Aviation Classic: De Havilland Comet – Britain Pushes Aviation Boundaries, Maybe A Bit Too Far


(first posted 9/25/2016)   The first jetliner in the world wasn’t a Boeing or a McDonnell Douglas. It was a government sponsored project, conceived in war to serve a post-war Empire. It was a commercial failure, not helped by a fundamental flaw that made it the first jetliner to crash and be grounded. It conceded market supremacy to the Americans who weren’t then challenged from Europe for half a century. But it was an aerodynamic beauty from the company that created the wooden Mosquito, and it had a life of 60 years. It looked and flew like no plane before it, and had a great name – Comet.

by Walter Stoneman, bromide print, 1944

The Comet had its roots in the British government’s wartime planning for the post war world – as early as 1942, the Air Ministry established a committee led by aviation pioneer and government minister John Moore-Brabazon, 1st Baron Brabazon of Tara, to consider how to meet future civilian aircraft needs.


Brabazon’s Committee recommended that  six types of civilian aircraft be developed, ranging from a large, luxurious airliner capable of serving the transatlantic market to a ten seat plane for low volume domestic routes. The resulting designs were a mixed bunch. The large Bristol Brabazon was a flop – only one prototype was built. The economics of a plane the size of a Boeing 767 but with just  100 seats were as weak as the design was over-ambitious.


On the other hand, the de Havilland DH104 Dove, with two engines and around 10 seats, used modernity, with modern engines and easy maintenance, to give it an edge over the many surplus military transports that became available after the war.


Alongside the Brabazon Committee, the British engineer Frank Whittle was slowly perfecting his jet engine, and just as slowly persuading the RAF and government of its merits.


By 1942, the RAF had ordered what became the de Havilland Vampire as one of two prototype fighters using the new technology – and its success gave Brabazon committee member Geoffrey de Havilland the confidence to push the committee to include a specification for a 100 seat pressurised jet powered airliner, aiming for a cruising speed of 400 mph (640 km/h).

De Havilland was convinced his company could produce a plane meeting the resulting specification, and, determined to get ahead of his competitors, stuck to his guns. And, in February 1945, the British government duly gave de Havilland the contract to develop what became the Comet; by December the state owned British Overseas Airways Corporation (BOAC) had ordered 10, and a design team began work in 1946 – all without any publicity.


In 1949, the Comet emerged from its hitherto secret development, looking like this. Let’s think about this for a moment. Just four years earlier, Europe had emerged from the bloodiest war in its bloody history; across Britain, factories were struggling to move from swords to ploughshares, while coping with significant bomb damage and dislocation, and with funds short. The country was basically broke and dependent on American credit; food and petrol were rationed, coal was scarce, infrastructure was crumbling from wartime overuse and under maintenance, and the new threat of Russian dominance of eastern Europe was becoming apparent just as a huge army was being demobilised and returned to civvy street. And in the middle of this, a sleek streamlined silver plane, powered by a technology that had barely existed five years earlier, shot across the sky, promising a better future for us all. It would be fair to call the public gobsmacked.


As it appeared in 1949, the Comet 1 was like no other plane. The streamlined fuselage, which still looks modern now, made extensive use of new alloys and adhesives in the metal skin, while the swept back wings with the engines buried in the wing root marked a transformation in appearance from any propeller driven plane.


The design was all de Havilland’s, led by Ronald Bishop (1903 – 1989), a 25 year de Havilland veteran and also chief designer of the Mosquito.


The Comet 1 was 93ft long, with a wingspan of 115ft. De Havilland’s Goblin jet engines, developed from the Vampire’s, were also fitted to the Comet 1, until Rolls-Royce’s new Avon jets (an evolution of the Goblin) were ready. A lot of the visual impact of the Comet comes from how the jets were buried in the wing root; this location was partly for aerodynamics, and partly to avoid overloading the wings with the heavy engines. It did however necessitate extensive noise and heat insulation, and complicated the structure of the wings and the protection needed from any engine explosion.


First BOAC flight leaves London Heathrow

First flight was on 27 July 1949, flown by the famous de Havilland test pilot John Cunningham, with Frank Whittle watching from the ground. The first production aircraft flew in January 1951, and by May 1952 BOAC were ready for fare-paying passengers – the world’s first on a jetliner. The first route was not transatlantic – the range of the Comet was not yet sufficient for this – but to Johannesburg, South Africa, with en route stops at Rome, Beirut, Khartoum (Sudan), Entebbe (Uganda) and Livingstone (Zambia) – a distance of 7,000 miles in 23 hours, over 4 hours faster than the previous piston engine service, and with a far superior passenger experience, and cruising at 450mph.


In BOAC configuration, it had 36 reclining seats, with legroom to match, and service unlike anything you’ll see today.


By the summer of 1953, BOAC Comets were also reaching India, Colombo (Sri Lanka), Singapore and Tokyo, as well as Australia.  French airlines flew it to the West Indies, and the larger Comet 2 was being developed, and even the Americans were placing orders.


But then it all began to go wrong.


The first accident was in October 1952, on take-off from Rome airport, and was blamed on pilot error. Another in March 1953, on take-off from Karachi in Pakistan, was ascribed to the same cause.  But with hindsight, that perhaps wasn’t the full story.

A BOAC Comet was lost near Kolkata, India, in May 1953 (a year to the day after the first passenger flight) – reports spoke of a wingless plane plunging to the ground, and the first suspicions of structural weakness were beginning, but were linked to turbulence rather than any other cause.


But in January 1954, again shortly after take-off from Rome,  the first production Comet crashed into the Mediterranean  near the island of Elba, killing all 35 on board. It could no longer be denied that a serious problem existed. De Havilland made 60 modifications in a bid to keep the plane flying, but BOAC grounded its Comet fleet, and the Royal Navy was sent to recover the wreckage.


Then, in April, another Comet, chartered by BOAC to South African Airways, crashed near Naples, killing 21. This was the end. Production was halted, all Comets grounded worldwide, the UK Certificate of Airworthiness revoked, and a public inquiry established. As this was before the days of voice and data recorders, only the wreckage could provide clues to the cause.


Eventually, over 60% of the Comet from the January 1954 crash was recovered and reassembled.


Water tank testing at the de Havilland site at Hatfield, near London, identified that the fuselage had burst open at the corner of one of the Comet’s distinctive large square windows. Further tests on a second airframe donated by BOAC produced the same result, at the corner of a hatch. Metal fatigue in the ground-breaking alloys through the exaggerated stresses at the corners was thus pinpointed. Problems were exacerbated by the faster pressurisation and depressurisation cycles of a fast high flying jet compared to those of existing piston engine planes.


Comet 1 mothballed at de Havilland, Hatfield

Today, such a weakness would probably be the end of a plane, with its reputation decisively shredded. But not the Comet. All the remaining Comet 1s were scrapped, and the Comet 2s that were in production were modified with heavier gauge skin and smaller, round windows before being passed to the RAF rather than their intended civil purchasers.


There was a Comet 3, which was already in development by early 1954; it was a lengthened version of the Comet 2, offering greater range and capacity. But it never entered service, as the fuselage was based on the flawed Comet 2.


In place of the Comet 2, airlines got the Comet 4 from 1958 – the definitive Comet, and the first jetliner capable of transatlantic flight.


The Cornet 4 came in three versions, all with Rolls-Royce Avon jets.  The original Comet 4, 18 feet longer than the Comet 1, took up to 81 passengers in a lengthened and strengthened fuselage; the 4b had a longer still fuselage, with shorter wings optimised for short haul flights – launch customer was BEA (British European Airways – the other half of what became British Airways in 1974). The 4c took the longer fuselage of the 4b and the longer wings of the 4 to make the final version; 23 examples were built, mostly sold to airlines in central America and the Middle East. In total, 113 Comets of all types were built


So, on 4 October 1958, BOAC inaugurated the first transatlantic jet service, between London and New York, with Comet 4’s seating 48 passengers in space and comfort.  Westbound, with a stop in Gander, Newfoundland, took 10 hours 22 minutes; eastbound, non-stop, 6 hours 11 minutes with helpful tailwinds – impressive even now. But on October 26, Pan-Am began a competing service with the new Boeing 707 – and the writing was on the wall for the Comet. The American jet was bigger, more fuel economical and available in much larger quantities than de Havilland could manage – and hearing Boeing talk about how the Comet’s problems had influenced their thinking was scant consolation for the Brits.


The Boeing was developed from the 367-80 prototype, which first flew in 1954 – 5 years behind the Comet, and it showed in  the design. The Boeing’s swept wings, with four jets hanging from them in pods, looked more modern than the Comet’s straighter wings, and the greater length (148 feet to the Comet 4’s 111ft) and wider fuselage allowing 6 abreast seating gave a larger and thus more profitable capacity of up to 189 passengers. This was clearly the model for future long distance air transport, not the small and lightly loaded Comet. By 1979, Boeing had built over 1,000 707s and McDonnell-Douglas over 500 of the very similar DC-8.


Hedging their bets early on, BOAC had ordered fifteen 707s back in 1956, and by 1960, was flying the 707-420, fitted with Rolls-Royce Conway 508 engines, the world’s first bypass turbofan jets, rather than the typical Pratt and Whitney jets.


BOAC promoted them as the “Rolls-Royce 707”, playing up the British engines. BOAC’s last Comet left the fleet in 1965 and soon disgruntled British engineers spoke about the ‘Boeing Only Aircraft Corporation’.


Other British airlines kept their Comets for longer, notably the British charter operator Dan Air. All of Dan Air’s 44 Comets (although the fleet never exceeded 18 airworthy craft) were second hand, including several from the RAF. The air force had been a user of Comets since 1956, for troop and VIP transport, and for general transport duties. Well maintained aircraft with low usage obviously appeal to charter airlines and Dan Air snapped up the last few when the Air Force declared them surplus in 1976.


With strengthened floors and reduced seat pitch, Dan Air squeezed in 119 seats in rows five abreast into their Comets, but the plane’s days were numbered – a Comet with 119 passengers used the same fuel as a DC-10 with 345. Dan Air operated the Comet 4c until 1980 – being the last operator of the world’s first jet is probably the only thing Dan Air can be positively remembered for!


But there was more to come. The Comet 4 fuselage provided the base for the Hawker Siddeley Nimrod maritime reconnaissance plane (Nimrod, Comet, Spitfire, Mosquito, Lightning, Hurricane, Vulcan – we Brits know how to name planes!).  Designed to replace the Avro Shackleton (itself a development of the Lancaster), and powered by Rolls-Royce Spey jets, the Nimrod first flew in 1967.


The Nimrod provided Britain’s anti-submarine warfare and maritime reconnaissance capability, including search and rescue, for almost 40 years, until the planes were prematurely retired as part of swingeing defence cuts that also claimed the Hawker Harrier. They were key to the RAF’s role in the Falklands War of 1983, by providing reconnaissance and radar based navigation support to the Vulcans and Victors that were used to attack the islands’ airport.


The first two Nimrods were actually built from unfinished Comet airframes; the Spey jets gave greater fuel efficiency, and the plane was designed to allow cruising on just two engines to extend its range and endurance even further.


But after the Comet, Britain never challenged Boeing and McDonnell Douglas again head-on – subsequent British jetliners were short haul planes like the BAC111 and the Hawker Siddeley Trident. The last British long haul jet was the Vickers VC-10, which was specifically designed to serve Commonwealth routes, principally between Britain and Africa with short runways at high altitude. Not until the Airbus consortium was formed in the 1980s did the Americans face real competition.


Several Comets remain; Duxford near Cambridge has G-APDB in BOAC livery, the first jetliner to cross the Atlantic, while the Scottish National Museum of Flight at East Fortune, 30 miles outside Edinburgh, has G-BDIX, still in Dan Air colours. It may look a bit tired and in need of a repaint –but that would cover up the RAF markings still visible on the rear fuselage!


Stepping inside it will give away its age – the door is barely 5ft 6in high, the front door is on the right, not the now universal left, and the luggage racks are racks, not lockers. This is the four man cockpit.

This one is a Comet 4c, named Canopus, and the last to fly, in 1996, after spending its entire 33 year life as a Ministry of Defence research plane. It still taxis at Bruntingthorpe Aerodrome in the English Midlands, alongside a collection of Cold War jets.


The Nimrod was shot at the also excellent Yorkshire Air Museum, on a former Bomber Command base outside the city of York;  the Museum will tell you that manned flight was invented in Yorkshire, by George Cayley – and they have a case! And you might enjoy reading Empire of the Clouds, a very readable history of 1950s British jet aviation.

800px-de_havilland_comet_pic_1_rejsRAF Museum, Cosford

So there you have the Comet – too far too soon, perhaps, then a refusal to let disaster and failure prevent pioneering triumphs and ending with almost 60 years’ service? Not bad for a first effort at a jetliner? The jury is still out, I suspect.