De Havilland Comet
Unanswered Questions
Encyclopedia
The de Havilland DH 106 Comet was the world's first commercial jet airliner
to reach production. Developed and manufactured by de Havilland
at the Hatfield
, Hertfordshire
, United Kingdom headquarters, it first flew in 1949 and was a landmark in aeronautical design. It featured an extremely aerodynamically clean design with its four de Havilland Ghost
turbojet engines buried into the wings, a low-noise pressurised cabin, and large windows; for the era, it was an exceptionally comfortable design for passengers and showed signs of being a major success in the first year upon launching.
However, a few years after introduction into commercial service, Comet airframes began suffering from catastrophic metal fatigue
, which in combination with cabin pressurisation cycles, caused two well-publicised accidents where the aircraft tore apart in mid-flight. The Comet had to be withdrawn and extensively tested to discover the cause; the first incident had been incorrectly identified as having been caused by an onboard fire. Several contributory factors, such as window installation methodology, were also identified as exacerbating the problem. The Comet was extensively redesigned to eliminate this design flaw. Rival manufacturers meanwhile developed their own aircraft and heeded the lessons learned from the Comet.
Although sales never fully recovered, the redesigned Comet 4 series subsequently enjoyed a long and productive career of over 30 years. The Comet was adapted for a variety of military roles, such as surveillance, VIP, medical and passenger transport; 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.
, the Brabazon Committee
was formed on 11 March 1943 to determine Britain's postwar airliner needs. One of the recommendations set a design "target" of a pressurised, transatlantic mailplane that could carry a ton of payload at a cruising speed of 400 mph (640 km/h). Challenging the widely held scepticism of jet engines as too fuel-hungry and unreliable, committee member Sir Geoffrey de Havilland
, head of the de Havilland company, used his influence and the company's expertise with jets to specify a turbojet-powered design. The committee accepted the proposal, calling it the "Type IV" (of five designs), and awarded the production contract to de Havilland's Type 106. The first-phase designs focused on short and intermediate range mailplanes with a small passenger compartment and as few as six seats, later redefined as a long-range airliner with 24-seat capacity. Out of all the Brabazon designs, the DH 106 was seen as the riskiest in terms of both introducing untried design elements and for the financial commitment involved. Nevertheless, British Overseas Airways Corporation
(BOAC) found the Type IV's specifications attractive, initially proposing a purchase of 25 aircraft and, in December 1945, when a "firm contract" was laid out, revising the number to 10.
A design team was formed in 1946 under the leadership of Chief Designer Ronald Bishop
, who had been responsible for the Mosquito
fighter-bomber. A number of unorthodox configurations were considered, all of which were subsequently rejected. The Ministry of Supply was interested in the most radical of the proposed designs and issued Operational Requirement OR207 to Specification E.18/45 for two experimental DH 108s ordered as "proof-of-concept" aircraft to test swept-wing configurations in both low-speed and high-speed flight.
Even before the DH 108s were completed, further requests from BOAC necessitated a redesign of the DH 106 from the original four-engined (Halford H.1 Goblin-powered) 24-seat airliner to a larger 36-seat version to specification 22/46 in September 1946. With no time to develop the technology required for the tailless configuration, Bishop opted for a more conventional 20˚ swept-wing design with unswept tail surfaces, married to an enlarged fuselage accommodating 36 passengers, arranged four abreast with a central aisle. Four new, more powerful Rolls-Royce Avon
s were to be incorporated in pairs buried in the wing roots, but Halford H.2 Ghost
engines were eventually specified as an interim solution while the Avons cleared certification. The redesigned DH 106 was named the DH 106 Comet in December 1947. First revised orders for both BOAC and British South American Airways for a combined total of 14 aircraft had a projected delivery schedule set for 1952.
for small components and large assemblies. Sections of the pressurised fuselage were subjected to the conditions of a flight at altitude in the company's decompression chamber. The DH 108s were also modified to test the DH 106's power controls.
The first flight of the first prototype DH 106 Comet (carrying Class B markings
G-5-1) took place on 27 July 1949 from Hatfield
, and lasted 31 minutes. 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
." Also on board were co-pilot Harold "Tubby" Waters, engineers John Wilson (electrics) and Frank Reynolds (hydraulics), along with flight test observer Tony Fairbrother
. Fairbrother commented, "The world changed as our wheels left the ground."
G-5-1 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. Both prototypes were distinguished by large main wheel units that were replaced by four-wheeled bogie
s on each main leg for the subsequent production series.
50 Mk1 turbojet engines were buried into the wings.
The Comet, approximately the length of a Boeing 737
, carried fewer people in a significantly more spacious environment. 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 on 45 inches (1,143 mm) centres. The cabin was quieter than those of propeller-driven airliners. Amenities included a galley
that could serve hot and cold food and drinks, a bar, and separate men's and women's washrooms. For emergencies, life raft
s were stored in the wings near the engines and life vest
s were stowed under each seat bottom.
In 1953, Sud-Est
's design bureau, while working on the Sud Aviation Caravelle
, licensed several design features from de Havilland, a company Sud had previously collaborated with on earlier licenced designs, including the DH 100 Vampire
. The entire nose and cockpit layout from the Comet 1 was grafted onto the Caravelle.
50 Mk1 turbojet engines buried in the wings close to the fuselage. Chief Designer Bishop chose this configuration because it avoided the drag of podded engine
s and allowed for a smaller fin and rudder
, since the hazards of asymmetric thrust were reduced. The engines' higher mounting in the wings also reduced the risk of ingestion damage (foreign object damage
[FOD]), 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. 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 altitude conditions from airports such as Khartoum
and Nairobi
. These were tested on 30 flights, but the Ghosts were considered powerful enough without them, although Sprite fittings were kept on production aircraft. The later Comet 4 was highly rated for its takeoff performance from high altitude locations such as Mexico City. Newer and more powerful AJ.65 Avon
engines replaced the Ghosts on the Comet 2. 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 had the advantage of requiring low maintenance, the de Havilland Ghost engines being a key contributing factor. Mounting the engines in a low-wing position combined with the placement of service panels allowed for easy and efficient maintenance. The fuel system incorporated underwing pressure refuelling, developed by Flight Refuelling Ltd
, which allowed much faster refilling of fuel tanks than was possible previously.
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 riveted and chemically bonded, which saved weight and reduced the risk of fatigue cracks spreading from the rivets. The chemical bonding process was accomplished using a new adhesive
, Redux
, which was heavily used in the construction of the wings and the fuselage of the Comet, it also had the advantage of simplifying the manufacture. The range of geographical destinations and the level of cabin pressurisation alike on the Comet demanded the use of a great deal of alloys, plastics, and other materials new to civil aviation across the aircraft in order to meet requirements.
When it went into service with BOAC on 2 May 1952, the Comet was the most exhaustively tested airliner in history. After the Comet entered production, for safety reasons, and to limit the damage to the specimens, a water tank was used instead of the decompression chamber. The entire forward fuselage section was tested for metal fatigue by repeatedly pressurising to 2.75 pound per square inches (19 kPa) overpressure and depressurising through more than 16,000 cycles, equivalent to about 40,000 hours of airline service. The windows were tested under a pressure of 12 psi (82.7 kPa), 4.75 psi (32.8 kPa) above the normal service ceiling of 36000 ft (10,972.8 m). One window frame survived a massive 100 psi (689.5 kPa), about 1,250% over the maximum pressure it would encounter in service.
. The last Comet from the initial order (G-ALYZ) began flying in September 1952, carrying cargo along South America
n routes while simulating passenger schedules.
The Comet was a hit with passengers including Queen Elizabeth, the Queen Mother
and Princess Margaret
, who were guests on a special flight on 30 June 1953 hosted by Sir Geoffrey and Lady de Havilland, and thus became the first members of the British Royal Family to fly by jet. A total of 30,000 passengers was carried during the first year of service. For the travelling public, the Comet offered flights about 50% faster than advanced piston-engined types such as 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. In August 1953 BOAC scheduled the Comet London to Tokyo in 35 hours, compared to 85 hr 35 min for their Argonaut
; Pan Am's DC-6B
flight 2 was scheduled 46 hr 45 min. Smooth, quiet jet flight was a new experience for passengers used to piston-engined airliners (although passengers of today would consider it noisy, particularly when seated aft of the wing). BOAC's Comets featured the BOAC-designed "slumberseat"; a comfortable, reclining design, allowing for greater leg room in front and behind. The large "picture window" view and accommodations for a table setting for a row of passengers afforded a "feel of comfort and luxury" atypical of airliners of the period. One of the most striking aspects of flight on the Comet was the quiet, "vibration-free flying" touted by BOAC.
Commercial success was widely expected, with a profitable passenger load factor as low as 43%. The Ghost engine was smooth, relatively simple, fuel-efficient above 30,000 ft (9,144 m), had low maintenance costs, and enabled operations above weather the competition had to fly through. At the height of Comet's early flying career, the BOAC Comet 1 fleet flew routes such as London-Singapore, London-Tokyo, and London-Johannesburg several times a week.
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. On 3 March 1953, a new Canadian Pacific Airlines
Comet 1A (CF-CUN), 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 fatal crash of a passenger jet airliner.
Both of these accidents were originally attributed to pilot error as over-rotation had led to a loss of lift from the leading edge of the aircraft's wing. It was later determined 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 with a pronounced "droop", and a wing fence
was added to control spanwise flow. A fictionalised investigation into these takeoff accidents was the subject of the 1959 novel, Cone of Silence by Arthur 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.
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
, killing all 43 on board. The crash was attributed to structural failure of the airframe with witnesses observing the wingless Comet on fire plunging into the Indian Ocean.
s encountered in the thundersquall
. A large proportion of the aircraft was recovered and reassembled at Farnborough. The break-up was found to have begun with a left-hand elevator spar failure in the stabiliser
. The immediate focus was on the severe turbulence encountered that induced down-loading, which subsequently precipitated the loss of the wings. Examination of the cockpit controls led to a belief that the pilot may have inadvertently overstressed the aircraft when pulling out of a steep dive by over-manipulation of the fully powered flight controls
.
Recommendations from the court revolved around the enforcement of stricter "rough air" speed limits. The tragedy led to two significant developments: all Comets were equipped with "weather radar" and the introduction of "Q feel", a system that ensured that control column forces (invariably called "stick forces") would be proportional to control loads. The artificial feel was the first of its kind to be introduced in any aircraft. The Comet 1 and 1A had been criticised for a lack of "feel
" in their controls, although test pilot John Cunningham contended, "it flew extremely smoothly and responded to the controls in the best way de Havilland aircraft usually did".
, broke up in flight and crashed into the Mediterranean off the Italian island of Elba
, with the loss of all 35 on board. With no witnesses to the disaster and only "sketchy" and incomplete radio transmissions left behind, there appeared to be no obvious reason for the crash. Engineers at de Havilland immediately recommended 60 modifications aimed at any possible design flaw while the Abell Committee met to determine potential causes of the crash.
; other speculation ranged from "clear-sky" turbulence to an explosion of vapour in an empty fuel tank. The committee soon focused on six potential aerodynamic and mechanical causes: control flutter (which had led to the loss of the de Havilland DH 108 Swallow prototypes), 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.
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 aircraft systems/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.
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
. The fleet was immediately grounded once again and a large investigation board was formed under the direction of the Royal Aircraft Establishment
(RAE). Prime Minister Winston Churchill
tasked the Royal Navy with helping locate and retrieve the wreckage so that the cause of the accident could be found. The type's Certificate of Airworthiness was revoked and line production suspended at Hatfield while the BOAC fleet was grounded.
On 19 October 1954, a court of inquiry was set up under the chairmanship of Lord Cohen
to examine the causes of the Comet crashes. Investigators under the leadership of Sir Arnold Hall
, Director of the RAE at Farnborough, began considering fatigue as the most likely cause of both accidents and initiated further research into measurable strain on the skin. With the recovery of large sections of G-ALYP from the Elba crash and G-ALYU, an extensive "water torture" test eventually provided conclusive results. 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. 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.
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. Dr. P.B. Walker, Head of the Structures Department (RAE) 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 1,000 to 9,000 cycles. Engineers subjected an identical airframe, G-ALYU, to repeated re-pressurisation and over-pressurisation, and on 24 June 1954, after 3,057 flight cycles (1,221 actual and 1,836 simulated), G-ALYU burst open. Hall, Geoffrey de Havilland and Bishop were immediately called to the scene, where the water tank was drained to reveal the fuselage had ripped open at a corner of the forward port-side escape hatch cutout. A further test reproduced the same results. 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 fibreglass forward "window" around the Automatic Direction Finder, had caused a catastrophic breakup of the aircraft in high altitude flight.
The rivet problem was exacerbated by the punch rivet construction technique employed. 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. Hall, 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."
The "Cohen Court" closed on 24 November 1954. Although the court "found that the basic design of the Comet was sound", nonetheless, de Havilland began a refit programme that involved strengthening the fuselage and wing structure, employing thicker gauge skin and replacing all square windows and panels with rounded ones.
As is often the case in aeronautical engineering, other aircraft manufacturers learned from, and profited by, de Havilland's hard-learned lessons. Although the Comet had been subjected to the most rigorous testing of any contemporary airliner, the "dynamic stresses" of pressurisation were not well known, and the "Comet had pushed 'the state-of-the-art' beyond its limits." According to John Cunningham
, representatives from American manufacturers such as Boeing
and Douglas
(privately) "admitted that if it hadn't been for our [de Havilland's] problems, it would have happened to one of them".
as the Comet C2. Development flying and route proving with the Comet 3 allowed BOAC to accelerate the certification of what was destined to be the most successful variant of the type. On 24 September 1958, the Comet 4 received a Certificate of Air Worthiness and, the next day, BOAC took delivery of its first two Comet 4s.
The Comet 4 enabled BOAC to inaugurate the first regular jet-powered transatlantic services to begin that same year, albeit the westward North Atlantic crossing still required a fuel stop at Gander International Airport
, Newfoundland
. BOAC got publicity by being the first across the Atlantic with the London to New York crossing on 4 October 1958, but by the end of the month Pan Am
was flying the Boeing 707 along the same route and in 1959-60 the Douglas DC-8 would be ready. The American jets were larger, faster, longer-ranged, and more cost-effective to operate than the Comet. In analysing the route structure the Comet could fly effectively, BOAC reluctantly cast about for a successor and, by 1958, had entered into an agreement with Boeing to purchase the 707.
In 1959 BOAC began shifting its Comet operations from the Atlantic run to other routes and releasing the Comet to the associate companies, the moves resulting in the Comet 4's ascendancy as a premier airliner being relatively brief. Besides the 707/DC-8 duo, the imminent introduction of the Vickers VC10
meant the Comet's competitors assumed more of the role initially pioneered by the Comet, that of high-speed, long-range passenger service. Orders from other air carriers were gradually falling off in the 1960s with a total of 76 of the Comet 4 family 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 48 remaining airworthy civil Comets. On 14 March 1997, a Comet 4C (XS235) which had been acquired by the British Ministry of Technology
and used for radio, radar and avionics trials, made the last documented Comet flight.
radar; the crew of four would be housed in a pressurised cockpit under a large bubble canopy. Additional fuel tanks carrying 2400 gallons (10,910.6 l) were built into the fuselage to attain a range of 3350 miles. The DH 111 proposal was evaluated by the Royal Aircraft Establishment
but serious concerns regarding weapons storage led to a negative RAE review. The capability of the proposed V bomber
trio also made the DH 111 redundant and further development work at de Havilland was abandoned on 22 October 1948.
engines, which all improved the aircraft's range and performance; some of these changes had been made to make the aircraft more suitable for transatlantic operations. Following the Comet 1 disasters, these models were rebuilt with heavier gauge skin and rounded windows, and the Avon engines featuring larger air intakes and "outward-curving" jet tailpipes. A total of 12 of the 44-seat Comet 2s were ordered by BOAC for the South Atlantic route. The first production aircraft (G-AMXA) flew on 27 August 1953. Although these aircraft performed well on test flights on the South Atlantic, their range was still not suitable for the North Atlantic. All but four Comet 2s were allocated to the RAF with deliveries beginning in 1955. Modifications to the interiors allowed the Comet 2s to be used in a number of different roles. For VIP transport, the seating and accommodations were altered while provisions for carrying medical equipment including iron lungs was incorporated. Specialised ELINT and electronic survelillance capability was later added to some airframes.
The Comet 3, which flew for the first time on 19 July 1954, was a lengthened Comet 2 powered by Avon M502 engines developing 10000 lbf (44.5 kN) with greater capacity and range, including the addition of wing pinion tanks. The Comet 3 was destined to remain a development series since it did not incorporate the fuselage-strengthening modifications of the later series aircraft, and was not able to be fully pressurised. Only two Comet 3s were constructed with G-ANLO, the only "flying" Comet 3, demonstrated at the Farnborough SBAC Show in September 1954. 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. Nine additional Comet 3 airframes were not completed and their construction was abandoned at Hatfield. In BOAC colours, G-ANLO was flown by John Cunningham in a marathon round-the-world promotional tour in December 1955. As a flying testbed, it was later modified with Avon RA29 engines fitted, as well as replacing the original long-span wings with reduced span wings as the Comet 3B and demonstrated in British European Airways
(BEA) livery at the Farnborough Airshow in September 1958. Assigned in 1961 to the Blind Landing Experimental Unit (BLEU) at RAE Bedford, the final testbed role played by G–ANLO was in "autoland
" experiments. 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.
BOAC ordered 19 Comet 4s in March 1955, with G-APDA first flying on 27 April 1958. Deliveries to the airline began on 30 September 1958 with two 48-seat aircraft. BOAC's G-APDC initiated 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
, Newfoundland
on 4 October 1958. Rival Pan Am
's inaugural Boeing 707 service began later that month.
BEA's Comets received a welcome response from crews and passengers but they were not so well liked by the baggage handler
s. The baggage/cargo holds had doors directly underneath the aircraft, so 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, then slid along the hold floor to be stacked inside. Likewise, the individual pieces of luggage and cargo had to be retrieved slowly with great effort on arrival.
American operator Capital Airlines
ordered 14 Comet 4s 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 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.
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 4C (SA-R-7) was ordered by Saudi Arabian Airlines with eventual disposition to the Saudi Royal Flight
for the exclusive use of King Saud bin Abdul Aziz
. Extensively modified at the factory, the aircraft included a VIP front cabin, a bed, special toilets with gold fittings and was distinguished by a resplendent green, gold and white colour scheme with polished wings and lower fuselage that was commissioned from aviation artist John Stroud. Following its first flight, the special order Comet 4C was described as "the world's first executive jet."
engines. Without support from the Ministry of Transport
, the proposal languished as a "paper project" only.
, designated Type HS 801. This variant became the Hawker Siddeley Nimrod and was built at the Hawker Siddeley factory at Woodford Aerodrome. Entering service in 1969, five Nimrod variants were produced. The final Nimrod aircraft were retired in June 2011.
Comet 2:
Comet 4
:
:
:
(Ceylon):
East African Community
(Kenya, Tanzania, Uganda):
:
:
:
:
:
:
:
/ :
:
:
:
South Africa
:
:
Canada:
:
:
:
:
:
Jet airliner
A jet airliner is an airliner that is powered by jet engines. This term is sometimes contracted to jetliner or jet.In contrast to today's relatively fuel-efficient, turbofan-powered air travel, first generation jet airliner travel was noisy and fuel inefficient...
to reach production. Developed and manufactured by de Havilland
De Havilland
The de Havilland Aircraft Company was a British aviation manufacturer founded in 1920 when Airco, of which Geoffrey de Havilland had been chief designer, was sold to BSA by the owner George Holt Thomas. De Havilland then set up a company under his name in September of that year at Stag Lane...
at the Hatfield
Hatfield Aerodrome
Hatfield Aerodrome, formerly , was an airfield and aircraft factory located in the town of Hatfield, Hertfordshire from 1930 until its closure and redevelopment in the 1990s.-Early history:...
, Hertfordshire
Hertfordshire
Hertfordshire is a ceremonial and non-metropolitan county in the East region of England. The county town is Hertford.The county is one of the Home Counties and lies inland, bordered by Greater London , Buckinghamshire , Bedfordshire , Cambridgeshire and...
, United Kingdom headquarters, it first flew in 1949 and was a landmark in aeronautical design. It featured an extremely aerodynamically clean design with its four de Havilland Ghost
De Havilland Ghost
|-See also:-Bibliography:*Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9...
turbojet engines buried into the wings, a low-noise pressurised cabin, and large windows; for the era, it was an exceptionally comfortable design for passengers and showed signs of being a major success in the first year upon launching.
However, a few years after introduction into commercial service, Comet airframes began suffering from catastrophic metal fatigue
Fatigue (material)
'In materials science, fatigue is the progressive and localized structural damage that occurs when a material is subjected to cyclic loading. The nominal maximum stress values are less than the ultimate tensile stress limit, and may be below the yield stress limit of the material.Fatigue occurs...
, which in combination with cabin pressurisation cycles, caused two well-publicised accidents where the aircraft tore apart in mid-flight. The Comet had to be withdrawn and extensively tested to discover the cause; the first incident had been incorrectly identified as having been caused by an onboard fire. Several contributory factors, such as window installation methodology, were also identified as exacerbating the problem. The Comet was extensively redesigned to eliminate this design flaw. Rival manufacturers meanwhile developed their own aircraft and heeded the lessons learned from the Comet.
Although sales never fully recovered, the redesigned Comet 4 series subsequently enjoyed a long and productive career of over 30 years. The Comet was adapted for a variety of military roles, such as surveillance, VIP, medical and passenger transport; 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
Royal Air Force
The Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...
(RAF) until they were retired in June 2011, over 60 years after the Comet's first flight.
Origins
During the Second World WarWorld War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, the Brabazon Committee
Brabazon Committee
The Brabazon Committee was a committee formed on 23 December 1942 to investigate the future needs of the British Empire's civilian airliner market...
was formed on 11 March 1943 to determine Britain's postwar airliner needs. One of the recommendations set a design "target" of a pressurised, transatlantic mailplane that could carry a ton of payload at a cruising speed of 400 mph (640 km/h). Challenging the widely held scepticism of jet engines as too fuel-hungry and unreliable, committee member Sir Geoffrey de Havilland
Geoffrey de Havilland
Captain Sir Geoffrey de Havilland, OM, CBE, AFC, RDI, FRAeS, was a British aviation pioneer and aircraft engineer...
, head of the de Havilland company, used his influence and the company's expertise with jets to specify a turbojet-powered design. The committee accepted the proposal, calling it the "Type IV" (of five designs), and awarded the production contract to de Havilland's Type 106. The first-phase designs focused on short and intermediate range mailplanes with a small passenger compartment and as few as six seats, later redefined as a long-range airliner with 24-seat capacity. Out of all the Brabazon designs, the DH 106 was seen as the riskiest in terms of both introducing untried design elements and for the financial commitment involved. Nevertheless, British Overseas Airways Corporation
British Overseas Airways Corporation
The British Overseas Airways Corporation was the British state airline from 1939 until 1946 and the long-haul British state airline from 1946 to 1974. The company started life with a merger between Imperial Airways Ltd. and British Airways Ltd...
(BOAC) found the Type IV's specifications attractive, initially proposing a purchase of 25 aircraft and, in December 1945, when a "firm contract" was laid out, revising the number to 10.
A design team was formed in 1946 under the leadership of Chief Designer Ronald Bishop
Ronald Eric Bishop
Ronald Eric Bishop CBE FRAeS was the chief designer of the de Havilland Mosquito, one of the most famous aircraft of the Second World War.Bishop also designed the de Havilland Comet.-Career:...
, who had been responsible for the Mosquito
De Havilland Mosquito
The de Havilland DH.98 Mosquito was a British multi-role combat aircraft that served during the Second World War and the postwar era. It was known affectionately as the "Mossie" to its crews and was also nicknamed "The Wooden Wonder"...
fighter-bomber. A number of unorthodox configurations were considered, all of which were subsequently rejected. The Ministry of Supply was interested in the most radical of the proposed designs and issued Operational Requirement OR207 to Specification E.18/45 for two experimental DH 108s ordered as "proof-of-concept" aircraft to test swept-wing configurations in both low-speed and high-speed flight.
Even before the DH 108s were completed, further requests from BOAC necessitated a redesign of the DH 106 from the original four-engined (Halford H.1 Goblin-powered) 24-seat airliner to a larger 36-seat version to specification 22/46 in September 1946. With no time to develop the technology required for the tailless configuration, Bishop opted for a more conventional 20˚ swept-wing design with unswept tail surfaces, married to an enlarged fuselage accommodating 36 passengers, arranged four abreast with a central aisle. Four new, more powerful Rolls-Royce Avon
Rolls-Royce Avon
|-See also:-Bibliography:* Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9-External links:**** a 1955 Flight article on the development of the Avon...
s were to be incorporated in pairs buried in the wing roots, but Halford H.2 Ghost
De Havilland Ghost
|-See also:-Bibliography:*Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9...
engines were eventually specified as an interim solution while the Avons cleared certification. The redesigned DH 106 was named the DH 106 Comet in December 1947. First revised orders for both BOAC and British South American Airways for a combined total of 14 aircraft had a projected delivery schedule set for 1952.
Testing and prototypes
During 1947–1948, de Havilland undertook an extensive research and development phase, utilising a number of stress test rigs at HatfieldHatfield, Hertfordshire
Hatfield is a town and civil parish in Hertfordshire, England in the borough of Welwyn Hatfield. It has a population of 29,616, and is of Saxon origin. Hatfield House, the home of the Marquess of Salisbury, is the nucleus of the old town...
for small components and large assemblies. Sections of the pressurised fuselage were subjected to the conditions of a flight at altitude in the company's decompression chamber. The DH 108s were also modified to test the DH 106's power controls.
The first flight of the first prototype DH 106 Comet (carrying Class B markings
United Kingdom aircraft test serials
United Kingdom aircraft test serials are used to externally identify aircraft flown within the United Kingdom without a full Certificate of Airworthiness...
G-5-1) took place on 27 July 1949 from Hatfield
Hatfield Aerodrome
Hatfield Aerodrome, formerly , was an airfield and aircraft factory located in the town of Hatfield, Hertfordshire from 1930 until its closure and redevelopment in the 1990s.-Early history:...
, and lasted 31 minutes. The pilot was de Havilland Chief Test Pilot John Cunningham
John Cunningham (RAF officer)
Group Captain John "Cat's Eyes" Cunningham CBE, DSO & Two Bars, DFC & Bar, , was a British Royal Air Force night fighter ace during World War II and a test pilot, both before and after the war...
, 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
Concorde
Aérospatiale-BAC Concorde was a turbojet-powered supersonic passenger airliner, a supersonic transport . It was a product of an Anglo-French government treaty, combining the manufacturing efforts of Aérospatiale and the British Aircraft Corporation...
." Also on board were co-pilot Harold "Tubby" Waters, engineers John Wilson (electrics) and Frank Reynolds (hydraulics), along with flight test observer Tony Fairbrother
Tony Fairbrother
Anthony James Fairbrother was an English engineer who was the flight-test engineer on the maiden flight of the de Havilland DH.106 Comet 1, the world's first jet airliner, in 1949....
. Fairbrother commented, "The world changed as our wheels left the ground."
G-5-1 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
Bournemouth Airport
Bournemouth Airport is an airport located north-northeast of Bournemouth, in southern England...
under the registration G-ALZK and carried out 500 flying hours of crew training and route proving. Both prototypes were distinguished by large main wheel units that were replaced by four-wheeled bogie
Bogie
A bogie is a wheeled wagon or trolley. In mechanics terms, a bogie is a chassis or framework carrying wheels, attached to a vehicle. It can be fixed in place, as on a cargo truck, mounted on a swivel, as on a railway carriage/car or locomotive, or sprung as in the suspension of a caterpillar...
s on each main leg for the subsequent production series.
Overview
The Comet is an all-metal low-wing cantilever monoplane powered by four jet engines, it had a four-place cockpit occupied by two pilots, a flight engineer, and a navigator. The clean, low-drag design of the aicraft featured many unique or innovative design elements, including a swept-wing leading edge, integral wing fuel tanks, and four-wheel bogie main undercarriage units designed by de Havilland. Two pairs of de Havilland GhostDe Havilland Ghost
|-See also:-Bibliography:*Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9...
50 Mk1 turbojet engines were buried into the wings.
The Comet, approximately the length of a Boeing 737
Boeing 737
The Boeing 737 is a short- to medium-range, twin-engine narrow-body jet airliner. Originally developed as a shorter, lower-cost twin-engine airliner derived from Boeing's 707 and 727, the 737 has developed into a family of nine passenger models with a capacity of 85 to 215 passengers...
, carried fewer people in a significantly more spacious environment. The earliest Comets had 11 rows of seats with four seats to a row in the 1A configuration used by Air France
Air France
Air France , stylised as AIRFRANCE, is the French flag carrier headquartered in Tremblay-en-France, , and is one of the world's largest airlines. It is a subsidiary of the Air France-KLM Group and a founding member of the SkyTeam global airline alliance...
; BOAC used an even roomier arrangement of 36 seats on 45 inches (1,143 mm) centres. The cabin was quieter than those of propeller-driven airliners. Amenities included a galley
Galley (kitchen)
The galley is the compartment of a ship, train or aircraft where food is cooked and prepared. It can also refer to a land based kitchen on a naval base or a particular formed household kitchen.-Ship's kitchen:...
that could serve hot and cold food and drinks, a bar, and separate men's and women's washrooms. For emergencies, life raft
Lifeboat (shipboard)
A lifeboat is a small, rigid or inflatable watercraft carried for emergency evacuation in the event of a disaster aboard ship. In the military, a lifeboat may be referred to as a whaleboat, dinghy, or gig. The ship's tenders of cruise ships often double as lifeboats. Recreational sailors sometimes...
s were stored in the wings near the engines and life vest
Personal flotation device
A personal flotation device is a device designed to assist a wearer, either conscious or unconscious, to keep afloat.Devices designed and approved by authorities for use by...
s were stowed under each seat bottom.
In 1953, Sud-Est
Sud Aviation
Sud-Aviation was a French state-owned aircraft manufacturer, originating from the merger of Sud-Est and Sud-Ouest on March 1, 1957...
's design bureau, while working on the Sud Aviation Caravelle
Sud Aviation Caravelle
The Sud Aviation SE 210 Caravelle was the first short/medium-range jet airliner produced by the French Sud Aviation firm starting in 1955 . The Caravelle was one of the more successful European first generation jetliners, selling throughout Europe and even penetrating the United States market, with...
, licensed several design features from de Havilland, a company Sud had previously collaborated with on earlier licenced designs, including the DH 100 Vampire
De Havilland Vampire
The de Havilland DH.100 Vampire was a British jet-engine fighter commissioned by the Royal Air Force during the Second World War. Following the Gloster Meteor, it was the second jet fighter to enter service with the RAF. Although it arrived too late to see combat during the war, the Vampire served...
. The entire nose and cockpit layout from the Comet 1 was grafted onto the Caravelle.
Engines
The Comet was powered by two pairs of de Havilland GhostDe Havilland Ghost
|-See also:-Bibliography:*Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9...
50 Mk1 turbojet engines buried in the wings close to the fuselage. Chief Designer Bishop chose this configuration because it avoided the drag of podded engine
Podded engine
A podded engine is a jet engine in a pod, typically attached below the wing or to the tail of the aircraft. The pod itself is called a nacelle....
s and allowed for a smaller fin and rudder
Vertical stabilizer
The vertical stabilizers, vertical stabilisers, or fins, of aircraft, missiles or bombs are typically found on the aft end of the fuselage or body, and are intended to reduce aerodynamic side slip. It is analogical to a skeg on boats and ships.On aircraft, vertical stabilizers generally point upwards...
, since the hazards of asymmetric thrust were reduced. The engines' higher mounting in the wings also reduced the risk of ingestion damage (foreign object damage
Foreign object damage
Foreign Object Debris is a substance, debris or article alien to a vehicle or system which would potentially cause damage.Foreign Object Damage is any damage attributed to a foreign object that can be expressed in physical or economic terms that may or may not degrade the product's required...
[FOD]), 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. 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
Hydrogen peroxide
Hydrogen peroxide is the simplest peroxide and an oxidizer. Hydrogen peroxide is a clear liquid, slightly more viscous than water. In dilute solution, it appears colorless. With its oxidizing properties, hydrogen peroxide is often used as a bleach or cleaning agent...
-powered de Havilland Sprite
De Havilland Sprite
The Sprite was a British rocket engine built by de Havilland for use in RATO applications. For RATO use only a short burn time is required, with simplicity and light weight as major virtues...
booster rockets for takeoff
Takeoff
Takeoff is the phase of flight in which an aerospace vehicle goes from the ground to flying in the air.For horizontal takeoff aircraft this usually involves starting with a transition from moving along the ground on a runway. For balloons, helicopters and some specialized fixed-wing aircraft , no...
under hot and high altitude conditions from airports such as Khartoum
Khartoum
Khartoum is the capital and largest city of Sudan and of Khartoum State. It is located at the confluence of the White Nile flowing north from Lake Victoria, and the Blue Nile flowing west from Ethiopia. The location where the two Niles meet is known as "al-Mogran"...
and Nairobi
Nairobi
Nairobi is the capital and largest city of Kenya. The city and its surrounding area also forms the Nairobi County. The name "Nairobi" comes from the Maasai phrase Enkare Nyirobi, which translates to "the place of cool waters". However, it is popularly known as the "Green City in the Sun" and is...
. These were tested on 30 flights, but the Ghosts were considered powerful enough without them, although Sprite fittings were kept on production aircraft. The later Comet 4 was highly rated for its takeoff performance from high altitude locations such as Mexico City. Newer and more powerful AJ.65 Avon
Rolls-Royce Avon
|-See also:-Bibliography:* Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9-External links:**** a 1955 Flight article on the development of the Avon...
engines replaced the Ghosts on the Comet 2. High engine performance combined with a low weight (compared to the Boeing 707
Boeing 707
The Boeing 707 is a four-engine narrow-body commercial passenger jet airliner developed by Boeing in the early 1950s. Its name is most commonly pronounced as "Seven Oh Seven". The first airline to operate the 707 was Pan American World Airways, inaugurating the type's first commercial flight on...
and Douglas DC-8
Douglas DC-8
The Douglas DC-8 is a four-engined narrow-body passenger commercial jet airliner, manufactured from 1958 to 1972 by the Douglas Aircraft Company...
), and exceptionally clean design all contributed to its high performance. Early-model Comets had the advantage of requiring low maintenance, the de Havilland Ghost engines being a key contributing factor. Mounting the engines in a low-wing position combined with the placement of service panels allowed for easy and efficient maintenance. The fuel system incorporated underwing pressure refuelling, developed by Flight Refuelling Ltd
Cobham plc
Cobham plc is a British manufacturing company based in Wimborne Minster, Dorset, England. It is listed on the London Stock Exchange and is a constituent of the FTSE 250 Index...
, which allowed much faster refilling of fuel tanks than was possible previously.
Fuselage and testing process
Adhesive
An adhesive, or glue, is a mixture in a liquid or semi-liquid state that adheres or bonds items together. Adhesives may come from either natural or synthetic sources. The types of materials that can be bonded are vast but they are especially useful for bonding thin materials...
, Redux
Redux (adhesive)
Redux is the generic name of a family of phenyl–formaldehyde/polyvinyl–formal adhesives developed by Aero Research Limited at Duxford, UK, in the 1940s, subsequently produced by Ciba . The brand name is now used for a range of epoxy adhesives manufactured by Hexcel. The name is a...
, which was heavily used in the construction of the wings and the fuselage of the Comet, it also had the advantage of simplifying the manufacture. The range of geographical destinations and the level of cabin pressurisation alike on the Comet demanded the use of a great deal of alloys, plastics, and other materials new to civil aviation across the aircraft in order to meet requirements.
When it went into service with BOAC on 2 May 1952, the Comet was the most exhaustively tested airliner in history. After the Comet entered production, for safety reasons, and to limit the damage to the specimens, a water tank was used instead of the decompression chamber. The entire forward fuselage section was tested for metal fatigue by repeatedly pressurising to 2.75 pound per square inches (19 kPa) overpressure and depressurising through more than 16,000 cycles, equivalent to about 40,000 hours of airline service. The windows were tested under a pressure of 12 psi (82.7 kPa), 4.75 psi (32.8 kPa) above the normal service ceiling of 36000 ft (10,972.8 m). One window frame survived a massive 100 psi (689.5 kPa), about 1,250% over the maximum pressure it would encounter in service.
Introduction
The first production aircraft (G-ALYP) flew on 9 January 1951 and subsequently was on loan to BOAC for development flying by the Comet Unit. On 22 January 1952, G-ALYS was the first Comet to receive a Certificate of Airworthiness, six months ahead of schedule. As part of the BOAC route proving trials, on 2 May, G-ALYP took off on the world's first "jetliner" flight with fare-paying passengers, beginning scheduled service to JohannesburgJohannesburg
Johannesburg also known as Jozi, Jo'burg or Egoli, is the largest city in South Africa, by population. Johannesburg is the provincial capital of Gauteng, the wealthiest province in South Africa, having the largest economy of any metropolitan region in Sub-Saharan Africa...
. The last Comet from the initial order (G-ALYZ) began flying in September 1952, carrying cargo along South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
n routes while simulating passenger schedules.
The Comet was a hit with passengers including Queen Elizabeth, the Queen Mother
Elizabeth Bowes-Lyon
Elizabeth Angela Marguerite Bowes-Lyon was the queen consort of King George VI from 1936 until her husband's death in 1952, after which she was known as Queen Elizabeth The Queen Mother, to avoid confusion with her daughter, Queen Elizabeth II...
and Princess Margaret
Princess Margaret, Countess of Snowdon
Princess Margaret, Countess of Snowdon was the younger sister of Queen Elizabeth II and the younger daughter of King George VI....
, who were guests on a special flight on 30 June 1953 hosted by Sir Geoffrey and Lady de Havilland, and thus became the first members of the British Royal Family to fly by jet. A total of 30,000 passengers was carried during the first year of service. For the travelling public, the Comet offered flights about 50% faster than advanced piston-engined types such as the Douglas DC-6
Douglas DC-6
The Douglas DC-6 is a piston-powered airliner and transport aircraft built by the Douglas Aircraft Company from 1946 to 1958. Originally intended as a military transport near the end of World War II, it was reworked after the war to compete with the Lockheed Constellation in the long-range...
(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. In August 1953 BOAC scheduled the Comet London to Tokyo in 35 hours, compared to 85 hr 35 min for their Argonaut
Canadair North Star
The Canadair North Star was a 1940s Canadian development of the Douglas C-54 / DC-4 aircraft. Instead of radial piston engines found on the Douglas design, Canadair employed Rolls-Royce Merlin engines in order to achieve a 35 mph faster cruising speed. The prototype flew on 15 July 1946 and...
; Pan Am's DC-6B
Douglas DC-6
The Douglas DC-6 is a piston-powered airliner and transport aircraft built by the Douglas Aircraft Company from 1946 to 1958. Originally intended as a military transport near the end of World War II, it was reworked after the war to compete with the Lockheed Constellation in the long-range...
flight 2 was scheduled 46 hr 45 min. Smooth, quiet jet flight was a new experience for passengers used to piston-engined airliners (although passengers of today would consider it noisy, particularly when seated aft of the wing). BOAC's Comets featured the BOAC-designed "slumberseat"; a comfortable, reclining design, allowing for greater leg room in front and behind. The large "picture window" view and accommodations for a table setting for a row of passengers afforded a "feel of comfort and luxury" atypical of airliners of the period. One of the most striking aspects of flight on the Comet was the quiet, "vibration-free flying" touted by BOAC.
Commercial success was widely expected, with a profitable passenger load factor as low as 43%. The Ghost engine was smooth, relatively simple, fuel-efficient above 30,000 ft (9,144 m), had low maintenance costs, and enabled operations above weather the competition had to fly through. At the height of Comet's early flying career, the BOAC Comet 1 fleet flew routes such as London-Singapore, London-Tokyo, and London-Johannesburg several times a week.
Early accidents and incidents
On 26 October 1952, a BOAC flight departing from CiampinoCiampino
Ciampino is a town and comune in the province of Rome, Lazio, Italy. It was a frazione of Marino until 1974, when it became a comune; it obtained the city status in 2004 by presidential decree.-Overview:It is best known for the local "Giovan Battista Pastine" International Airport, best known as...
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. On 3 March 1953, a new Canadian Pacific Airlines
Canadian Pacific Airlines
Canadian Pacific Air Lines was a Canadian airline that operated from 1942 to 1987. It operated under the name CP Air from 1968 to 1986...
Comet 1A (CF-CUN), known as "Empress of Hawaii," being delivered to Australia, also failed to become airborne on takeoff from Karachi
Karachi
Karachi is the largest city, main seaport and the main financial centre of Pakistan, as well as the capital of the province of Sindh. The city has an estimated population of 13 to 15 million, while the total metropolitan area has a population of over 18 million...
, Pakistan
Pakistan
Pakistan , officially the Islamic Republic of Pakistan is a sovereign state in South Asia. It has a coastline along the Arabian Sea and the Gulf of Oman in the south and is bordered by Afghanistan and Iran in the west, India in the east and China in the far northeast. In the north, Tajikistan...
. The aircraft plunged into a dry drainage canal and collided with an embankment, killing all five crew and six passengers on board, the first fatal crash of a passenger jet airliner.
Both of these accidents were originally attributed to pilot error as over-rotation had led to a loss of lift from the leading edge of the aircraft's wing. It was later determined the wing profile led to a loss of lift at high angle of attack
Angle of attack
Angle of attack is a term used in fluid dynamics to describe the angle between a reference line on a lifting body and the vector representing the relative motion between the lifting body and the fluid through which it is moving...
, and the engine inlets suffered from a lack of pressure recovery in these conditions as well. The wing leading edge was re-profiled with a pronounced "droop", and a wing fence
Wing fence
Wing fences, also known as boundary layer fences and potential fences are fixed aerodynamic devices attached to aircraft wings. Not to be confused with wingtip fences, wing fences are flat plates fixed to the upper surfaces parallel to the airflow. They are often seen on swept-wing aircraft...
was added to control spanwise flow. A fictionalised investigation into these takeoff accidents was the subject of the 1959 novel, Cone of Silence by Arthur David Beaty, a former BOAC captain. Cone of Silence
Cone of Silence (1960 film)
Cone of Silence is a film about the investigation into a series of crashes involving the fictional "Atlas Aviation Phoenix" jetliner. In the United States, the film was released under the title Trouble in the Sky...
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.
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
Netaji Subhash Chandra Bose International Airport
Netaji Subhash Chandra Bose International Airport is an airport located in Kolkata, West Bengal, India, serving the greater Kolkata metro area. The airport was originally known as Dum Dum Airport before being renamed in the honour of Subhas Chandra Bose...
), India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, killing all 43 on board. The crash was attributed to structural failure of the airframe with witnesses observing the wingless Comet on fire plunging into the Indian Ocean.
India Court of Inquiry
A court of inquiry was convened by the Central Government of India to examine the cause of the accident. The conclusions of the inquiry focused on the extreme negative G forceG-force
The g-force associated with an object is its acceleration relative to free-fall. This acceleration experienced by an object is due to the vector sum of non-gravitational forces acting on an object free to move. The accelerations that are not produced by gravity are termed proper accelerations, and...
s encountered in the thundersquall
Squall
A squall is a sudden, sharp increase in wind speed which is usually associated with active weather, such as rain showers, thunderstorms, or heavy snow. Squalls refer to an increase in the sustained winds over a short time interval, as there may be higher gusts during a squall event...
. A large proportion of the aircraft was recovered and reassembled at Farnborough. The break-up was found to have begun with a left-hand elevator spar failure in the stabiliser
Tailplane
A tailplane, also known as horizontal stabilizer , is a small lifting surface located on the tail behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed wing aircraft such as helicopters and gyroplanes...
. The immediate focus was on the severe turbulence encountered that induced down-loading, which subsequently precipitated the loss of the wings. Examination of the cockpit controls led to a belief that the pilot may have inadvertently overstressed the aircraft when pulling out of a steep dive by over-manipulation of the fully powered flight controls
Aircraft flight control systems
A conventional fixed-wing aircraft flight control system consists of flight control surfaces, the respective cockpit controls, connecting linkages, and the necessary operating mechanisms to control an aircraft's direction in flight...
.
Recommendations from the court revolved around the enforcement of stricter "rough air" speed limits. The tragedy led to two significant developments: all Comets were equipped with "weather radar" and the introduction of "Q feel", a system that ensured that control column forces (invariably called "stick forces") would be proportional to control loads. The artificial feel was the first of its kind to be introduced in any aircraft. The Comet 1 and 1A had been criticised for a lack of "feel
Feedback
Feedback describes the situation when output from an event or phenomenon in the past will influence an occurrence or occurrences of the same Feedback describes the situation when output from (or information about the result of) an event or phenomenon in the past will influence an occurrence or...
" in their controls, although test pilot John Cunningham contended, "it flew extremely smoothly and responded to the controls in the best way de Havilland aircraft usually did".
Comet disasters of 1954
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 781BOAC Flight 781
On 10 January 1954, British Overseas Airways Corporation Flight 781 a de Havilland DH.106 Comet 1 registered G-ALYP, took off from Ciampino Airport in Rome, Italy, en route to Heathrow Airport in London, England, on the final leg of its flight from Singapore...
, broke up in flight and crashed into the Mediterranean off the Italian island of Elba
Elba
Elba is a Mediterranean island in Tuscany, Italy, from the coastal town of Piombino. The largest island of the Tuscan Archipelago, Elba is also part of the National Park of the Tuscan Archipelago and the third largest island in Italy after Sicily and Sardinia...
, with the loss of all 35 on board. With no witnesses to the disaster and only "sketchy" and incomplete radio transmissions left behind, there appeared to be no obvious reason for the crash. Engineers at de Havilland immediately recommended 60 modifications aimed at any possible design flaw while the Abell Committee met to determine potential causes of the crash.
Abell Committee Court of Inquiry
Media attention centred upon sabotageSabotage
Sabotage is a deliberate action aimed at weakening another entity through subversion, obstruction, disruption, or destruction. In a workplace setting, sabotage is the conscious withdrawal of efficiency generally directed at causing some change in workplace conditions. One who engages in sabotage is...
; other speculation ranged from "clear-sky" turbulence to an explosion of vapour in an empty fuel tank. The committee soon focused on six potential aerodynamic and mechanical causes: control flutter (which had led to the loss of the de Havilland DH 108 Swallow prototypes), structural failure due to high loads or metal fatigue
Fatigue (material)
'In materials science, fatigue is the progressive and localized structural damage that occurs when a material is subjected to cyclic loading. The nominal maximum stress values are less than the ultimate tensile stress limit, and may be below the yield stress limit of the material.Fatigue occurs...
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.
During this investigation, the Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
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 aircraft systems/equipment had been recovered. The forensic reconstruction effort was only lately underway when the Abell Committee reported their findings. On 4 April, Lord Brabazon
John Moore-Brabazon, 1st Baron Brabazon of Tara
John Theodore Cuthbert Moore-Brabazon, 1st Baron Brabazon of Tara, GBE, MC, PC was an English aviation pioneer and Conservative politician...
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.
On 8 April 1954, Comet G-ALYY ("Yoke Yoke"), on charter to South African Airways
South African Airways
South African Airways is the national flag carrier and largest airline of South Africa, with headquarters in Airways Park on the grounds of OR Tambo International Airport in Kempton Park, Ekurhuleni, Gauteng. The airline flies to 36 destinations worldwide from its hub at OR Tambo International...
, was on a leg from Rome to Cairo (of a longer flight from London to Johannesburg), when it crashed in the waters near Naples
Naples
Naples is a city in Southern Italy, situated on the country's west coast by the Gulf of Naples. Lying between two notable volcanic regions, Mount Vesuvius and the Phlegraean Fields, it is the capital of the region of Campania and of the province of Naples...
. The fleet was immediately grounded once again and a large investigation board was formed under the direction of the Royal Aircraft Establishment
Royal Aircraft Establishment
The Royal Aircraft Establishment , was a British research establishment, known by several different names during its history, that eventually came under the aegis of the UK Ministry of Defence , before finally losing its identity in mergers with other institutions.The first site was at Farnborough...
(RAE). Prime Minister Winston Churchill
Winston Churchill
Sir Winston Leonard Spencer-Churchill, was a predominantly Conservative British politician and statesman known for his leadership of the United Kingdom during the Second World War. He is widely regarded as one of the greatest wartime leaders of the century and served as Prime Minister twice...
tasked the Royal Navy with helping locate and retrieve the wreckage so that the cause of the accident could be found. The type's Certificate of Airworthiness was revoked and line production suspended at Hatfield while the BOAC fleet was grounded.
Cohen Committee Court of Inquiry
Lionel Cohen, Baron Cohen
Lionel Leonard Cohen, Baron Cohen PC , was a British judge.Invested to the privy council in 1946, Cohen was Lord Justice of Appeal from 1946 to 1951. On 12 November 1951, he was appointed Lord of Appeal in Ordinary and made additionally a life peer with the title Baron Cohen, of Walmer in the...
to examine the causes of the Comet crashes. Investigators under the leadership of Sir Arnold Hall
Arnold Alexander Hall
Sir Arnold Alexander Hall FRS was a British aeronautical engineer, scientist, and industrialist.-Life:Hall was born in Liverpool, and attended Alsop High School in Walton, before going to Clare College, Cambridge, where he won several prizes As a postgraduate he worked with Frank Whittle, then...
, Director of the RAE at Farnborough, began considering fatigue as the most likely cause of both accidents and initiated further research into measurable strain on the skin. With the recovery of large sections of G-ALYP from the Elba crash and G-ALYU, an extensive "water torture" test eventually provided conclusive results. 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. This was due to stress concentration
Stress concentration
A stress concentration is a location in an object where stress is concentrated. An object is strongest when force is evenly distributed over its area, so a reduction in area, e.g. caused by a crack, results in a localized increase in stress...
, 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.
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. Dr. P.B. Walker, Head of the Structures Department (RAE) 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 1,000 to 9,000 cycles. Engineers subjected an identical airframe, G-ALYU, to repeated re-pressurisation and over-pressurisation, and on 24 June 1954, after 3,057 flight cycles (1,221 actual and 1,836 simulated), G-ALYU burst open. Hall, Geoffrey de Havilland and Bishop were immediately called to the scene, where the water tank was drained to reveal the fuselage had ripped open at a corner of the forward port-side escape hatch cutout. A further test reproduced the same results. By then, the RAE had reconstructed about ⅔ of G-ALYP at Farnborough
Farnborough Airfield
Farnborough Airport or TAG London Farnborough Airport is an airport situated in Farnborough, Rushmoor, Hampshire, England...
and found fatigue crack growth from a rivet hole at the low-drag fibreglass forward "window" around the Automatic Direction Finder, had caused a catastrophic breakup of the aircraft in high altitude flight.
The rivet problem was exacerbated by the punch rivet construction technique employed. 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. Hall, 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."
The "Cohen Court" closed on 24 November 1954. Although the court "found that the basic design of the Comet was sound", nonetheless, de Havilland began a refit programme that involved strengthening the fuselage and wing structure, employing thicker gauge skin and replacing all square windows and panels with rounded ones.
As is often the case in aeronautical engineering, other aircraft manufacturers learned from, and profited by, de Havilland's hard-learned lessons. Although the Comet had been subjected to the most rigorous testing of any contemporary airliner, the "dynamic stresses" of pressurisation were not well known, and the "Comet had pushed 'the state-of-the-art' beyond its limits." According to John Cunningham
John Cunningham (RAF officer)
Group Captain John "Cat's Eyes" Cunningham CBE, DSO & Two Bars, DFC & Bar, , was a British Royal Air Force night fighter ace during World War II and a test pilot, both before and after the war...
, representatives from American manufacturers such as Boeing
Boeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...
and Douglas
Douglas Aircraft Company
The Douglas Aircraft Company was an American aerospace manufacturer, based in Long Beach, California. It was founded in 1921 by Donald Wills Douglas, Sr. and later merged with McDonnell Aircraft in 1967 to form McDonnell Douglas...
(privately) "admitted that if it hadn't been for our [de Havilland's] problems, it would have happened to one of them".
Resumption of service
The Comet did not resume commercial airline service until 1958. Following the structural problems of the early series, 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. 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 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), but 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 RAFRoyal Air Force
The Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...
as the Comet C2. Development flying and route proving with the Comet 3 allowed BOAC to accelerate the certification of what was destined to be the most successful variant of the type. On 24 September 1958, the Comet 4 received a Certificate of Air Worthiness and, the next day, BOAC took delivery of its first two Comet 4s.
The Comet 4 enabled BOAC to inaugurate the first regular jet-powered transatlantic services to begin that same year, albeit the westward North Atlantic crossing still required a fuel stop at Gander International Airport
Gander International Airport
Gander International Airport is located in Gander, Newfoundland and Labrador, Canada, and is currently run by the Gander Airport Authority. Canadian Forces Base Gander shares the airfield but is a separate entity from the airport.-Early years and prominence:...
, Newfoundland
Gander, Newfoundland and Labrador
Gander is a Canadian town located in the northeastern part of the island of Newfoundland in the province of Newfoundland and Labrador, approximately south of Gander Bay, south of Twillingate and east of Grand Falls-Windsor...
. BOAC got publicity by being the first across the Atlantic with the London to New York crossing on 4 October 1958, but by the end of the month Pan Am
Pan American World Airways
Pan American World Airways, commonly known as Pan Am, was the principal and largest international air carrier in the United States from 1927 until its collapse on December 4, 1991...
was flying the Boeing 707 along the same route and in 1959-60 the Douglas DC-8 would be ready. The American jets were larger, faster, longer-ranged, and more cost-effective to operate than the Comet. In analysing the route structure the Comet could fly effectively, BOAC reluctantly cast about for a successor and, by 1958, had entered into an agreement with Boeing to purchase the 707.
In 1959 BOAC began shifting its Comet operations from the Atlantic run to other routes and releasing the Comet to the associate companies, the moves resulting in the Comet 4's ascendancy as a premier airliner being relatively brief. Besides the 707/DC-8 duo, the imminent introduction of the Vickers VC10
Vickers VC10
The Vickers VC10 is a long-range British airliner designed and built by Vickers-Armstrongs Ltd, and first flown in 1962. The airliner was designed to operate on long-distance routes with a high subsonic speed and also be capable of hot and high operations from African airports...
meant the Comet's competitors assumed more of the role initially pioneered by the Comet, that of high-speed, long-range passenger service. Orders from other air carriers were gradually falling off in the 1960s with a total of 76 of the Comet 4 family 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
Dan-Air
Dan-Air was a leading private, independentindependent from government-owned corporations airline based in the United Kingdom....
played a significant role in the fleet's later history and, at one time, owned all 48 remaining airworthy civil Comets. On 14 March 1997, a Comet 4C (XS235) which had been acquired by the British Ministry of Technology
Minister of Technology
The Minister of Technology was a position in the government of the United Kingdom, sometimes abbreviated as "MinTech". The Ministry of Technology was established by the incoming government of Harold Wilson in October 1964 as part of Wilson's ambition to modernise the state for what he perceived to...
and used for radio, radar and avionics trials, made the last documented Comet flight.
Comet 1
The square-windowed Comet 1 was the first model produced, a total of 12 aircraft in service and test. Following closely the design features of the two prototypes, the only noticeable change was the adoption of four-wheel bogie main undercarriage units, replacing the single main wheels. Four 5050 lbf (22.5 kN) Ghost 50 Mk 1 (later 5700 lbf (25.4 kN) Ghost DGT3 series) engines were fitted. The span was 115 ft (35.05 m), length 93 ft (28.35 m), Maximum Takeoff Weight 105,000 lb (47.628 kg) with 36–48 passenger configurations.- An updated Comet 1A was offered with higher allowed weight and water-methanol injection; 10 were produced. In the wake of the 1954 disasters, all Comet 1s and 1As were brought back to Hatfield, first placed in a protective "cocoon" and retained for testing. All were substantially damaged in stress testing or were scrapped entirely.
- Comet 1X: Two RCAF Comet 1As were rebuilt with heavier-gauge skins to a Comet 2 standard for the fuselage, and renamed Comet 1X.
- Comet 1XB: Four Comet 1As were upgraded to a 1XB standard with a reinforced fuselage structure and oval windows. Both 1X series were limited in number of pressurisation cycles.
DH 111 Comet Bomber
Originally proposed in 1948 as the "PR Comet", a "high-level photo reconnaissance" adaptation of the Comet 1, de Havilland further developed a bomber variant to Air Ministry specification B35/46 as the DH 111 Comet Bomber with a submission to the Air Ministry on 27 May 1948. The substantially altered airframe powered by four 5700 lbf (25.4 kN) Ghost DGT3 engines, was designed around the "special bomb", and featured a "narrowed fuselage" along with a bulbous nose to accommodate the H2S Mk IXH2S radar
H2S was the first airborne, ground scanning radar system. It was developed in Britain in World War II for the Royal Air Force and was used in various RAF bomber aircraft from 1943 to the 1990s. It was designed to identify targets on the ground for night and all-weather bombing...
radar; the crew of four would be housed in a pressurised cockpit under a large bubble canopy. Additional fuel tanks carrying 2400 gallons (10,910.6 l) were built into the fuselage to attain a range of 3350 miles. The DH 111 proposal was evaluated by the Royal Aircraft Establishment
Royal Aircraft Establishment
The Royal Aircraft Establishment , was a British research establishment, known by several different names during its history, that eventually came under the aegis of the UK Ministry of Defence , before finally losing its identity in mergers with other institutions.The first site was at Farnborough...
but serious concerns regarding weapons storage led to a negative RAE review. The capability of the proposed V bomber
V bomber
The term V bomber was used for the Royal Air Force aircraft during the 1950s and 1960s that comprised the United Kingdom's strategic nuclear strike force known officially as the V-force or Bomber Command Main Force...
trio also made the DH 111 redundant and further development work at de Havilland was abandoned on 22 October 1948.
Comet 2
The Comet 2 had a slightly larger wing, higher fuel capacity and more powerful Rolls-Royce AvonRolls-Royce Avon
|-See also:-Bibliography:* Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9-External links:**** a 1955 Flight article on the development of the Avon...
engines, which all improved the aircraft's range and performance; some of these changes had been made to make the aircraft more suitable for transatlantic operations. Following the Comet 1 disasters, these models were rebuilt with heavier gauge skin and rounded windows, and the Avon engines featuring larger air intakes and "outward-curving" jet tailpipes. A total of 12 of the 44-seat Comet 2s were ordered by BOAC for the South Atlantic route. The first production aircraft (G-AMXA) flew on 27 August 1953. Although these aircraft performed well on test flights on the South Atlantic, their range was still not suitable for the North Atlantic. All but four Comet 2s were allocated to the RAF with deliveries beginning in 1955. Modifications to the interiors allowed the Comet 2s to be used in a number of different roles. For VIP transport, the seating and accommodations were altered while provisions for carrying medical equipment including iron lungs was incorporated. Specialised ELINT and electronic survelillance capability was later added to some airframes.
- 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 T2: The first two of 10 Comet 2s for the RAF were fitted out as crew trainers, with the first aircraft (XK669) flying for the first time on 9 December 1955.
- Comet C2: Eight Comet 2s originally destined for the civil market were completed for the RAF and assigned to No. 216 SquadronNo. 216 Squadron RAFNo. 216 Squadron of the Royal Air Force operates the Lockheed Tristar K1, KC1 and C2 from RAF Brize Norton, Oxfordshire.- History :216 Squadron was formed at RAF Manston by re-numbering No. 16 Squadron RNAS when the RAF was established in 1918, hence it is always spoken of as 'two-sixteen Squadron'...
. - Comet 2R: Three Comet 2s were modified for use in radar and electronic systems development, initially assigned to No. 90 Group (later Signals CommandRAF Signals CommandSignals Command was the RAF's command responsible for control of signals units from 1958 to 1969. It was based at RAF Medmenham near Marlow, Buckinghamshire.-History:The Command was formed on 3 November 1958 by raising No. 90 Group to Command status...
) for the RAF. In service with No. 192No. 192 Squadron RAFNo. 192 Squadron was a Royal Air Force squadron, operational during the First World War as a night training squadron, and during the Second World War as a radar countermeasure unit. After the war the squadron served again in the Electronic Intelligence role, until disbanded.-Formation in World War...
and No. 51 SquadronNo. 51 Squadron RAFNo. 51 Squadron of the Royal Air Force most recently operated the Nimrod R1 from RAF Waddington, Lincolnshire until June 2011. Crews from No. 51 Squadron are currently training alongside the US Air Force on the Boeing RC-135, which is planned to enter service with the RAF over the next seven years...
s, the 2R series were equipped to monitor Warsaw PactWarsaw PactThe Warsaw Treaty Organization of Friendship, Cooperation, and Mutual Assistance , or more commonly referred to as the Warsaw Pact, was a mutual defense treaty subscribed to by eight communist states in Eastern Europe...
signal traffic and operated in this role from 1958.
Comet 3
British European Airways
British European Airways or British European Airways Corporation was a British airline which existed from 1946 until 1974. The airline operated European and North African routes from airports around the United Kingdom...
(BEA) livery at the Farnborough Airshow in September 1958. Assigned in 1961 to the Blind Landing Experimental Unit (BLEU) at RAE Bedford, the final testbed role played by G–ANLO was in "autoland
Autoland
In aviation, autoland describes a system that fully automates the landing phase of an aircraft's flight, with the human crew merely supervising the process.-Description:...
" experiments. When retired in 1973, the airframe was used for foam arrester trials before the fuselage was salvaged at BAE Woodford
Woodford, Greater Manchester
Woodford is a suburban village at the southern extent of the Metropolitan Borough of Stockport, in Greater Manchester, England. It lies south of Stockport, north-northwest of Macclesfield, and south-southeast of Manchester...
, to serve as the mock-up for the Nimrod.
Comet 4
The Comet 4 was a further improvement on the stretched Comet 3 with even greater fuel capacity. The design had progressed significantly from the original Comet 1, growing by 18 ft 6 in (5.64 m) and typically seating 74 to 81 passengers compared to the Comet 1's 36 to 44. The Comet 4 was considered the definitive series, having a longer range, higher cruising speed and higher maximum takeoff weight. These improvements were possible largely because of Avon engines with twice the thrust of the Comet 1's Ghosts.BOAC ordered 19 Comet 4s in March 1955, with G-APDA first flying on 27 April 1958. Deliveries to the airline began on 30 September 1958 with two 48-seat aircraft. BOAC's G-APDC initiated 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
Gander International Airport
Gander International Airport is located in Gander, Newfoundland and Labrador, Canada, and is currently run by the Gander Airport Authority. Canadian Forces Base Gander shares the airfield but is a separate entity from the airport.-Early years and prominence:...
, Newfoundland
Newfoundland and Labrador
Newfoundland and Labrador is the easternmost province of Canada. Situated in the country's Atlantic region, it incorporates the island of Newfoundland and mainland Labrador with a combined area of . As of April 2011, the province's estimated population is 508,400...
on 4 October 1958. Rival Pan Am
Pan American World Airways
Pan American World Airways, commonly known as Pan Am, was the principal and largest international air carrier in the United States from 1927 until its collapse on December 4, 1991...
's inaugural Boeing 707 service began later that month.
BEA's Comets received a welcome response from crews and passengers but they were not so well liked by the baggage handler
Baggage handler
In the airline industry, a baggage handler is a person who loads and unloads baggage , and other cargo for transport via aircraft...
s. The baggage/cargo holds had doors directly underneath the aircraft, so 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, then slid along the hold floor to be stacked inside. Likewise, the individual pieces of luggage and cargo had to be retrieved slowly with great effort on arrival.
American operator Capital Airlines
Capital Airlines
Capital Airlines was an airline serving the eastern United States that merged into United Airlines in 1961. Its primary hubs were National Airport near Washington, DC, and Allegheny County Airport near Pittsburgh. In the 1950s it was the largest US domestic carrier after the Big Four . Its...
ordered 14 Comet 4s 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 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.
Mexicana de Aviación
Founded in 1921, Compañía Mexicana de Aviación, S.A. de C.V. was Mexico's oldest airline, before ceasing operations on August 28, 2010. The group's closure was announced by the company's recently installed management team a short time after the group filed for Concurso Mercantil and US Chapter 15...
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 4C (SA-R-7) was ordered by Saudi Arabian Airlines with eventual disposition to the Saudi Royal Flight
Royal Saudi Air Force
The Royal Saudi Air Force , is the aviation branch of the Saudi Arabian armed forces. The RSAF has developed from a largely defensive military force into one with an advanced offensive capability...
for the exclusive use of King Saud bin Abdul Aziz
Saud of Saudi Arabia
Saud bin Abdul-Aziz Al Saud was King of Saudi Arabia from 1953 to 1964. He was removed from power by Faisal because of Saud's mismanagement and waste. He was the eldest surviving son of Ibn Saud and became Crown Prince in 1933. He died in exile in Greece.-Early life:Saud was born in 1902 in Kuwait...
. Extensively modified at the factory, the aircraft included a VIP front cabin, a bed, special toilets with gold fittings and was distinguished by a resplendent green, gold and white colour scheme with polished wings and lower fuselage that was commissioned from aviation artist John Stroud. Following its first flight, the special order Comet 4C was described as "the world's first executive jet."
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 ConwayRolls-Royce Conway
The Rolls-Royce RB.80 Conway was the first by-pass engine in the world to enter service. Development started at Rolls-Royce in the 1940s, but it was used only briefly in the late 1950s and early 1960s before other turbofan designs were introduced that replaced it. The Conway powered versions of...
engines. Without support from the Ministry of Transport
Department for Transport
In the United Kingdom, the Department for Transport is the government department responsible for the English transport network and a limited number of transport matters in Scotland, Wales and Northern Ireland which are not devolved...
, the proposal languished as a "paper project" only.
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 ForceRoyal Air Force
The Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...
, designated Type HS 801. This variant became the Hawker Siddeley Nimrod and was built at the Hawker Siddeley factory at Woodford Aerodrome. Entering service in 1969, five Nimrod variants were produced. The final Nimrod aircraft were retired in June 2011.
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, although it never flew for that airline, having been delivered to Air FranceAir FranceAir France , stylised as AIRFRANCE, is the French flag carrier headquartered in Tremblay-en-France, , and is one of the world's largest airlines. It is a subsidiary of the Air France-KLM Group and a founding member of the SkyTeam global airline alliance...
and then to the Ministry of SupplyMinistry of SupplyThe Ministry of Supply was a department of the UK Government formed in 1939 to co-ordinate the supply of equipment to all three British armed forces, headed by the Minister of Supply. There was, however, a separate ministry responsible for aircraft production and the Admiralty retained...
after conversion to 1XB standard. - Mk 1A F-BGNX, the fuselage of which is preserved at the de Havilland Aircraft Heritage CentreDe Havilland Aircraft Heritage CentreThe de Havilland Aircraft Heritage Centre, formerly the Mosquito Aircraft Museum, is a volunteer-run aviation museum in London Colney, Hertfordshire, England...
in HertfordshireHertfordshireHertfordshire is a ceremonial and non-metropolitan county in the East region of England. The county town is Hertford.The county is one of the Home Counties and lies inland, bordered by Greater London , Buckinghamshire , Bedfordshire , Cambridgeshire and...
, is the only surviving fuselage displaying the original "square" windows. The aircraft is currently under restoration.
Comet 2:
- Comet C2 Sagittarius serialUnited Kingdom military aircraft serialsIn the United Kingdom to identify individual aircraft, all military aircraft are allocated and display a unique serial number. A unified serial number system, maintained by the Air Ministry , and its successor the Ministry of Defence , is used for aircraft operated by the Royal Air Force , Fleet...
XK699, later maintenance serial 7971M, is displayed at the gate of RAF LynehamRAF LynehamRAF Lyneham is a Royal Air Force station in Wiltshire, England. It was the home of all the Lockheed C-130 Hercules transport aircraft of the Royal Air Force before they were relocated to RAF Brize Norton.The station was also home to No...
in WiltshireWiltshireWiltshire is a ceremonial county in South West England. It is landlocked and borders the counties of Dorset, Somerset, Hampshire, Gloucestershire, Oxfordshire and Berkshire. It contains the unitary authority of Swindon and covers...
.
Comet 4
- Comet 4 (Registration G-APDB), is on display at the Imperial War Museum DuxfordImperial War Museum DuxfordImperial War Museum Duxford is a branch of the Imperial War Museum near the village of Duxford in Cambridgeshire, England. Britain's largest aviation museum, Duxford houses the museum's large exhibits, including nearly 200 aircraft, military vehicles, artillery and minor naval vessels in seven...
, England. Long displayed outdoors in Dan-Air colours as part of the Flight Line Display, it is now in BOAC livery in the AirSpace building. - Comet 4B (Registration G-APYD) is stored at the Science Museum facility at WroughtonWroughtonWroughton is a large village in Wiltshire, England. It is part of the Borough of Swindon and is south of Swindon.-History:The earliest evidence of human presence in the area is from the Mesolithic period, although this is fairly limited...
, Wiltshire. - Comet 4C (Registration N888WA) is being restored and on display in BOAC livery at the Museum of FlightMuseum of FlightThe Museum of Flight is a private non-profit air and space museum at King County International Airport , south of downtown Seattle, Washington. It was established in 1965 and is fully accredited by the American Association of Museums...
, near Seattle. 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 4C (Registration G-BDIW) is on display at the Flugausstellung Leo Junior at HermeskeilHermeskeilHermeskeil is a town in the Trier-Saarburg district, in Rhineland-Palatinate, Germany. It is situated in the Hunsrück, approx. 25 km southeast of Trier...
, Germany in Dan-Air colours. - Comet 4C (Registration G-BDIX) is on display at the National Museum of Flight near EdinburghEdinburghEdinburgh is the capital city of Scotland, the second largest city in Scotland, and the eighth most populous in the United Kingdom. The City of Edinburgh Council governs one of Scotland's 32 local government council areas. The council area includes urban Edinburgh and a rural area...
, in Dan-Air livery. - Comet 4C (Registration SU-ALM and later G-BEEX) cockpit section only is on display at the North East Aircraft MuseumNorth East Aircraft MuseumThe North East Aircraft Museum is a volunteer-run aviation museum situated on the site of the former RAF Usworth/Sunderland Airport, between Washington and Sunderland, England. The museum has the largest aviation collection between Yorkshire and Scotland and houses over 30 aircraft and a wide...
, Sunderland, United Kingdom. - The last Comet to fly was Comet 4C Canopus (Serial XS235), which is kept in running condition at Bruntingthorpe AerodromeBruntingthorpe AerodromeBruntingthorpe Aerodrome and Proving Ground is a privately owned airport in Leicestershire near the village of Bruntingthorpe. It was opened as RAF Bruntingthorpe in 1942.- United States Air Force use:...
, where fast taxi runs are regularly conducted.
Civilian operators
- Aerolíneas ArgentinasAerolíneas ArgentinasAerolíneas Argentinas , formally Aerolíneas Argentinas S.A., is Argentina's largest airline and serves as the country's flag carrier. Owned in its majority by the Argentine Government, the airline is headquartered in the Torre Bouchard, located in San Nicolás, Buenos Aires...
ordered six Comet 4s in 1958 and they were delivered in 1959 and 1960, with a service introduction on 16 April 1959, between Buenos Aires and Santiago, Chile. Due to the loss of three aircraft, a replacement Comet 4C was bought in 1962. After being moved from international flights to domestic flights from 1966, the survivors were retired and sold to Dan-Air in 1971.
:
- Qantas Empire AirwaysQantasQantas Airways Limited is the flag carrier of Australia. The name was originally "QANTAS", an initialism for "Queensland and Northern Territory Aerial Services". Nicknamed "The Flying Kangaroo", the airline is based in Sydney, with its main hub at Sydney Airport...
leased seven different Comet 4 aircraft in the early 1960s mainly to operate the Sydney to Singapore route.
:
- Canadian Pacific AirlinesCanadian Pacific AirlinesCanadian Pacific Air Lines was a Canadian airline that operated from 1942 to 1987. It operated under the name CP Air from 1968 to 1986...
ultimately had none in operation. One Comet 1A aircraft crashed on delivery and another was cancelled.
(Ceylon):
- Air CeylonAir CeylonAir Ceylon was the flag carrier airline of Sri Lanka from 1947 until 1978, when it was replaced by Air Lanka.- History :...
East African CommunityEast African Community
The East African Community is an intergovernmental organisation comprising the five east African countries Burundi, Kenya, Rwanda, Tanzania, and Uganda. Pierre Nkurunziza, the President of the Republic of Burundi, is the current Chairman of the East African Community. The EAC was originally...
(Kenya, Tanzania, Uganda):
- East African AirwaysEast African AirwaysEast African Airways Corp. was an airline jointly run by three countries in East Africa: Kenya, Tanzania; and Uganda, which were then part of an East African Community. The airline was headquartered in the Sadler House in Nairobi, Kenya...
had two new Comet 4s delivered in 1960 and another delivered in 1962. Four other Comet 4s were leased from BOAC in the 1960s.
:
- AREA Ecuador had one Comet 4 delivered in 1966 that was used on services between Quito and Miami. In 1968, the aircraft was impounded at Miami and remained under legal custody until scrapped in 1978.
:
- EgyptairEgyptAirEgyptAir is the flag carrier airline of Egypt and a member of Star Alliance. The airline is based at Cairo International Airport, its main hub, operating scheduled passenger and freight services to more than 75 destinations in the Middle East, Europe, Africa, Asia, and the Americas...
inherited four surviving Comet 4Cs from United Arab Airlines in 1971 and sold these in the late 1970s. - MisrairEgyptAirEgyptAir is the flag carrier airline of Egypt and a member of Star Alliance. The airline is based at Cairo International Airport, its main hub, operating scheduled passenger and freight services to more than 75 destinations in the Middle East, Europe, Africa, Asia, and the Americas...
had two new Comet 4C delivered in 1960. The airline became United Arab Airlines in 1960. - United Arab AirlinesEgyptAirEgyptAir is the flag carrier airline of Egypt and a member of Star Alliance. The airline is based at Cairo International Airport, its main hub, operating scheduled passenger and freight services to more than 75 destinations in the Middle East, Europe, Africa, Asia, and the Americas...
inherited two Comet 4C from Misrair with seven new Comet 4Cs delivered in the 1960s. The airline became Egyptair in 1971.
:
- Air FranceAir FranceAir France , stylised as AIRFRANCE, is the French flag carrier headquartered in Tremblay-en-France, , and is one of the world's largest airlines. It is a subsidiary of the Air France-KLM Group and a founding member of the SkyTeam global airline alliance...
operated three new Comet 1A briefly in the 1950s before they were withdrawn. - Union Aéromaritime de TransportUnion Aéromaritime de TransportUnion Aéromaritime de Transport was a French airline. It had its head office in the 8th arrondissement of Paris.In addition, on 26 December 1958 a DC-6 of UAT crashed in Salisbury, Rhodesia ....
operated three new Comet 1As briefly in the 1950s, one was destroyed and two were withdrawn from service.
:
- Olympic Airways had four new Comet 4Bs delivered in 1960, operated in a pooling arrangement with BEA.
- Kuwait AirwaysKuwait AirwaysKuwait Airways is the national airline of Kuwait, with its head office on the grounds of Kuwait International Airport, Al Farwaniyah Governorate. It operates scheduled international services throughout the Middle East, to the Indian subcontinent, Europe, Southeast Asia and North America, from its...
operated one second-hand Comet 4 and two new Comet 4Cs in the 1960s.
:
- Middle East AirlinesMiddle East AirlinesMiddle East Airlines – Air Liban S.A.L. , more commonly known as Middle East Airlines , is the national flag-carrier airline of Lebanon, with its head office in Beirut, near Beirut Rafic Hariri International Airport...
:
- Malaysian Airways operated five second-hand Comet 4s in the 1960s. The airline became Malaysia-Singapore Airlines in 1966.
/ :
- Malaysia-Singapore AirlinesMalaysia-Singapore AirlinesMalaysia-Singapore Airlines came into being in 1966 as a result of a joint ownership of the airline by the governments of Malaysia and Singapore. The airline ceased operations after 6 years in 1972 when both governments decided to set up their own national airlines...
inherited five Comet 4s from Malysian Airlines in 1966 and two more Comet 4s in 1967 and 1968. All sold to Dan-Air London in 1969.
:
- MexicanaMexicana de AviaciónFounded in 1921, Compañía Mexicana de Aviación, S.A. de C.V. was Mexico's oldest airline, before ceasing operations on August 28, 2010. The group's closure was announced by the company's recently installed management team a short time after the group filed for Concurso Mercantil and US Chapter 15...
:
- Transportes Aereos PortguesesTAP PortugalTAP Portugal, commonly known as TAP, is the national airline of Portugal. It has its head office in Building 25 on the grounds of Portela Airport in Lisbon, and has been a member of the Star Alliance since 14 March 2005, the same day on which the company celebrated its 60th anniversary...
, between 1959 and 1962, chartered a British European Airways Comet 4B to operate a service between London and Lisbon.
:
- The Government of Saudi Arabia ordered a Comet 4C for use of King Saud bin Abdul AzizSaud of Saudi ArabiaSaud bin Abdul-Aziz Al Saud was King of Saudi Arabia from 1953 to 1964. He was removed from power by Faisal because of Saud's mismanagement and waste. He was the eldest surviving son of Ibn Saud and became Crown Prince in 1933. He died in exile in Greece.-Early life:Saud was born in 1902 in Kuwait...
. The Comet 4C was delivered in 1962 but crashed in 1963.
South Africa
- South African AirwaysSouth African AirwaysSouth African Airways is the national flag carrier and largest airline of South Africa, with headquarters in Airways Park on the grounds of OR Tambo International Airport in Kempton Park, Ekurhuleni, Gauteng. The airline flies to 36 destinations worldwide from its hub at OR Tambo International...
chartered two Comets from BOAC, 1953–1954.
:
- Sudan AirwaysSudan AirwaysSudan Airways is the national airline of Sudan, headquartered in Khartoum. The airline operates under the IATA airline designator SD and the ICAO airline designator SUD, while its callsign is SUDANAIR....
operated two new Comet 4Cs in the 1960s and early 1970s.
:
- BEA AirtoursBritish AirtoursBritish Airtours was a UK charter airline with flight operations out of London Gatwick and Manchester Airport.Originally established as BEA Airtours in 1969, it became a wholly owned subsidiary of then state-owned British Airways following the British European Airways — British Overseas Airways...
- British European Airways (BEA)British European AirwaysBritish European Airways or British European Airways Corporation was a British airline which existed from 1946 until 1974. The airline operated European and North African routes from airports around the United Kingdom...
- British Overseas Airways Corporation (BOAC)British Overseas Airways CorporationThe British Overseas Airways Corporation was the British state airline from 1939 until 1946 and the long-haul British state airline from 1946 to 1974. The company started life with a merger between Imperial Airways Ltd. and British Airways Ltd...
had a total of 10 Comet 1As delivered in the 1950s, with survivors withdrawn after the Cohen Inquiry findings. A total of 19 Comet 4s were delivered from 1957. - Channel AirwaysChannel AirwaysChannel Airways was a private airline formed in the United Kingdom in 1946 as East Anglian Flying Services.The newly formed airline initially operated aerial joy rides with a single, three-seater aircraft from an airstrip on the Kent coast...
obtained five Comet 4Bs from British European Airways in 1970 and these were re-configured to a high-density 109-seat configuration for the inclusive tour charters from the United Kingdom. One aircraft was retired in 1971 as life-experienced, the remainder were obtained by Dan-Air when Channel went into receivership in 1972. - Dan-AirDan-AirDan-Air was a leading private, independentindependent from government-owned corporations airline based in the United Kingdom....
also known as Dan-Air LondonDan-AirDan-Air was a leading private, independentindependent from government-owned corporations airline based in the United Kingdom....
bought all the surviving flyable Comet 4s from the late 1960s into the 1970s. Some were for spares reclamation but most were operated on the carriers inclusive tour charters; a total of 48 Comets of all marks were inventoried.
Military operators
Canada:
- Royal Canadian Air ForceRoyal Canadian Air ForceThe history of the Royal Canadian Air Force begins in 1920, when the air force was created as the Canadian Air Force . In 1924 the CAF was renamed the Royal Canadian Air Force and granted royal sanction by King George V. The RCAF existed as an independent service until 1968...
- 412 SquadronNo. 412 Squadron RCAFNo. 412 Transport Squadron of the Royal Canadian Air Force is one of 3 transport squadrons attached to CFB Trenton in Trenton, Ontario. This squadron, however, is based out of Ottawa, Ontario. It had formerly been attached to CFB Ottawa, which closed in 1994. The squadron operates with a strength...
(1953–1963) Comet 1A (later retrofitted to 1XB)
- 412 Squadron
:
- Royal Air ForceRoyal Air ForceThe Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...
- 51 SquadronNo. 51 Squadron RAFNo. 51 Squadron of the Royal Air Force most recently operated the Nimrod R1 from RAF Waddington, Lincolnshire until June 2011. Crews from No. 51 Squadron are currently training alongside the US Air Force on the Boeing RC-135, which is planned to enter service with the RAF over the next seven years...
(1958–1975) Comet C2, 2R - 192 SquadronNo. 192 Squadron RAFNo. 192 Squadron was a Royal Air Force squadron, operational during the First World War as a night training squadron, and during the Second World War as a radar countermeasure unit. After the war the squadron served again in the Electronic Intelligence role, until disbanded.-Formation in World War...
(1957–1958) Comet C2, 2R - 216 SquadronNo. 216 Squadron RAFNo. 216 Squadron of the Royal Air Force operates the Lockheed Tristar K1, KC1 and C2 from RAF Brize Norton, Oxfordshire.- History :216 Squadron was formed at RAF Manston by re-numbering No. 16 Squadron RNAS when the RAF was established in 1918, hence it is always spoken of as 'two-sixteen Squadron'...
(1956–1975) Comet C2 and C4
- 51 Squadron
- Royal Aircraft EstablishmentRoyal Aircraft EstablishmentThe Royal Aircraft Establishment , was a British research establishment, known by several different names during its history, that eventually came under the aegis of the UK Ministry of Defence , before finally losing its identity in mergers with other institutions.The first site was at Farnborough...
Cancelled orders
- British Commonwealth Pacific AirlinesBritish Commonwealth Pacific AirlinesBritish Commonwealth Pacific Airlines or BCPA, was an airline registered in New South Wales, Australia in June 1946 with headquarters in Sydney. It was formed by the governments of Australia , New Zealand and the United Kingdom to pursue trans-Pacific flights...
had placed various orders for Comets in the 1950s but the airline closed before any were delivered.
- Air IndiaAir IndiaAir India is the flag carrier airline of India. It is part of the government of India owned Air India Limited . The airline operates a fleet of Airbus and Boeing aircraft serving Asia, Australia, Europe and North America. Its corporate office is located at the Air India Building at Nariman...
:
- Panair do BrasilPanair do BrasilPanair do Brasil is a defunct airline of Brazil. Between 1945 and 1965 it was considered to be the largest carrier not only in Brazil but in all of Latin America.-NYRBA do Brasil :...
had one Comet 2 on order but did not take delivery.
:
- Japan Air Lines had three Comet 2s that were not completed. The airline originally ordered two aircraft in August 1952 and later increased the order to three, but the entire order was cancelled.
:
- Capital AirlinesCapital AirlinesCapital Airlines was an airline serving the eastern United States that merged into United Airlines in 1961. Its primary hubs were National Airport near Washington, DC, and Allegheny County Airport near Pittsburgh. In the 1950s it was the largest US domestic carrier after the Big Four . Its...
ordered the Comet 4 in July 1956 which were to be supplemented by 10 Comet 4As, a variant modified for Capital. Following financial problems and the takeover by United Airlines, the order was cancelled. - National AirlinesNational Airlines (NA)National Airlines was an airline founded in 1934 and was headquartered on the grounds of Miami International Airport in unincorporated Miami-Dade County, Florida, United States near Miami.- History :...
ordered 12 aircraft, a mix of Comet 2s and Comet 3s in October 1953. The order was cancelled. - Pan American Airlines ordered three Comet 3s in October 1952 with options on a further seven. The order was cancelled.
:
- Linea Aeropostal Venezolana had two Comet 2s on order that were not completed.
Accidents and incidents
Date from Jet Airliner Production List (1992)- 26 October 1952: BOAC Comet 1 G-ALYZ crashed on takeoff from Rome-Ciampino Airport, Italy.
- 3 March 1953: Canadian Pacific Airlines Comet 1 CF-CUN stalled on takeoff at Karachi, Pakistan. This was the first fatal accident involving a jet airliner.
- 2 May 1953: BOAC Comet 1 G-ALYV crashed near Calcutta, India.
- 25 June 1953: Union Aeromaritime de Transport Comet 1 F-BGSC skidded off a runway at Dakar, Senegal, damaged beyond repair.
- 16 July 1953: A BOAC Comet landed at Juhu AerodromeJuhu AerodromeJuhu Aerodrome an airport serving Mumbai, was India's first civil aviation airport. It is currently used by small private aircraft and as a heliport....
instead of Santacruz Airport, Bombay. The aircraft was flown out some eight days later. - 10 January 1954: BOAC Flight 781BOAC Flight 781On 10 January 1954, British Overseas Airways Corporation Flight 781 a de Havilland DH.106 Comet 1 registered G-ALYP, took off from Ciampino Airport in Rome, Italy, en route to Heathrow Airport in London, England, on the final leg of its flight from Singapore...
crashed into the sea south of Elba, Italy. - 8 April 1954: South African Airways Flight 201South African Airways Flight 201South African Airways Flight 201, a de Havilland Comet 1, took off at 18:32 UTC from Ciampino Airport in Rome, Italy en route to Cairo, Egypt, on the second stage of its flight from London to Johannesburg, South Africa. The flight crashed, killing all aboard at around 19:07 UTC on 8 April 1954...
(chartered from BOAC) crashed into the Tyrrhenian SeaTyrrhenian SeaThe Tyrrhenian Sea is part of the Mediterranean Sea off the western coast of Italy.-Geography:The sea is bounded by Corsica and Sardinia , Tuscany, Lazio, Campania, Basilicata and Calabria and Sicily ....
north of Stromboli, Italy. - 13 September 1957: No. 192 Squadron RAFNo. 192 Squadron RAFNo. 192 Squadron was a Royal Air Force squadron, operational during the First World War as a night training squadron, and during the Second World War as a radar countermeasure unit. After the war the squadron served again in the Electronic Intelligence role, until disbanded.-Formation in World War...
Comet 2R XK663 damaged beyond repair in a hangar fire. - 27 August 1959: Aerolíneas Argentinas Comet 4 LV-AHP flew into a mountain on approach to Asunción, Paraguay.
- 20 February 1960: Aerolíneas Argentinas Comet 4 LV-AHO was damaged beyond repair in a heavy landing at Buenos Aries-Ezeiza, Argentina.
- 23 November 1961: Aerolíneas Argentinas Flight 322Aerolineas Argentinas Flight 322Aerolíneas Argentinas Flight 322 was a scheduled Buenos Aires–São Paulo–Port of Spain–New York City international passenger service, operated with a Comet 4, registration LV-AHR, that crashed during climbout on the early stages of its second leg, when it collided with tree tops shortly after...
hit a tree on takeoff at São Paulo/Campinas-Viracopos, Brazil. - 21 December 1961: British European Airways Comet 4 G-ARJM crashed on takeoff from Ankara, Turkey.
- 19 July 1962: First United Arab Airlines Flight 869 crashed into a mountain 100 km northeast of Bangkok, Thailand.
- 20 March 1963: Saudi Arabian Government Comet 4C SA-R-7 crashed in the Italian Alps near Cuneo.
- 28 July 1963: Second United Arab Airlines Flight 869United Arab Airlines Flight 869 (1963)United Arab Airlines Flight 869 was an international scheduled passenger de Havilland Comet 4C flight from Tokyo, Japan to Cairo via Hong Kong, Bangkok, Bombay and Bahrain. On 27 July 1963 it was being operated by a de Havilland Comet registered as SU-ALD, when on approach to Bombay - Santa Cruz...
crashed into the sea near Bombay, India. - 22 March 1964: Comet 4 G-APDK on lease to Malaysian Airlines, was damaged beyond repair landing at Singapore.
- 12 October 1967: Cyprus Airways Flight 284Cyprus Airways Flight 284Cyprus Airways Flight 284 was a de Havilland Comet that broke up during a flight to Nicosia International Airport on 12 October 1967, after an explosive device detonated in the cabin. The airliner crashed in the Mediterranean Sea and all 66 passengers and crew on board died.-Aircraft:The aircraft...
damaged by an inflight bomb explosion, crashed in the Mediterranean SeaMediterranean SeaThe Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
off the Turkish coast. - 28 December 1968: Middle East Airlines Comet 4Cs OD-ADQ and OD-ADR both destroyed by Israeli troops in an attack at Beirut, Lebanon.
- 14 January 1970: United Arab Airlines Comet 4 SU-ANI crashed at Addis Ababa, Ethiopia.
- 9 February 1970: United Arab Airlines Comet 4 SU-ALE crashed after takeoff near Munich, West Germany.
- 3 July 1970: Dan-Air Comet 4 G-APDN flew into the Montseny mountains, northwest of Barcelona, Spain.
- 7 October 1970: Dan-Air Comet 4 G-APDL damaged beyond repair after a wheels-up landing at Newcastle Airport, England.
- 2 January 1971: United Arab Airlines Comet 4 SU-ALC Flight 844 crashed near Tripoli Airport, Libya.
Specifications (Comet 4)
See also
External links
- "DH Aircraft" pages about the DH-106 including X-Plane simulation model
- Accidents involving De Havilland Comet
- Marc Schaeffer's Comet Website
- Campaign to return Canopus to flight
- National Geographic Episode of "Seconds from Disaster" on the crashes of 1954
- The de Havilland Comet in RCAF Service
- History of the world's first Jetliner
- "The Tale of the Comet" a 1952 Flight article on the design and development of the Comet
- "B.O.A.C. Comet Lost: Services Suspended," a 1954 Flight news item announcing the loss of Comet G-ALYP
- "Elba Accident Developments," a 1954 Flight news item on further developments on the accident
- http://www.flightglobal.com/pdfarchive/view/1954/1954%20-%200279.html"Series 2 Comet in Africa," a 1954 Flight article on the Comet including breaking news on the Elba accidentBOAC Flight 781On 10 January 1954, British Overseas Airways Corporation Flight 781 a de Havilland DH.106 Comet 1 registered G-ALYP, took off from Ciampino Airport in Rome, Italy, en route to Heathrow Airport in London, England, on the final leg of its flight from Singapore...
] - "Comet Enquiry: The First Week," a 1954 Flight article reporting the enquiry into the Comet design
- "Comet Enquiry: The Fourth Week," a 1954 Flight article reporting the enquiry into the Comet design
- "The Comet Accidents: History of Events," a 1954 Flight article of Sir Lionel Heald's summary of the enquiry
- "Report of the Comet Enquiry" a 1955 Flight article reporting the publishing of the enquiry into the Comet design
- "Tank Test Mk 2," a 1955 Flight article on the use of water tank pressure and fatigue testing of the Comet 2 cabin