was calculated: parameter A = 49.5 MPa m^(1/2) and exponent m = 5. The presentation revisits the Comet case and shows a modern investigation based on the research done in the 1950th and the "Paris Law" from 1963 which allows the calculation of crack growth. It remained in service as the Nimrod until 60 years after first Comet flight. The Comet was the first airliner to fly a scheduled service across the Atlantic on 4th October 1958. The Comet flew again as the Comet IV with different window design.
#De havilland comet skin
The interaction of the skin stresses and the manufacturing defects was beyond the scientific knowledge base of the early 1950s. The bolt hole which failed on "YP" had a defect in the chamfer which indicated the potential for manufacturing defects on all skin holes.
#De havilland comet windows
The square windows were the cause of high stresses. The accident was caused by structural failure of the pressure cabin, brought about by fatigue. It was found that the aircraft disassembled in the air. The recovered wreckage of the "YP" was assembled on frames by the RAE. A Comet fuselage was pressurized in a water tank. Intensive research followed, concentrating on the understanding of structural fatigue. The Certificate of Airworthiness was withdrawn 12th April 1954. G-ALYY crashed also into the sea leaving Rome. The second accident was on 8th April 1954.
Flight services was resumed on 23rd March 1954. G-ALYP crashed into the sea leaving Rome. First accident of a De Havilland Comet was on 10th January 1954. The aircraft entered service on 2nd May 1952 (G-ALYP) and put the UK aircraft industry at the forefront of technology. De Havilland were aware of the likelihood of fatigue and had installed several safety measures and tests in line with certification requirements. The pressurised cabin was designed for a cabin pressure equivalent to an altitude of 8000 ft. Key features: 36 passengers, range 2800 km, cruising speed 780 km/h, cruising altitude 35000 ft, aluminium construction, four de Havilland Ghost Jet engines. Design work began on the De Havilland Comet in September 1946.