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BEA's Comets got a welcome response from crews and passengers but they were not so well received by the baggage handlers. This was because the baggage/cargo holds had dorsal doors accessed directly underneath the plane so that each item of baggage or cargo had to be loaded upwards from the top of the cab of the baggage truck, through the little hole and then slid along the hold floor to be stacked inside. They had to be retrieved as slowly and effortfully on arrival.
BEA's Comets got a welcome response from crews and passengers but they were not so well received by the baggage handlers. This was because the baggage/cargo holds had dorsal doors accessed directly underneath the plane so that each item of baggage or cargo had to be loaded upwards from the top of the cab of the baggage truck, through the little hole and then slid along the hold floor to be stacked inside. They had to be retrieved as slowly and effortfully on arrival.
[[United States of America|American]] operator [[Capital Airlines]] ordered four Comet 4s and 4As in July 1956. The '''Comet 4A''' was designed for short-range operations and had a stretched fuselage with short wings (lacking the pinion (outboard wing) fuel tanks of the Comet 4). This order was cancelled but the aircraft were built for [[British European Airways]] (BEA) as the '''Comet 4B''', with a further fuselage stretch of 38 in (97 cm) and seating for 99 passengers. The first Comet 4B (G-APMA) flew on 27 June 1959 and BEA aircraft G-APMB began Tel Aviv to London-Heathrow service on 1 April 1960.
[[United States of America|American]] operator [[Capital Airlines]] ordered four Comet 4s and 4As in July 1956. The '''Comet 4A''' was designed for short-range operations and had a stretched fuselage with short wings (lacking the pinion (outboard wing) fuel tanks of the Comet 4). This order was cancelled but the aircraft were built for [[British European Airways]] (BEA) as the '''Comet 4B''', with a further fuselage stretch of 38 in (97 cm) and seating for 99 passengers. The first Comet 4B (G-APMA) flew on 27 June 1959 and BEA aircraft G-APMB began Tel Aviv to London-Heathrow service on 1 April 1960.
[[Image:Comet_4C_Cockpit.jpg|400px|thumb|right|DeHavilland Comet 4C [[cockpit]]]]
[[Image:Comet_4C_Cockpit.jpg|400px|thumb|left|DeHavilland Comet 4C [[cockpit]]]]
The last Comet 4 variant was the '''Comet 4C''' with the same longer fuselage as the Comet 4B coupled with the longer wings and extra fuel tanks of the original Comet 4, which gave it a longer range than the 4B. The first Comet 4C flew on 31 October 1959 and [[Mexicana de Aviacion|Mexicana]] began scheduled Comet 4C flights in 1960. The last two Comet 4C fuselages were used to build prototypes of the Hawker Siddeley Nimrod maritime patrol aircraft.
The last Comet 4 variant was the '''Comet 4C''' with the same longer fuselage as the Comet 4B coupled with the longer wings and extra fuel tanks of the original Comet 4, which gave it a longer range than the 4B. The first Comet 4C flew on 31 October 1959 and [[Mexicana de Aviacion|Mexicana]] began scheduled Comet 4C flights in 1960. The last two Comet 4C fuselages were used to build prototypes of the Hawker Siddeley Nimrod maritime patrol aircraft.


Revision as of 23:58, 31 October 2010

This article is about the jet airliner. For the 1930s racing aircraft, see de Havilland DH.88.


DH.106 Comet
Comet 3 G-ANLO in BOAC-style markings at Farnborough in September 1954
Role Airliner
Manufacturer de Havilland
First flight 27 July 1949
Introduction 2 May 1952 with BOAC
Status In military service only
Primary users BOAC
See Operators
Number built 114 (including prototypes)[1][2]
Variants Hawker Siddeley Nimrod

The de Havilland Comet was the world's first commercial jet airliner to reach production.[N 1] Developed and manufactured by de Havilland, it first flew in 1949 and was considered a landmark in British aeronautical design. After introduction into commercial service, the initial Comet versions suffered from catastrophic metal fatigue, causing two well-publicised accidents.

The Comet had to be withdrawn and was redesigned. The Comet 4 series subsequently enjoyed a long and productive career of over 30 years, although sales never fully recovered. A specialised reconnaissance variant of the Hawker Siddeley Nimrod, the military derivative of the Comet airliner, are still in service and are expected to be retired in March 2011 over sixty years after the Comet's first flight.

Development

During the Second World War, the Brabazon Committee studied Britain's postwar airliner needs.[3] Fighting scepticism that jet engines were too fuel-hungry and unreliable,[3] Sir Geoffrey de Havilland, head of the de Havilland company, was a committee member and used his influence and the company's expertise with jets to include mention of the need for a transatlantic jet mailplane. The committee accepted the proposal, calling it the "Type IV" (of five designs), and awarded the production contract to de Havilland's DH.106.[4] Out of all the Brabazon designs, the Comet was seen as the riskiest,[3] however, British Overseas Airways Corporation (BOAC) found the Type IV's specifications attractive and in December 1945, agreed to buy 10 aircraft.

Design work began in 1946 under Ronald Bishop, who had been responsible for the de Havilland Mosquito fighter-bomber. Several configurations were considered, including twin booms and a swept-wing, tailless design, for which the experimental DH 108 was ordered to test the configuration, but a more conventional design was eventually chosen and announced as the Comet in December 1947. First deliveries were expected by 1952.

The first flight of a prototype DH.106 Comet took place on 27 July 1949, and lasted 31 minutes.[5] The pilot was de Havilland Chief Test Pilot John Cunningham, a famous wartime night-fighter pilot, who later commented: "I assumed that it would change aviation, and so it has proved. It was a bit like Concorde."[6] Also on board were co-pilot John Wilson and flight test observer Tony Fairbrother. Fairbrother commented that: "The world changed as our wheels left the ground."[7] He went on to manage the development and testing of the Comet 2, 3, 4, 4B and 4C.

The aircraft was publicly displayed at the 1949 Farnborough Airshow before beginning flight trials. A year later, the second prototype made its maiden flight. On 2 April 1951, this aircraft was delivered to the BOAC Comet Unit at Hurn under the registration G-ALZK and carried out 500 flying hours of crew training and route proving.

The British Government considered the development of the Comet a highly ideological matter, as high-ranking officials perceived the need to meet foreign competition and surpass them when there was the opportunity to do so:

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. 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.

— Duncan Sandys, Minister of Supply, 1952.[8]

Design

The Comet is an all-metal low-wing cantilever monoplane powered by four jet engines, approximately the length of a Boeing 737 but carrying fewer people in greater comfort. The earliest Comets had 11 rows of seats with four seats to a row in the 1A configuration used by Air France; BOAC used an even roomier arrangement of 36 seats.[9] The galley could serve hot and cold food and drinks and there was a bar. Other amenities included separate men's and women's washrooms.[10] The cabin was quieter than those of propeller-driven airliners.[11] The Comet's four-man cockpit held two pilots, a flight engineer, and a navigator.[12]

The clean, low-drag design featured many unique or innovative design elements, including a swept leading edge, integral wing fuel tanks and four-wheel bogie main undercarriage units designed by de Havilland.[12] For emergencies, life rafts were stored in the wings near the engines and a life vest was stowed under each seat bottom.[12]

The air intakes of preserved Comet 4C at Imperial War Museum Duxford.
Olympic Airways Comet 4B at Manchester in 1966, showing engines buried in wing and revised round windows of all Comet 4s.

Two pairs of de Havilland Ghost 50 Mk1 turbojet engines were buried in the wings close to the fuselage.[13] British designers chose this configuration because it avoided the drag of podded engines and allowed a smaller fin and rudder, since the hazards of asymmetric thrust were reduced.[14] The engines' higher mounting in the wings also reduced the risk of ingestion damage, a major problem for turbine engines. These benefits were compromised by increased structural weight and general complexity, including armour for the engine cells (in case of an engine explosion) and a more complicated wing structure.[15] This arrangement also carried higher risk of catastrophic wing failure in case of an engine fire, cited as the main reason the Boeing Aircraft Company chose podded engines in their subsequent jet bomber and airliner designs.

The Comet was originally intended to have two hydrogen peroxide powered de Havilland Sprite booster rockets for takeoff under hot and high conditions from airports such as Khartoum and Nairobi.[16][9] These were tested on 30 flights, but the Ghosts were apparently powerful enough without them. The later Comet 4 was highly rated for its takeoff performance from high altitude locations such as Mexico City. Newer AJ.65 Avon engines replaced the Ghosts upon the Comet 2.[17] High engine performance combined with a low weight (compared to the Boeing 707 and Douglas DC-8), and exceptionally clean design all contributed to its high performance. Early-model Comets required about five or six man-hours of maintenance labour per flight hour, fewer than the propeller-driven aircraft it replaced.

The Comet's thin metal skin was composed of advanced new alloys (Directorate of Technical Development 564/L.73 and DTD 746C/L90) and was both chemically bonded using the adhesive Redux and riveted, which saved weight and reduced the risk of fatigue cracks spreading from the rivets. When it went into service with BOAC on 2 May 1952, the Comet was the most exhaustively tested airliner in history. For example, a water tank was used to test the entire forward fuselage section for metal fatigue by repeatedly pressurising to 2.75 psi overpressure (11 psi = 76 kPa) and depressurising through more than 16,000 cycles, equivalent to about 40,000 hours of airline service.[18] The windows were tested under a pressure of 12 psi (83 kPa), 4.75 psi above the normal service ceiling of 36,000 ft (10,973 m).[18] One window frame survived a massive 100 psi (690 kPa), about 1,250% over the maximum pressure it would encounter in service.[18]

Operational history

Introduction

The first production aircraft (G-ALYP) flew in January 1951. On 22 January 1952, G-ALYS was the first Comet to receive a certificate of airworthiness. On 2 May, G-ALYP took off on the world's first all-jet flight with fare-paying passengers, beginning scheduled service to Johannesburg.[19][20] The last plane from the initial order (G-ALYZ) began flying in September 1952, carrying freight along South American routes while simulating passenger schedules.

The Comet was a hit with passengers and commercial success was widely expected. Queen Elizabeth the Queen Mother was an early passenger on a special flight, becoming the first member of the British Royal Family to fly by jet. The Comet flew about 50% faster than advanced piston-engined types like the Douglas DC-6 (490 mph for the Comet compared to 315 mph for the DC-6B), and its rate of climb was also far higher, which could cut flight times in half. The Ghost engine was smooth, relatively simple, fuel-efficient above 30,000 ft (9,144 m), [N 2] had low maintenance costs, little vibration, and enabled operations above weather the competition had to fly through. 30,000 passengers were carried during the first year of service and over 50 Comets were ordered.

At their height there were four weekly cycles for the BOAC Comet 1 fleet:

  1. 22.00 Sun London - Singapore (06.30 Tue)/12.30 Tue Singapore - London (11.40 Wed)/14.00 Wed London - Colombo (14.45 Thur)/13.30 Fri Colombo - London (08.00 Sat)
  2. 18.00 Fri London - Tokyo (13.30 Mon)/22.30 Tue Tokyo - London (07.40 Thurs)
  3. 16.00 Sun London - Johannesburg (14.40 Mon)/10.00 Tues Johannesburg - London (07.05 Wed)/ 16.00 Wed London - Johannesburg (14.40 Thur)/10.00 Fri Johannesburg - London (07.05 Sat)
  4. 16.00 Tues London - Johannesburg (14.40 Wed)/10.00 Thur Johannesburg - London (07.05 Fri)/ 16.00 Fri London - Johannesburg (14.40 Sat)/10.00 Sun Johannesburg - London (07.05 Mon)

Based on full occupancy (36 seats per aircraft), the income for each cycle per week was: 1. £29,664, 2. £20,592, 3. £26,640, 4. £26,640 Total for week: £103,536/ Year: £5,383,872.

Early accidents and incidents

DH.106 Comet 1 of BOAC at London Heathrow on 2 June 1953.

On 26 October 1952, a BOAC flight departing from Ciampino airport near Rome failed to become airborne and ran into rough ground at the end of the runway. Two passengers sustained only minor injuries, but the aircraft was a total loss. The following March, a new Canadian Pacific Airlines Comet 1A (CF-CUN),[N 3] known as "Empress of Hawaii," being delivered to Australia, also failed to become airborne on takeoff from Karachi, Pakistan. The aircraft plunged into a dry drainage canal and collided with an embankment, killing all five crew and six passengers on board, the first-ever fatal crash of a passenger jet airliner.[21]

Both of these accidents were originally attributed to pilot error: over-rotation had led to a loss of lift from the leading edge of the plane's wing. It was later determined that the wing profile led to a loss of lift at high angle of attack, and the engine inlets suffered from a lack of pressure recovery in these conditions as well. The wing leading edge was re-profiled, and a wing fence was added to control spanwise flow. A fictionalised investigation into these takeoff accidents is a subject of the 1959 novel Cone of Silence by David Beaty, a former BOAC captain. Cone of Silence was made into a film in 1960, and Beaty also recounted the story of the Comet's takeoff accidents in a chapter of his 1984 non-fiction work Strange Encounters: Mysteries of the Air.

A preserved Comet 4C painted in BOAC livery.

The next fatal accident involving passengers was on 2 May 1953, when a BOAC Comet 1 (G-ALYV) crashed in a severe tropical storm six minutes after taking off from Calcutta/Dum Dum (now Netaji Subhash Chandra Bose International Airport), India,[22] killing all 43 on board. The crash was attributed to structural failure of the airframe. The break-up began with a stabiliser and may have been exacerbated by over-manipulation of the fully powered flight controls. The Comet 1 and 1A have been criticised for a lack of "feel" in their controls,[23] though test pilot John Cunningham contended that "it flew extremely smoothly and responded to the controls in the best way de Havilland aircraft usually did".[6]

Comet disasters of 1954

Main articles: BOAC Flight 781 and South African Airways Flight 201

Rome's Ciampino airport, the site of the first Comet hull loss, was again the origin of more disastrous Comet flights just over a year later. On 10 January 1954, 20 minutes after taking off from Ciampino, Comet G-ALYP ("Yoke Peter"), BOAC Flight 781, broke up in flight and crashed into the Mediterranean off the Italian island of Elba, with the loss of all 35 on board.[24] There was no obvious reason for the crash, and the fleet was grounded while the Abell Committee met to determine potential causes of the crash. The committee focused on six potential problems: control flutter (which had led to the loss of the de Havilland Swallow), structural failure due to high loads or metal fatigue of the wing structure, failure of the powered flight controls, failure of the window panels leading to explosive decompression, or fire and other engine problems. The committee concluded fire was the most likely cause of the problem, and a number of changes were made to the aircraft to protect the engines and wings from damage which might lead to another fire.[25]

During this investigation, the Royal Navy conducted recovery operations. The first wreckage was discovered on 12 January and the search continued until August, by which time 70 % of the main structure, 80 % of the power section, and 50 % of the equipment had been recovered. The forensic reconstruction effort was only lately underway when the Abell Committee reported their findings. On 4 April, Lord Brabazon wrote to the Minister of Transport, "Although no definite reason for the accident has been established, modifications are being embodied to cover every possibility that imagination has suggested as a likely cause of the disaster. When these modifications are completed and have been satisfactorily flight tested, the Board sees no reason why passenger services should not be resumed." Comet flights resumed on 23 March 1954.

Then on 8 April 1954, Comet G-ALYY ("Yoke Yoke"), on charter to South African Airways, was on a leg from Rome to Cairo (of a longer flight from London to Johannesburg), when it crashed in the waters near Naples.[24] The fleet was immediately grounded once again and a large investigation board was formed under the direction of the Royal Aircraft Establishment (RAE).[24] Winston Churchill tasked the Royal Navy with helping to locate and retrieve the wreckage so that the cause of the accident could be found.

Engineers subjected an identical airframe, G-ALYU, to repeated re-pressurisation and over-pressurisation and after 3,057 flight cycles (1,221 actual and 1,836 simulated), G-ALYU failed due to metal fatigue near the front port-side escape hatch.[26] Investigators began considering fatigue as the most likely cause of both accidents and initiated further research into measurable strain on the skin.[24] Stress around the window corners was found to be much higher than expected, and stresses on the skin were generally more than previously expected or tested.[27] This was due to stress concentration, a consequence of the windows' square shape, the levels of stress at these corners could be two or three times that across the rest of the fuselage.[28]

The problem was exacerbated by the punch rivet construction technique employed.[24] The windows had been engineered to be glued and riveted, but had been punch riveted only. Unlike drill riveting, the imperfect nature of the hole created by punch riveting may cause the start of fatigue cracks around the rivet.

The principal investigator concluded, "In the light of known properties of the aluminium alloy D.T.D. 546 or 746 of which the skin was made and in accordance with the advice I received from my Assessors, I accept the conclusion of RAE that this is a sufficient explanation of the failure of the cabin skin of Yoke Uncle by fatigue after a small number, namely, 3,060 cycles of pressurisation."[29]

Before the Elba accident, G-ALYP had made 1,290 pressurised flights and at the time of the Naples accident G-ALYY had made 900 pressurised flights. Walker said he was not surprised by this, noting that the difference was about 3 to 1 and previous experience with metal fatigue suggested a total range of 9 to 1 between experiment and outcome in the field could result in failure. Thus, if the tank test result was "typical", aircraft failures could be expected at anywhere from 1000 to 9000 cycles. By then, the RAE had reconstructed about ⅔ of G-ALYP at Farnborough and found fatigue crack growth from a rivet hole at the low-drag fiberglass forward "window" around the Automatic Direction Finder, which had caused a catastrophic breakup of the aircraft in high altitude flight.

The square windows of the Comet 1 were redesigned as oval for the Comet 2, which first flew in 1953. The skin sheeting was thickened slightly. The remaining Comet 1s and 1As were either scrapped or modified with oval window rip-stop doublers (a thick, structurally strong ring of material that prevents a crack from spreading further) and a program to produce a Comet 2 with more powerful Avons was delayed. All production Comet 2s were modified to alleviate the fatigue problems and most of these served with the RAF as the Comet C2. The Comet did not resume commercial airline service until 1958, when the much-improved Comet 4 was introduced and became the first jet airliner to enter transatlantic service. The Comet nose section was also used on the Sud Aviation Caravelle. As is often the case in aeronautical engineering, other aircraft manufacturers learned from and profited by de Havilland's hard-learned lessons.[30][8] According to John Cunningham, representatives from American manufacturers such as Boeing and Douglas "admitted that if it hadn't been for our problems, it would have happened to one of them".[6]

Resumption of service

Dan-Air London Comet 4 G-APDB preserved at Duxford, July 1985

Following the structural problems, all remaining Comets were withdrawn from service, with de Havilland launching a major effort to build a new version that would be both larger and stronger. This one, the Comet 4, enabled de Havilland to return to the skies in 1958; the new model of the Comet allowed the first regular jet-powered transatlantic services to begin that same year.[31] However by then, the United States had its Boeing 707 jetliner along with the Douglas DC-8, both of which were larger and more efficient to operate.[32]

Orders for the Comet dried up, with the last one delivered in 1964. A total of 76 Comet 4 family aircraft were delivered from 1958 to 1964. BOAC retired its Comet 4s from revenue service in 1965 but other operators continued flying Comets in commercial passenger service until 1981. Dan-Air played a significant role in the fleet's later history and at one time owned all 49 remaining airworthy civil Comets. In 1997, a Comet 4C which had been owned by the British government made the last documented Comet flight.

Variants

Comet 1

The square-windowed Comet 1 was the first model produced. An updated Comet 1A was offered with higher allowed weight and water-methanol injection; in the wake of the 1954 disasters, some of these were modified as Comet 1XBs with strengthened fuselages and oval windows. A bomber variant was proposed in May 1948 to Air Ministry specification B35/46 as the DH.111, but this was never developed further.[citation needed]

Comet 2

Comet C.2 XK715 of No. 216 Squadron Royal Air Force at Filton Bristol in 1964.

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. Following the Comet 1 disasters, these models were rebuilt with heavier gauge skin and rounded openings. 12 of the 44-seat Comet 2s were ordered by BOAC for the South Atlantic route.[33] The first production aircraft (G-AMXA) flew on 27 August 1953.[34] Although these aircraft performed well on the South Atlantic routes, their range was still not suitable for the North Atlantic. All but four Comet 2s were allocated to the RAF. Eight Comet C2 transport aircraft and two Comet T2 crew trainers were delivered to the RAF beginning in 1955.

  • Comet 2X: Limited to a single Comet Mk 1 powered by four Rolls-Royce Avon 502 turbojet engines and used as a development aircraft for the Comet 2.
  • Comet 2E: Two Comet 2 airliners were fitted with Avon 504s in the inner nacelles and Avon 524s in the outer ones. These aircraft were used by BOAC for proving flights during 1957–1958.

Comet 3

The Comet 3 was a lengthened Comet 2 with greater capacity and range, which flew for the first time on 19 July 1954.[35] It was demonstrated at the Farnborough SBAC Show in September. After the fatigue accidents, orders dwindled and only two Comet 3s were constructed. G-ANLO was the only flying Comet 3, and took part in a marathon round-the-world promotional tour in December 1955, flown by John Cunningham.[35] It was modified with reduced span wings as the Comet 3B and was displayed at Farnborough in September 1958. The other Comet 3 was used for structural and technology testing during development of the similarly sized Comet 4. Nine further airframes were not completed and their construction was abandoned at Hatfield.

Comet 4

DeHavilland Comet 4 flight deck

The Comet 4 was a further improvement on the stretched Comet 3 with even greater fuel capacity. This design had come a long way from the original Comet 1. The aircraft had grown by 18 ft 6 in (5.64 m) and typically seated 74 to 81 passengers compared to the Comet 1's 36 to 44. It had a longer range, higher cruising speed, and higher maximum takeoff weight. These improvements were possible largely because of Avons with twice the thrust of the Comet 1's Ghosts.

BOAC ordered 19 Comet 4s in March 1955 and a Comet 4 (G-APDA) first flew on 27 April 1958. Deliveries to BOAC began on 30 September 1958 with two aircraft. BOAC's G-APDC initiated the first transatlantic Comet 4 service and the first scheduled transatlantic passenger jet service in history, flying from London to New York with a stopover at Gander on 4 October 1958. Rival Pan Am's inaugural 707 service began three weeks later.

British Airtours Comet 4B at Manchester Airport, July 1970.

BEA's Comets got a welcome response from crews and passengers but they were not so well received by the baggage handlers. This was because the baggage/cargo holds had dorsal doors accessed directly underneath the plane so that each item of baggage or cargo had to be loaded upwards from the top of the cab of the baggage truck, through the little hole and then slid along the hold floor to be stacked inside. They had to be retrieved as slowly and effortfully on arrival. American operator Capital Airlines ordered four Comet 4s and 4As in July 1956. The Comet 4A was designed for short-range operations and had a stretched fuselage with short wings (lacking the pinion (outboard wing) fuel tanks of the Comet 4). This order was cancelled but the aircraft were built for British European Airways (BEA) as the Comet 4B, with a further fuselage stretch of 38 in (97 cm) and seating for 99 passengers. The first Comet 4B (G-APMA) flew on 27 June 1959 and BEA aircraft G-APMB began Tel Aviv to London-Heathrow service on 1 April 1960.

DeHavilland Comet 4C cockpit

The last Comet 4 variant was the Comet 4C with the same longer fuselage as the Comet 4B coupled with the longer wings and extra fuel tanks of the original Comet 4, which gave it a longer range than the 4B. The first Comet 4C flew on 31 October 1959 and Mexicana began scheduled Comet 4C flights in 1960. The last two Comet 4C fuselages were used to build prototypes of the Hawker Siddeley Nimrod maritime patrol aircraft.

Comet 5 design

The Comet 5 was proposed as an improvement over previous models, including a wider fuselage with five-abreast seating, a wing with greater sweep and podded Rolls-Royce Conway engines. Without support from the Ministry of Transport, none were ever built. The MoT subsequently backed BOAC's order of Conway-powered Boeing 707s.

Hawker Siddeley Nimrod

Main article: Hawker Siddeley Nimrod

The last two Comet 4 fuselages produced were modified as prototypes to meet a British requirement for a maritime patrol aircraft for the Royal Air Force, designated HS.801.[36] This became the Hawker Siddeley Nimrod and was built at the Hawker Siddeley factory at Woodford Aerodrome. Entering service in 1969, five Nimrod variants have been produced,[37] with two still in service. While the highly modified Nimrod MRA 4 was originally scheduled to enter service in 2003, however, following almost a decade of delays and overruns the project was cancelled in the Strategic Defence and Security Review in October 2010.[38]

Production summary

The Comet was built at two different de Havilland factories: Hatfield and Hawarden. A total of 114 aircraft were completed and flown: 12 Comet 1s, 10 Comet 1As, 15 Comet 2s, one Comet 3, 74 Comet 4, and two HS.801s.

Thirteen aircraft were lost in fatal accidents and of these, five were considered to have been brought about by aircraft design or fatigue problems. Twenty-four airlines flew the Comet and it remained in passenger service for almost three decades, until 1981. Designed over 50 years earlier at the beginning of the jet age, a variant of the Comet, the Nimrod, flying with modern avionics, is still in service with the Royal Air Force.

Aircraft on display

Comet 1
  • The only complete surviving Comet 1 is a Comet 1XB on display at the RAF Museum Cosford, painted in BOAC colours with the registration G-APAS[39], although it never flew for that airline, having been delivered to Air France and then to the Ministry of Supply after conversion to 1XB standard.
  • Mk 1A F-BGNX, the fuselage of which is preserved at the de Havilland Aircraft Heritage Centre in Hertfordshire, is the only surviving fuselage displaying the original 'square' windows. The aircraft is currently under restoration.
Comet 2
  • Comet C2 "Sagittarius" serial XK699, later maintenance serial 7971M) is displayed at the gate of RAF Lyneham in Wiltshire. Lyneham was previously the operational base for all RAF operated Comets.
Comet 4C Canopus at the British Aviation Heritage Centre, Bruntingthorpe Aerodrome.
Comet 4
  • Comet 4B (Registration G-APYD) is stored at the Science Museum facility at Wroughton, Wiltshire.
  • Comet 4C (Registration N888WA) is being restored and on display in BOAC livery at the restoration facility of the Museum of Flight at Paine Field next to Boeing's Everett, WA widebody plant. It is being restored to its original Mexicana livery and interior.
  • Comet 4C (Registration N777WA) is on display at the Parque Zoológico Irapuato in Mexico.
  • Comet 4 (Registration G-APDB) is on display at the Imperial War Museum Duxford, England. Long displayed outdoors in Dan-Air colours as part of the Flight Line Display it is now in BOAC livery in the new AirSpace building.[40]
  • Comet 4C (Registration G-BDIW) is on display at the Flugausstellung Leo Junior at Hermeskeil, Germany in Dan-Air colours.
  • Comet 4C (Registration G-BDIX) is on display at the National Museum of Flight at East Fortune near Edinburgh, Scotland in Dan-Air livery.
  • Comet 4C (Registration SU-ALM and later G-BEEX) on display at the North East Aircraft Museum, Sunderland, United Kingdom - Cockpit Section only.
  • The last Comet to fly was Canopus (Serial XS235), which is kept in running condition at Bruntingthorpe Aerodrome, where she regularly conducts fast taxi runs.

Operators

Civilian operators

 Argentina
 Canada
 Sri Lanka (Ceylon)
East African Community (Kenya, Tanzania, Uganda)
 Ecuador
  • AREA
 Egypt
 France
 Greece
 Guatemala
 Hong Kong
 Kuwait
 Lebanon
 Malaysia
 Malaysia /  Singapore
 Mexico
 Saudi Arabia
 South Africa
 Sudan
 United Kingdom

Military operators

 Canada
 United Kingdom

Cancelled orders

 Brazil
 Japan
 United States
 Venezuela

Accidents and incidents

  • 26 October 1952: Comet 1 G-ALYZ of BOAC crashed on takeoff from Rome-Ciampino Airport, Italy.[41]
  • 3 March 1953: Comet 1 CF-CUN of Canadian Pacific Airlines stalled on takeoff at Karachi, Pakistan.[41]
  • 2 May 1953: Comet 1 G-ALYV of BOAC crashed at Calcutta, India.[41]
  • 25 June 1953: Comet 1 F-BGSC of Union Aeromaritime de Transport skidded off a runway at Dakar, Senegal, damaged beyond repair.[41]
  • 10 January 1954: Comet 1 G-ALYP of BOAC, operating Flight 781, crashed into the sea south of Elba, Italy.[41]
  • 27 August 1959: Comet 4 LV-AHP of Aerolíneas Argentinas flew into a mountain on approach to Asunción, Paraguay.[41]
  • 20 February 1960: Comet 4 LV-AHO of Aerolíneas Argentinas damaged beyond repair in a heavy landing at Buenos Aries-Ezeiza, Argentina.[41]
  • 23 November 1961: Comet 4 LV-AHR of Aerolíneas Argentinas, operating Flight 322 hit a tree on takeoff at São Paulo, Brazil.[41]
  • 21 December 1961: Comet 4 G-ARJM of British European Airways crashed on takeoff from Ankara, Turkey.[41]
  • 19 July 1962: Comet 4 SU-AMW of United Arab Airlines crashed into a mountain 100 km north-east of Bangkok, Thailand.[41]
  • 20 March 1963: Comet 4C SA-R-7 of the Saudi Arabian government crashed in the Italian Alps near Cuneo.[41]
  • 28 July 1963: Comet 4 SU-ALD of United Arab Airlines Flight 896 crashed into the sea near Bombay, India.[41]
  • 22 March 1964: Comet 4 G-APDK on lease to Malaysian Airlines damaged beyond repair landing at Singapore.[41]
  • 28 December 1968: Comet 4Cs OD-ADQ and OD-ADR of Middle East Airlines both destroyed by Israeli troops in an attack at Beirut, Lebanon.[41]
  • 14 January 1970: Comet 4 SU-ANI of United Arab Airlines crashed at Addis Ababa, Ethiopia.[41]
  • 9 February 1970: Comet 4 SU-ALE of United Arab Airlines crashed after takeoff near Munich, West Germany.[41]
  • 3 July 1970: Comet 4 G-APDN of Dan-Air flew into the Monteseny mountains, north-west of Barcelona, Spain.[41]
  • 7 October 1970: Comet 4 G-APDL of Dan-Air damaged beyond repair after a wheels up landing at Newcastle Airport, England.[41]
  • 2 January 1971: Comet 4 SU-ALC of United Arab Airlines Flight 844 crashed near Tripoli Airport, Libya.[41]

Specifications (Comet 4)

Data from Jane's All The World's Aircraft 1965–66[43]

General characteristics

Performance

See also

Related development

Aircraft of comparable role, configuration, and era

Related lists

References

Notes
  1. ^ The Avro Tudor and Vickers VC.1 Viking, fitted with Rolls-Royce Nene turbojets, had flown earlier but were experimental models.
  2. ^ Depending on weight and temperature, cruise fuel consumption was 6 to 10 kg per nautical mile, the higher figure being at the lower altitude needed at high weight.
  3. ^ The Comet was bought in preference to the Canadian-built Avro Canada Jetliner, another pioneering jet airliner.
Citations
  1. ^ Lo Bao 1996, pp. 36–47.
  2. ^ Walker 2000, pp. 185–190.
  3. ^ a b c Trischler and Helmuth 2003, p. 88.
  4. ^ Jackson 1988.
  5. ^ Green and Swanborough April 1977, p. 174.
  6. ^ a b c Faith 1996, pp. 158–165.
  7. ^ "Obituary: Tony Fairbrother." The Times, 26 January 2005.
  8. ^ a b Trischler and Helmuth 2003, p. 90.
  9. ^ a b Cookman, Aubery O. Jr. "Commute by Jet." Popular Mechanics, 93(4), April 1950, pp. 149–152.
  10. ^ Francis 1950, p. 98.
  11. ^ Francis 1950, p. 100.
  12. ^ a b c Francis 1950, p. 99.
  13. ^ Francis 1950, pp. 100–101.
  14. ^ Francis 1950, pp. 101–102.
  15. ^ Francis 1950, p. 103.
  16. ^ Francis 1950, pp. 98–102.
  17. ^ "Comet Gets Stronger Engines." Popular Science, 160(6), June 1952, p. 142.
  18. ^ a b c Davies and Birtles 1999, p. 30.
  19. ^ McNeil 2002, p. 39.
  20. ^ "On This Day: Comet inaugurates the jet age." BBC News, 2 May 1952.
  21. ^ "Accident Record." Aviation Safety Network. Retrieved: 22 September 2010.
  22. ^ Darling 2005, p. 36.
  23. ^ Job 1996, p. 14.
  24. ^ a b c d e Withey, P. A. "Fatigue Failure of the de Havilland Comet I." Engineering Failure Analysis, 4(2), June 1997, pp. 147–154.
  25. ^ "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)." geocities.com. Retrieved: 3 September 2010.
  26. ^ "Comet." RAF Museum. Retrieved: 3 September 2010.
  27. ^ Atkinson et al. 1962, p. 9.
  28. ^ Atkinson et al. 1962, pp. 4, 6, 27.
  29. ^ "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 XI (a. 69)." geocities.com. Retrieved: 3 September 2010.
  30. ^ Job 1996, p. 21.
  31. ^ McNeil 2002, p. 39.
  32. ^ Haddon-Cave 2009, p. 16.
  33. ^ "Comet Service To South America Planned" (News). The Times, Saturday, Issue 52516, 10 January 1953, col G, p. 3.
  34. ^ Jackson 1987, p. 456.
  35. ^ a b Jackson 1987, p. 457.
  36. ^ Haddon-Cave 2009, p. 17.
  37. ^ Haddon-Cave 2009, p. 19.
  38. ^ "Defence review: Cameron unveils armed forces cuts." BBC News, 21 October 2010.
  39. ^ "G-INFO Database". Civil Aviation Authority.
  40. ^ Oakey, Michael, ed. "Duxford's AirSpace opens". Aeroplane Vol. 35 No. 9, September 2007.
  41. ^ a b c d e f g h i j k l m n o p q r s t u v Roach and Eastwood 1992, pp. 331–335.
  42. ^ Silversmith, Jol A. "The Legacy of Douglas Corrigan: 'Wrong Way' Landings By Commercial Airliners." Third Amendment, December 2009. Retrieved: 3 September 2010.
  43. ^ Taylor 1965, pp. 153–154.
  44. ^ Flight 28 March 1958, pp. 422–423.
  45. ^ Jackson 1987, p. 464.
Bibliography
  • Atkinson, R. J., W. J. Winkworth and G. M. Norris. "Behaviour of Skin Fatigue Cracks at the Corners of Windows in a Comet I Fuselage." Ministry of Aviation, via Her Majesty's Stationery Office, 1962.
  • Avrane, A. Sud Est Caravelle. London: Jane's Publishing, 1981. ISBN 0-7106-0044-5.
  • "Comet Resurgent:A decade of D.H. Jet Transport Design". Flight, 28 March 1958, pp. 420–425.
  • Davies, R.E.G. and Philip J. Birtles. Comet: The World's First Jet Airliner. McLean, Virginia: Paladwr Press, 1999. ISBN 1-888962-14-3.
  • Faith, Nicholas. Black Box. London: Boxtree, 1996. ISBN 0-7522-2118-3.
  • Francis, Decon. "I Saw This Jet Liner Fly 500 m.p.h." Popular Science, 156(5), May 1950, pp. 98–104.
  • Green, William and Gordon Swanborough, eds. "Jet Jubilee (Part 1)". Air International, Vol. 12, No. 3, March 1977, pp. 124–131 (Part 2); Air International, Vol. 12, No. 4, April 1977, pp. 171–180.
  • Haddon-Cave, Charles. "The Nimrod Review: an Independent Review into the Broader Issues Surrounding the Loss of the RAF Nimrod MR2 Aircraft XV230 in Afghanistan in 2006." The Stationery Office, 2009.
  • Jackson, A.J. British Civil Aircraft 1919-1972: Volume II. London: Putnam (Conway Maritime Press), 1988. ISBN 0-85177-813-5.
  • Jackson, A.J. De Havilland Aircraft since 1909. London: Putnam, Third edition, 1987. ISBN 0-85177-802-X.
  • Job, Macarthur. Air Disaster: Volume 1. Fyshwick, Australian Capital Territory: Aerospace Publications, 1996. ISBN 1-875671-11-0.
  • Lo Bao, Phil, ed. The de Havilland Comet (Airlines & Airliners). Middlesex, UK: The Aviation Data Centre Ltd., 1996.
  • McNeil, Ian, ed. An Encyclopedia of the History of Technology. London: Routledge, 2002 (E-edition), First edition 1990. ISBN 0-20319-211-7.
  • Roach, J.R and A.B. Eastwood. Jet Airliner Production List. West Drayton, UK: The Aviation Hobby Shop, 1992, ISBN 0-907178-43-X.
  • Taylor, John W. R. Jane's All The World's Aircraft 1965–66. London:Sampson Low, Marston & Company, 1965.
  • Trischler, Helmuth and Stefan Zeilinger. Tackling transport. London: NMSI Trading Ltd, 2003. ISBN 1-90074-753-7.
  • Walker, Timothy. The First Jet Airliner: The Story of the de Havilland Comet. Newcastle-Upon-Tyne, UK: Scoval Publishing Ltd., 2000. ISBN 1-902236-05-X.
  • Winchester, Jim, ed. "De Havilland DH.106 Comet." Civil Aircraft (The Aviation Factfile). London: Grange Books plc, 2004. ISBN 1-85013-642-1.
  • Withun, Bill. "Triumph, Tragedy and Triumph Again… The Comet Story." Air Classics Airliner Special No. 2, Summer 1976.
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