Green, William and Gordon Swanborough, eds. These improvements were possible largely because of Avon engines with twice the thrust of the Comet 1's Ghosts. [143] The Bruntingthorpe Aerodrome also displays a related Hawker Siddeley Nimrod MR2 aircraft. Cunningham: "[the Comet] flew extremely smoothly and responded to the controls in the best way de Havilland aircraft usually did.". [32] Large picture window views and table seating accommodations for a row of passengers afforded a feeling of comfort and luxury unusual for transportation of the period. [41], The Comet had a total of four hydraulic systems, two primaries, one secondary, and a final emergency system for basic functions such as lowering the undercarriage. Extra payload capacity. [179] Dan-Air bought all of the surviving flyable Comet 4s from the late 1960s into the 1970s; some were for spares reclamation but most were operated on the carrier's inclusive tour charters; a total of 48 Comets of all marks were acquired by the airline. ", "Report of the Public Inquiry into the causes and circumstances of the accident which occurred on the 10 January 1954, to the Comet aircraft G-ALYP, Part IX (d). [83][84] Qantas was interested in the Comet 1 but concluded that a version with more range and better takeoff performance was needed for the London to Canberra route. On January 10, 1954 a Comet broke up in mid-air. [112] The windows' square shape caused stress concentration by generating levels of stress two or three times greater than across the rest of the fuselage. Prins, François. This wreckage was from the starboard side of the cabin just above the three front windows. British South American Airways merged with BOAC in 1949. With the discovery of the structural problems of the early series, all remaining Comets were withdrawn from service, while de Havilland launched a major effort to build a new version that would be both larger and stronger. [1], The Comet is widely regarded as both an adventurous step forward and a supreme tragedy; nevertheless, the aircraft's legacy does include numerous advances in aircraft design and in accident investigations. Il velivolo coinvolto nell'incidente era un De Havilland Comet DH. Built by De Havilland. De Havilland nonetheless began a refit programme to strengthen the fuselage and wing structure, employing thicker gauge skin and replacing the square windows and panels with rounded versions. Il 3 luglio 1970, un de Havilland DH.106 Comet 4 operante su tale rotta si schiantò alle pendici boscose del massiccio del Montseny, vicino ad Arbúcies , in Catalogna, Spagna. When retired in 1973, the airframe was used for foam arrester trials before the fuselage was salvaged at BAE Woodford, to serve as the mock-up for the Nimrod.[168]. Without support from the Ministry of Transport, the proposal languished as a hypothetical aircraft and was never realised. Unlike drill riveting, the imperfect nature of the hole created by punch riveting could cause fatigue cracks to start developing around the rivet. This was because in 1945 no turbojet engine manufacturer in the world was drawing up a design specification for an engine with the thrust and specific fuel consumption, that could power an aircraft at the proposed cruising altitude (40 thousand feet), speed, and transatlantic range as was called for by the Type 106. Flights were temporarily voluntarily suspended, then resumed. Avon-powered Comets were distinguished by larger air intakes and curved tailpipes that reduced the thermal effect on the rear fuselage. The Comet 4 first flew on 27 April 1958 and received its Certificate of Airworthiness on 24 September 1958; the first was delivered to BOAC the next day. [77][78] A slightly longer version of the Comet 1 with more powerful engines, the Comet 2, was being developed,[79] and orders were placed by Air India,[80] British Commonwealth Pacific Airlines,[81] Japan Air Lines,[82] Linea Aeropostal Venezolana,[82] and Panair do Brasil. [63], The Comet 2 had a slightly larger wing, higher fuel capacity and more powerful Rolls-Royce Avon engines, which all improved the aircraft's range and performance;[157] its fuselage was 3 ft 1 in (0.94 m) longer than the Comet 1's. ", "DH106 Comet 'Canopus' 'Fast Taxi Run' - Bruntingthorpe Cold War Jets (May 2018)", "Comet 4C: More Payload on Medium Stages. [64] The square windows of the Comet 1 were replaced by the oval versions used on the Comet 2, which first flew in 1953, and the skin thickness was increased slightly. Pen and Sword, 2013. Second thing within today Comet’s agenda is unluckily a bad record. [23][24] At the controls was de Havilland chief test pilot John "Cats Eyes" Cunningham, a famous night-fighter pilot of the Second World War, along with co-pilot Harold "Tubby" Waters, engineers John Wilson (electrics) and Frank Reynolds (hydraulics), and flight test observer Tony Fairbrother. [100][N 18] BOAC also voluntarily grounded its Comet fleet pending investigation into the causes of the accident. [9] First-phase development of the DH.106 focused on short and intermediate range mailplanes with a small passenger compartment and as few as six seats, before being redefined as a long-range airliner with a capacity of 24 seats. The de Havilland DH.106 Comet was the world's first commercial jet airliner. [76] Popular Mechanics wrote that Britain had a lead of three to five years on the rest of the world in jetliners. On whether we grasp this opportunity and so establish firmly an industry of the utmost strategic and economic importance, our future as a great nation may depend. It was re-assigned to RAE Farnborough as back-up fuselage for water-tank pressure testing, but not used. It was the last leg of the new … [18] From 1947 to 1948, de Havilland conducted an extensive research and development phase, including the use of several stress test rigs at Hatfield Aerodrome for small components and large assemblies alike. [166] Assigned in 1961 to the Blind Landing Experimental Unit (BLEU) at RAE Bedford, the final testbed role played by G–ANLO was in automatic landing system experiments. The span was 115 ft (35.05 m), and overall length 93 ft (28.35 m); the maximum takeoff weight was over 105,000 lb (48,000 kg) and over 40 passengers could be carried. [N 20], In responding to the report de Havilland stated: "Now that the danger of high level fatigue in pressure cabins has been generally appreciated, de Havillands will take adequate measures to deal with this problem. [98][99] With no witnesses to the disaster and only partial radio transmissions as incomplete evidence, no obvious reason for the crash could be deduced. [126][129] The base price of a new Comet 4 was roughly £1.14 million (£22.97 million in 2016). Netaji Subhash Chandra Bose International Airport, "Comet Engineering: The Performance of Airframe, Engines, and Equipment in Operational Service. Era la última parte de un nuevo vuelo de pasajeros entre Londres y Johannesburgo de la British Overseas Airways Corporation (BOAC). 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 remained in commercial service until 1981. The Feb 1959 OAG shows eight transatlantic Comets a week out of London with 10 BOAC Britannias and 11 DC-7Cs. [135] Deliveries to BOAC began on 30 September 1958 with two 48-seat aircraft, which were used to initiate the first scheduled transatlantic services. [194] Since the 2000s, various parties have proposed restoring Canopus, which is maintained by a staff of volunteers,[195] to airworthy, fully flight-capable condition. The second accident was on 8th April 1954. Comet Lost: Services Suspended. [39], Several of the Comet's avionics systems were new to civil aviation. El De Havilland Comet emprendió el vuelo en 1949, pocos años después del final de la Segunda Guerra Mundial. A de Havilland DH-106 Comet 1 passenger plane, registered G-ALYP, was destroyed in an accident 16 km S off Elba, Italy. Ordered by Kuwait Airways, Middle East Airlines, Misrair (later United Arab Airlines), and Sudan Airways, it was the most popular Comet variant. Efficient regional operations. ", GB-High Wycombe: "Dismantlement and relocation of Gate Guardian Comet C2 XK699. [74], In their first year Comets carried 30,000 passengers. A developed engine with slightly less thrust but a longer burn time was known as the Super Sprite, production ceased in October 1960. [130] The Comet 4 enabled BOAC to inaugurate the first regular jet-powered transatlantic services on 4 October 1958 between London and New York (albeit still requiring a fuel stop at Gander International Airport, Newfoundland, on westward North Atlantic crossings). The Comet Story. [82], Nine Comets, including Comet 1s operated by BOAC and Union Aeromaritime de Transport and Comet 4s flown by Aerolíneas Argentinas, Dan-Air, Malaysian Airlines, and United Arab Airlines, were irreparably damaged during takeoff or landing accidents that were survived by all on board. [13] The DH 108s were later modified to test the DH.106's power controls. [49], Diverse geographic destinations and cabin pressurisation alike on the Comet demanded the use of a high proportion of alloys, plastics, and other materials new to civil aviation across the aircraft in order to meet certification requirements. Hall's team began considering fatigue as the most likely cause of both accidents, and initiated further research into measurable strain on the aircraft's skin. In August 1953 BOAC scheduled the nine-stop London to Tokyo flights by Comet for 36 hours, compared to 86 hours and 35 minutes on their Argonaut piston airliner. The other Comet 3 airframe was not completed to production standard and was used primarily for ground-based structural and technology testing during development of the similarly sized Comet 4. On 2 May 1952, as part of BOAC's route-proving trials, G-ALYP took off on the world's first jetliner flight with fare-paying passengers and inaugurated scheduled service from Lond… Oakey, Michael, ed. The DeHavilland Comet Crash. [64] Comet commercial flights would not resume until 1958.[127]. [26] Australian airline Qantas also sent its own technical experts to observe the performance of the prototypes, seeking to quell internal uncertainty about its prospective Comet purchase. The World's First Jet Airliner" U.K. ", "De Havilland Comet 4C G-BDIX Interior View Scottish Museum of Flight. [30], The original Comet was the approximate length of but not as wide as the later Boeing 737-100, and carried fewer people in a significantly more spacious environment. [62] Comet 1s subsequently received more powerful 5,700 lbf (25 kN) Ghost DGT3 series engines. G-ALYP crashed into the sea leaving Rome. The earliest production aircraft designated G-ALYP was loaned to the British Overseas Airways Company and inaugurated the first scheduled overseas flight from London to Johannesburg with fare-paying customers on-board. 25 0 obj <>/Filter/FlateDecode/ID[<9506D2B1A765E2F27D2FF7D425D3B6C8><7D0C510DC53E804094FA71E51B9D00C4>]/Index[10 27]/Info 9 0 R/Length 81/Prev 21416/Root 11 0 R/Size 37/Type/XRef/W[1 2 1]>>stream ", "Metal to Metal Bonding – For Aircraft Structures: Claims of the Redux Process. [171][N 23], The last two Comet 4C aircraft produced were modified as prototypes (XV148 & XV147) to meet a British requirement for a maritime patrol aircraft for the Royal Air Force; initially named "Maritime Comet", the design was designated Type HS 801. [164] The variant added wing pinion tanks, and offered greater capacity and range. "Jet Jubilee (Part 1)". All 21 aboard lost their lives. G-ALYY crashed also into the sea leaving Rome. On 11 March 1943, the Cabinet of the United Kingdom formed the Brabazon Committee, which was tasked with determining the UK's airliner needs after the conclusion of the Second World War. [38] The navigator occupied a dedicated station with a table across from the flight engineer. No apparent fault in the aircraft was found,[N 19] and the British government decided against opening a further public inquiry into the accident. This artificial feel was the first of its kind to be introduced in any aircraft. To achieve optimum efficiency with the new powerplants, the air intakes were enlarged to increase mass air flow. All early Comets were withdrawn from service for accident inquiries, during which orders from British Commonwealth Pacific Airlines, Japan Air Lines, Linea Aeropostal Venezolana, National Airlines, Pan American World Airways, and Panair do Brasil were cancelled. The inquiries into the accidents that plagued the Comet 1 were perhaps some of the most extensive and revolutionary that have ever taken place, establishing precedents in accident investigation; many of the deep-sea salvage and aircraft reconstruction techniques employed have remained in use within the aviation industry. [52], When several of the fuselage alloys were discovered to be vulnerable to weakening via metal fatigue, a detailed routine inspection process was introduced. The cargo hold had its doors located directly underneath the aircraft, so each item of baggage or cargo had to be loaded vertically upwards from the top of the baggage truck, then slid along the hold floor to be stacked inside. 106 Comet 4C con numero di registrazione SU-ALD, numero di serie 6441 e costruito nel 1960. The failure then occurred longitudinally along a fuselage stringer at the widest point of the fuselage (accident report Fig 7). [63], From the Comet 2 onwards, the Ghost engines were replaced by the newer and more powerful 7,000 lbf (31 kN) Rolls-Royce Avon AJ.65 engines. [93], After the loss of G-ALYV, the Central Government of India convened a court of inquiry[92] to examine the cause of the accident. Extensively modified at the factory, the aircraft included a VIP front cabin, a bed, special toilets with gold fittings and was distinguished by a green, gold and white colour scheme with polished wings and lower fuselage that was commissioned from aviation artist John Stroud. Dr P. B. Walker, Head of the Structures Department at the RAE, said he was not surprised by this, noting that the difference was about three to one, and previous experience with metal fatigue suggested a total range of nine to one between experiment and outcome in the field could result in failure. "Duxford's AirSpace opens". [104], During the investigation, the Royal Navy conducted recovery operations. Chief designer Bishop chose the Comet's embedded-engine configuration because it avoided the drag of podded engines and allowed for a smaller fin and rudder, since the hazards of asymmetric thrust were reduced. The 2R ELINT series was operational until 1974, when replaced by the Nimrod R1, the last Comet derivative in RAF service. [97][N 17], Just over a year later, Rome's Ciampino airport, the site of the first Comet hull loss, was the origin of a more disastrous Comet flight. Nine additional Comet 3 airframes were not completed and their construction was abandoned at Hatfield. Smith, Adrian. La BOAC confermò che avrebbe utilizzato velivoli alternativi per ridurre al minimo l'interruzione dei servizi. [42] The undercarriage could also be lowered by a combination of gravity and a hand-pump. The de Havilland DH.106 Comet was the world's first commercial jet airliner. Specialised signals intelligence and electronic surveillance capability was later added to some airframes. It featured an aerodynamically clean design with four de Havilland Ghost turbojet engines buried in the wing roots, a pressurised cabin, and large square windows. Developed and manufactured by de Havilland at its Hatfield Aerodrome in Hertfordshire, United Kingdom, the Comet 1 prototype first flew in 1949. In April 1960, 13 Comets, 19 Britannias and 6 DC-7Cs. The sole surviving Comet fuselage with the original square-shaped windows, part of a Comet 1A registered F-BGNX, has undergone restoration and is on display at the de Havilland Aircraft Museum in Hertfordshire, England. [25], The prototype was registered G-ALVG just before it was publicly displayed at the 1949 Farnborough Airshow prior to the start of flight trials. [111][181] The Royal Canadian Air Force also operated Comet 1As (later retrofitted to 1XB) through its 412 Squadron from 1953 to 1963. [133], The Comet 4 was ordered by two other airlines: Aerolíneas Argentinas took delivery of six Comet 4s from 1959 to 1960, using them between Buenos Aires and Santiago, New York and Europe, while East African Airways received three new Comet 4s from 1960 to 1962 and operated them to the United Kingdom and to Kenya, Tanzania, and Uganda. De Havilland Aircraft Company Limited va ser un fabricant d'avions britànic establert a finals de la década de 1920 per Geoffrey de Havilland al aeròdrom d'Stag Lane als afores de Londres.Posteriorment es va traslladar a Hatfield, Hertfordshire. The Comet design was finalized in 1945, as the British aircraft industry was attempting to establish a commercial aircraft industry post-World War II. [50] At its introduction, Comet airframes would be subjected to an intense, high-speed operating schedule which included simultaneous extreme heat from desert airfields and frosty cold from the kerosene-filled fuel tanks, still cold from cruising at high altitude. [10] A number of unorthodox configurations were considered, ranging from canard to tailless designs;[N 4] All were rejected. However, within a year of entering airline service, problems started to emerge, with three Comets lost within twelve months in highly publicised accidents, after suffering catastrophic in-flight break-ups. [53], Operationally, the design of the cargo holds led to considerable difficulty for the ground crew, especially baggage handlers at the airports. Proctor, Jon, Mike Machat and Craig Kodera. They ran smoothly and were less noisy than piston engines, had low maintenance costs, and were fuel-efficient above 30,000 ft (9,100 m). For the 1930s racing aircraft, see, "During the next few years, the UK has an opportunity, which may not recur, of developing aircraft manufacture as one of our main export industries. [152] In response to the Comet tragedies, manufacturers also developed various means of pressurisation testing, often going so far as to explore rapid depressurisation; subsequent fuselage skins were of a greater thickness than the skin of the Comet.