Tuesday, 1 April 2025

Every Jetliner Ever Made: de Havilland and Sud

Let's have a look at Every Jetliner Ever Made. In alphabetical order, but with Airbus and Boeing at the end just to make things real spicy-like. Today we're going to look at de Havilland of Great Britain and Sud-Aviation of France. The two companies only produced one jetliner apiece, the de Havilland Comet and the Sud-Aviation Caravelle, but they were two of the very first to enter service, first in the case of the Comet. They were developed in parallel, like brother and sister, and even used some of the same components.

All aircraft are borne of a dream. The Comet and the Caravelle were borne of the post-war dreams of Britain and France. In 1945, at the end of the Second World War, the two countries still possessed huge colonial empires, but their sun was setting.

Nonetheless Britain and France still hoped to retain their place at the top table, so the two countries developed nuclear weapons, and rockets, and front-wheel-drive cars, and motorways, and jet airliners. On one level the Comet and the Caravelle were very successful. The Comet was the first ever jetliner to enter revenue service and the first to carry paying passengers across the Atlantic while the Caravelle was an influential sales hit that remained in service into the twenty-first century. But the Comet was beset by technical problems, and the Caravelle was quickly overtaken by competition from Boeing and Douglas, and ultimately the two aircraft outlasted their parent companies.

I realise that in the last article I said I would write about Douglas. The problem is that I have trouble with letters. It makes sense that twelve comes after four because twelve is larger. But why should O come after E? Why?

de Havilland (Great Britain)

Lower case de, then Havilland with two Ls. de Havilland was named after Geoffrey de Havilland, a talented engineer who founded the company in the early 1920s after being discharged from war service with the RFC. In the inter-war years de Havilland established its reputation with the Tiger Moth trainer, and also the Dragon series of airliners. During the Second World War the company was responsible for the high-speed Mosquito fighter-bomber-reconnaissance aircraft, and by the end of the war it was deep in development of one of Britain's first jet fighters, the Vampire.

A de Havilland Dragon Express

There's something poignant about de Havilland. The man lived long enough to see two of his three children killed in accidents while test-flying the company's own aircraft. The jetliner that was supposed to secure de Havilland's post-war future - the Comet - ended up killing the company, which was absorbed into Hawker-Siddeley in 1960. de Havilland himself passed away five years later. He was one of those early aviation pioneers who was born in the days before heavier-than-air flight. He lived long enough to not only see the jet age but to help create it. de Havilland's Canadian subsidiary, de Havilland Canada, still exists as an independent entity, but it's one of those resurrected brand names that has very little in common with the original.

I'm going to digress here. Even before victory in the Second World War was assured the British government was worried about the post-war future of civil aviation. There was a risk that Britain would end the war with an enormous aviation industry that could only produce obsolete piston-engined bombers. And so in 1942 the government asked a chap called Lord Brabazon to form a committee and sort things out. Lord Brabazon's real name was John Moore, but he liked to call himself Lord Brabazon because it commanded respect.

In the short term the committee believed that Britain's immediate post-war needs could be met with conversions of bomber aircraft, of which Britain had no shortage. It sounded good in theory, but the results were disappointing. Piston-engined bombers had lots of engine power but very little internal space. The Avro Lancaster could, in theory, lift the weight of around sixty passengers, but the fuselage was so narrow that the airliner conversion, the Lancastrian, only had room for around nine people, who had to sit sideways and wear oxygen masks. The Avro York, which was considerably more advanced than the Lancastrian, had twice the passenger load, but it was still less fuel-efficient than the popular Douglas DC-3. Nowadays the Lancastrian is only remembered for its poor accident record while the York isn't remembered at all.

An Avro Lancastrian

The Brabazon Committee's other solutions were hit-and-miss. The smaller, short-ranged designs struggled to sell in the face of a post-war glut of Douglas DC-3s. The giant Bristol Brabazon luxury propliner never entered series production, but the turboprop-powered Vickers Viscount and Bristol Britannia were popular enough. By the time Geoffrey de Havilland joined the committee his company was working on what would become the Vampire jet fighter, so he suggested a pure jet airliner, initially a fast mailplane, latterly a regular airliner. In 1942, when the Committee first met, the few jet-powered aircraft were prototypes, but by 1945 their effectiveness had been proven in combat.

Beyond their high thrust, jet engines have some big advantages over piston engines. They're more efficient at high altitude, at heights where piston engines run out of puff. They can cruise above the weather, which does wonders for timekeeping. They have fewer moving parts, or at least fewer reciprocating parts, which makes for smoother operation and in theory greater reliability, although it took an awful lot of work to develop turbine blades that could cope with the high temperatures of jet operation. Propellers generate draggy vortices when the tips approach supersonic velocity, which limits their top speed, but the enclosed blades of jet turbines can rotate much faster.

Early jets had some disadvantages - high fuel consumption, slow throttle response, a tendency to ice up - but those problems were rapidly solved. Nonetheless the high altitudes that commercial jets were expected to operate remained a major issue. At 40,000 feet an airliner's fuselage would have to be pressurised, which was a new technology in the 1940s. The pre-war Boeing 307 had a pressurised cabin, but it only flew at an altitude of 20,000 feet. The new breed of jetliners would fly much higher than that.

de Havilland came up with a number of design concepts, which eventually coalesced into a futuristic-looking swept-wing aircraft with four jet engines buried in the wing roots. de Havilland's team started work on the Comet in 1946, under a chap called Ronald Bishop, who had been responsible for the Mosquito. The original plan was for a super-futuristic tailless aircraft with a highly-swept wing, but erring on the side of caution Bishop eventually picked a more conventional design, powered by de Havilland Ghost turbojets. At first the Comet was envisaged as a mailplane with a tiny passenger load, but during development it grew and grew, until the eventual configuration had four engines buried in a low-mounted wing, with a passenger load of around forty people in a two-by-two arrangement.

The first prototype flew in 1949, with limited entry into service in 1952. The launch customer was BOAC, the state-owned airline. The Comet 1 didn't have the range to cross the Atlantic, so at first it serviced what remained of the British Empire. It flew around 44 passengers from London, via Rome, via Cairo, on to Johannesburg, or alternatively off to Tokyo and Hong Kong via what was then Bombay. Flight times from London Airport (now Heathrow) to Rome were around two and a half hours, surprisingly similar to modern schedules. In contrast BOAC's Lockheed Constellations took around five and a half hours on the same route, with a stop at Frankfurt for fuel.

As a generation one product the Comet had a curious mixture of old and new features. The cockpit had a fourth seat for a dedicated radio operator, who also operated the navigational equipment, which included a sextant periscope so that the flight might navigate by the stars. Fuel consumption was such that most of the initial routes were shuttle affairs, with multiple stops en route to the final destination, rather than direct there-and-back flights. Today it takes around fourteen hours to fly from London to Tokyo, but in 1953 BOAC's Comets took almost two whole days, taking off at 10:00 on Monday and arriving at 06:30 on Wednesday. It's not so much that the Comet was slow - although the cruising speed of 450mph was around 100mph less than modern airliners - but that it had to keep stopping for fuel every 1,500 miles or so.

In contrast BOAC's Merlin-powered Argonauts took twice as long. By the time the Comet had touched down in Tokyo, the Argonaut's passengers had only reached Rangoon. At that point they faced another day in the air, plus a night stop at Hong Kong, and then a final leg to their destination. I have no idea how much it would have cost to fly long-range on a Comet. This chap suggests that that a late-1940s BOAC ticket from London to Tokyo would have been the equivalent of £14,000 in modern money, versus around £800 or so for the same flight nowadays. The high cost of the tickets and the glamorous, far-off destinations - Rome, Beirut, Singapore - led to the media stereotype of a Jet Set, wealthy socialites who could afford to fly first-class to parties across the world. For a year or so Comet operations proceeded as normal and all was well with the world.

By modern standards the Comet's development cycle was extraordinarily rapid, from rough paper concept to service in just six years. Nonetheless de Havilland took great pains to ensure that it would work first time. There were worries that embedding the engines together in the wings would be a fire hazard, so the engines were surrounded with fireproof bulkheads and armoured panels. Pressurisation was also a major worry. In the words of Popular Mechanics, writing in 1950, "there can be no taking of chances on sudden failures that might cook or quick-freeze the customers in a jet liner or expose them precipitately to oxygen starvation by a cabin 'puncture' at 40,000 feet". And so de Havilland tested the fuselage in a water tank and designed the Comet's skin to withstand more than twice the expected loads.

A former RAF Comet 2

There were particular worries about the square windows, but de Havilland reinforced the surroundings and rounded off the corners, and despite urban legend the cabin windows themselves were never a particular problem. Metal fatigue was however a major concern, in part because of Nevil Shute's No Highway, an early techno-thriller published in 1948. It was filmed in 1951 as No Highway in the Sky, starring James Stewart as an engineer who believed that a new jetliner had a much shorter fatigue life than expected. de Havilland used a mixture of state-of-the-art adhesives and riveting techniques to ensure that the fuselage was flexible enough to remain intact through thousands of pressure and temperature cycles. The flush-with-the-nose cockpit windows were controversial on account of their poor downwards visibility, but in practice practice pilots managed.

Nonetheless there were fears that BOAC and de Havilland and the British government were pushing too hard. The Comet suffered two high-profile crashes in 1952 and 1953. The first, in October 1952, took place during take-off from Rome's Ciampino Airport. The pilot lifted the nose too quickly, causing the wings to act like giant airbrakes. The airliner ran off the end of the runway and was wrecked, albeit with no major injuries. The crash was blamed on the pilot, although nowadays most sources cite hard-to-read avionics and immature operating procedures. From the 1960s onwards the international aviation authorities began to use a system of V-speeds to determine when a pilot should lift the nose or abort take-off, but in 1952 pilots were expected to judge take-off by the seat of their pants, which was untenable in the new age of large, high-speed jet airliners.

The Comet's first fatal accident was in March 1953, during a night take-off from Karachi. The aircraft had been purchased by Canadian Pacific Airlines and was on a ferry flight. Again the airliner failed to take off, but this time it hit a ditch and burst into flames, killing all eleven occupants. The pilot was blamed for the accident, but in addition de Havilland took the opportunity to modify the wing design to generate more lift during high angles of attack.

Worst still was a third crash two months later, during which a Comet broke up a few minutes after take-off from Calcutta. Once again blame was heaped on the pilot, who had apparently overstressed the wings while flying through severe turbulence. In response to this accident de Havilland added a control damping system to smooth out the control forces. One month later a fourth Comet, flown by Air France, was written off after a hard landing at Dakar, although fortunately no-one was seriously hurt.

A Douglas DC-6

There were fears in the press that the Comet was jinxed, but it has to be borne in mind that the Comet was not the only contemporary airliner to encounter problems shortly after entering service. In 1947 the brand-new Douglas DC-6 suffered a pair of in-flight fires caused by a poorly-designed fuel tank vent, one of which resulted in the deaths of all on board, and a year later another DC-6 crashed with all hands when the crew were incapacitated by the aircraft's fire extinguishers. A few years later the turboprop-powered Lockheed Electra also had a disastrous launch when two aircraft broke up in flight within the space of a few months, caused by harmonic flutter brought on by weak engine mounts.

But the Comet was supposed to be a fresh start, and things got worse. "Not since the great ship Titanic went down had the British people felt such a stunning blow to their pride as masters of transport", wrote LIFE in January 1954. Earlier in the month a BOAC Comet had crashed into the sea a few minutes after an early-morning takeoff from Rome.

This time there was no turbulence. The aircraft, which had already logged a million miles of trouble-free passenger service, had suddenly broken up in flight, mid-way through an innocuous radio communication. It was baffling. The Comet was grounded pending an investigation, during which the Royal Navy undertook the painstaking task of raising the scattered wreckage from the sea bed. The investigation tentatively suggested that engine failure might have punctured the pressurised fuselage, so de Havilland took the opportunity to reinforce and overhaul the Comet's airframe.

The Comet returned to service in March 1954, which seems unusually hasty from a modern perspective. The original investigation was still in progress, but the prevailing attitude was that the first few accidents had been the result of pilot error, and the in-flight breakup had been a one-off. Furthermore air travel was just less safe in the 1950s than it is today. Between 27 July 1949, when the Comet's prototype first flew, and April 1954, when it was grounded for the second time, various models of the Lockheed Constellation were involved in no less than ten fatal accidents, killing hundreds.

Unfortunately just seventeen days after the aircraft re-entered service another Comet crashed into the sea. Again, the weather was fine, and there were no indications from the pilot that anything was amiss, but something was obviously very wrong.

By that point two-thirds of the wreckage of the previous disaster had been assembled into a framework of the doomed airliner. Examination of the recovered bodies revealed that many of the passengers had been killed after sustaining blows to the head, which suggested they had been sucked upwards out of their seats and dashed into the cabin ceiling.

A mixture of careful analysis of the wreckage and a multi-thousand cycle pressurisation test in a special water tank finally revealed the cause of the Comet's downfall. It wasn't the engines, or sabotage, or even the passenger cabin windows. Instead a tear had opened up alongside one of the ceiling-mounted navigation apertures. At altitude the tear had immediately ripped along the top of the fuselage, separating the nose from the rest of the aircraft, causing the remaining airframe to rapidly disintegrate due to the aerodynamic stresses. The passengers and crew had almost certainly died in less than a second.

On the positive side the enquiry had, finally, got to the bottom of the Comet's problems, although there were still some loose ends. During development de Havilland had subjected their test fuselage to a high-pressure proof test that should, by rights, have ruptured the fuselage, but the airframe had survived unscathed, and the earlier fatal crash at Calcutta, which had been blamed on turbulence, was never reinvestigated. But the Comet was given a clean bill of health once more, and although it went on to suffer several fatal accidents in years to come none of them were the result of a design flaw.

Unfortunately for de Havilland the crashes ruined the Comet's long-term prospects. From 1954 to 1958 the Comet sat idle while Boeing and Douglas of the United States designed their own jetliners, which entered service shortly thereafter. The original Comet 1 models were either scrapped as part of stress testing or upgraded to Comet 2 standard, with a thicker fuselage and more powerful engines. The Comet 2 itself was only ever operated by the RAF, as a VIP transport and signals intelligence aircraft. The Comet 3 had more powerful engines and distinctive wing-mounted fuel tanks, but only two examples were ever constructed, as testbeds.

The ultimate commercial Comet was the Comet 4, which was produced in three models. The standard Comet 4 had the Comet 3's wing-mounted tanks, with the fuselage stretched to fit around 80 seats, almost twice as much as the original. It had the range ot cross the Atlantic, although the flight still required a refuelling stop at Gander. The 4B and 4C were stretched even more, with and without wing-mounted tanks respectively.

On paper the Comet 4 was a worldbeater. It was the first airliner to offer transatlantic passenger service, with service beginning in October 1958. But just a few weeks later Pan-Am introduced the larger, longer-range Boeing 707 on the same route, carrying 174 passengers versus the Comet's 80. The Comet 4 sold to a surprisingly large number of airlines, mostly in Africa, South America, and the Far East, although the orders tended to be for one or two aircraft at a time. BOAC themselves only used the Comet for two more years before replacing it with the Boeing 707. By that time the Douglas DC-8 had entered service, and between them the 707 and the DC-8 were the future, not the Comet.

Ultimately de Havilland made 114 Comets, of which 74 were Comet 4s, while Boeing went on to sell over 1,000 707s and derivative models. de Havilland began work on a larger, longer-range Comet variant called the Comet 5, but nothing came of it, and in 1960 the company was bought by Hawker Siddeley. de Havilland's final airliner design entered service in 1964 as the Hawker Siddeley Trident, coincidentally just a few months after the delivery of the final Comet 4C. The Trident is covered later in this series, but in brief it was a potentially excellent design that was hobbled during development by an unusually short-sighted design brief. It has the unique distinction of being the only four-engined trijet.

The Comet had a curious twilight. The airlines that bought Comets in the 1950s and 1960s operated them for only a few years, replacing them with Boeing 737s and Douglas DC-9s. In the mid-1960s the British budget airline Dan-Air decided to build up a fleet of jets, and from 1966 onwards Dan-Air essentially bought up every Comet 4 that entered the second-hand market, ending up with a fleet of 49, making it by far the largest operator. Dan-Air specialised in continental package tours, and I like to imagine that if the Comet had a soul, it would have been faintly repulsed at having to shuttle holidaymakers to Spain rather than transporting captains of industry to Johannesburg and Hong Kong.

Dan-Air's operation was fascinating. The airline purchased Comet 4s almost sight unseen, on the assumption that if the airframes were unsuitable for passenger service they might be useful for spares. By removing some of the toilets and reinforcing the floor the company managed to fit 3-2 seating, with a total passenger load of 119. This compared well with an early Douglas DC-9 or Boeing 737, but the Comet was still uneconomical on account of having four engines. However the purchase price of the aircraft was so cheap that Dan-Air still made a profit, and by swapping engines between aircraft Dan-Air managed to avoid the high cost of mid-life servicing. The company continued to use the airliner until 1980, at which point it was the last commercial operator.

But the Comet still had life in it. During development de Havilland had proposed a version of the airliner that would drop nuclear bombs. It had the wings of the Comet but a different fuselage, with a bomb bay and a fighter-style cockpit. The British government had plenty of bombers in the pipeline so the design went nowhere, but in the 1960s the RAF sought a new maritime patrol aircraft. Hawker-Siddeley proposed a militarised Comet, which was selected because the alternatives were either too big, or too small, or too foreign.

The Hawker-Siddeley Nimrod, as it was called, was powered by Rolls-Royce Speys and modified with a large munitions bay and a nose fairing that gave the aircraft a square-jawed appearance. Beyond the first two prototypes the Nimrods were new-build aircraft.

The Nimrod had a bomb bay that could drop homing torpedos and nuclear depth charges. For the Falklands War it was cleared to carry AIM-9 Sidewinder missiles in hardpoints under the wings. There is another world, another universe, in which the Nimrod ended its life hunting down Soviet TU-95s off the irradiated, burning coast of Norfolk, but in our world the Nimrod and its derivatives ended its service life in the 2010s, remaining in service long enough to participate in the downfall of Colonel Gaddafi. During its life it was used for maritime patrol, signals intelligence, and eventually communications and battlefield surveillance.

The Nimrod was not without controversy. In the 1970s and early 1980s the British government squandered over £1bn on a airborne-radar version of the Nimrod, the AEW3, which was cancelled in 1986 with nothing to show for it. An attempt to replace the original Nimrod with an upgraded, modernised successor - the MRA4 - was supposed to enter service in 2003, but development dragged, and eventually the project was cancelled in 2010, after the government had spent £3.4bn on the project. In both cases the key problems seem to have been that the Comet was too small, and that the airframes had been built in the days before robotic manufacture, which forced British Aerospace and latterly BAE Systems to hand-fit modifications to individual aircraft.

Beyond the wasted money the decision to continually upgrade elderly aircraft eventually cost lives. In 2006 a Nimrod caught fire and exploded in the skies over Afghanistan, killing all fourteen on board. Over the years the Nimrods had undergone several rounds of poorly-documented, ad-hoc modifications, and the problem was traced to an internal leak during mid-air refuelling that saturated some insulation with fuel, which then ignited after contact with a hot air pipe. A similar but fortunately non-fatal incident a year later led to the cessation of mid-air refuelling, after which the Nimrod left service in 2010, being replaced by off-the-shelf designs from Boeing.

And that was the end of the Comet. One example remains in taxi-able condition. There are several in museums. There are no flying examples.

Sud Aviation (France)

Sud Aviation was a nationalised aviation business that was formed by a merger of several smaller companies in 1937. Technically it was called SNCASE until 1957 - the French government has always loved acronyms - but I'm going to call it Sud because that's easier to type. You have to pronounce "aviation" in a special way. Aye-vee-ASS-YON. Like that. You have to go real aggressive at the end there. Now you are French.

France's civil aviation industry still functioned during the Second World War. The nation was in theory at peace. But production was mostly diverted to support the German war effort, and the majority of French airliners and flying boats of the 1940s ended up as unsuccessful prototypes. One exception was the forty-seat Sud-Ouest Bretagne. The Bretagne was powered by a pair of conventional piston engines, but later models had a pair of Turbomeca boost jets as well, which improved takeoff performance in hot or high-altitude conditions. One Bretagne was even equipped with Rolls Royce Nene engines as a one-off testbed, although it didn't enter series production.

In 1951 the French government issued a specification for a new airliner that would hopefully bring France into the jet age. Britain and France had slightly different post-war visions of what an airliner should do, although they both realised that the United States would crush them if they didn't move fast. Britain wanted airliners that could service the remains of the British Empire in Africa, Asia, and the Far East, and also cross the Atlantic to reach New York, so Britain's post-war jetliners tended to be moderate-to-large designs with long range. The original, short-range Comet 1 was an exception, but it was thought of as an interim measure while de Havilland stretched and re-engined the design.

In contrast France wanted airliners that could cross France, and continental Europe, and off to North Africa, but not necessarily much farther, so post-war French airliners tended to be small-to-medium designs that prioritised passenger load over range. The specification that led to the Sud Caravelle asked for an aircraft that resembled the Comet, but with a slightly shorter range of around 1,200 miles, and a slightly larger passenger load of around 50 people.

Sud responded with a proposal for a delta-winged jet aircraft, which mutated into a twinjet with wing-mounted engines, then into a trijet with engines in the rear, then finally a rear-engined twin-jet. In the process the aircraft grew until it had a theoretical maximum passenger load of 80, although in practice the actual amount tended to hover around 64.

The Caravelle's configuration, with two rear-mounted engines and a quasi T-tail, was unusual at the time, but it turned out to be very influential. The Douglas DC-9 and BAC 1-11 owed a lot to it, as did the Boeing 727, in fact it essentially became the standard layout for short-range jetliners for the next twenty years. Mounting the engines in the tail kept them away from the passenger cabin and runway debris, at the cost of having to reinforce the wings to cope with upward bending forces in flight. To save time and money Sud licensed the Comet's nose from de Havilland, although internally the Caravelle had three crewmembers versus the Comet's four, dispensing with the navigator / radio operator. Some operators even flew the Caravelle with just two flight crew, years before that configuration became standard.

The Caravelle's prototype first flew in 1955. For the next four years Sud flew the Caravelle on a trials basis, accumulating hours in a variety of different conditions in case there were any unexpected gremlins. The fatigue issue that downed the Comet was known by the time the Caravelle took flight, but Sud nonetheless subjected their prototype to the same water tank testing as the Comet just in case. Sud also used the flight tests as a way of showing the Caravelle off to foreign buyers, which was in practice very effective.

The Caravelle eventually entered service in 1959, with Air France, but it quickly generated sales to other airlines, including SAS, Alitalia, Finnair, and Sabena. There was a notable sale in 1961 to United Airlines of the United States, who ended up buying twenty Caravelles, making them the first US airline to fly European jets. At the time the Caravelle was unique as the only short-haul jetliner, which made it particularly appealing to United, who used it on first-class flights from New York to Chicago and back. Their version had upgraded engines and enlarged cockpit side windows, which became standard for later Caravelles.

The UA sale was Sud's high water mark in the United States. In 1961 the company signed a deal with Douglas whereby Douglas would market the aircraft in the US and potentially licence-build any sales they achieved. The next year TWA signed a deal to purchase twenty Caravelles, but they quickly backed out, and the Sud-Douglas deal expired. A year later Douglas announced their own short-range, rear-engined airliner, the DC-9, which led to grumbles from Sud that Douglas had just been using the Caravelle to test the waters for its new design.

Nonetheless the Caravelle continued to sell internationally. As with the Comet it racked up a small number of sales to a large number of airlines, but Sud was more willing to tailor the aircraft to an airline's specific need, and so there was a bewildering number of variants. The Caravelle 11R of 1967, for example, had a mixed passenger-cargo load for use by African airlines, while the final model, the Caravelle 12 of 1971, was stretched and re-engined to accommodate 140 passengers over a shorter range than earlier models, making it almost an ancestor of the Dassault Mercure. One of its major customers was even Air Inter, who flew it alongside the Mercure.

Ultimately Sud sold 280 Caravelles, beating the Comet more than two-to-one. But it was still a generation one aircraft, saddled with relatively inefficient engines. By the 1980s it had been displaced by the Douglas DC-9 and Boeing 737, which could carry more people over a greater distance for less money. Air Inter ended service of their Caravelle 12s in 1991. The very last operator was Gabon Express, who continued to fly their two Caravelles until a fatal crash in 2004 led to the closure of the airline.

Sud Aviation itself was absorbed into Aérospatiale in 1970. On paper the Caravelle's successor was the Sud Super-Caravelle, but apart from the name and the basic idea of short-haul travel the Super-Caravelle had nothing to do with the Caravelle itself; the design eventually evolved into Concorde.

The Caravelle has gone on to become something of a forgotten pioneer. Of the first three jetliners - the Comet, the Tupolev Tu-104, and the Caravelle - it was the only unqualified success, which unfortunately means that it has a relatively undramatic story. An early crash in 1963 was blamed on the use of flammable hydraulic fluids, later accidents were the result of engine and landing gear failures, but for the most part the Caravelle was no more accident-prone than any other airliner of the period.

As a short-to-medium-haul jetliner it set no records, and beyond the general configuration its design was conservative, although as with the Boeing 727 it had unusual rear-mounted airstairs. It was however very attractive. The rear-engined configuration is fading into history nowadays, but for a while it was extremely common, and yet most of the rear-mounted airliners had a utilitarian look. The Caravelle, with its elongated fuselage and streamlined nosecone, had an elegance about it.

No, tell a lie. It did set one record. During flight testing Air France took one of their Caravelles to an altitude of 40,000 over Paris and cut the engine power, at which point it managed to glide all the way to Dijon, 150 miles to the south-east. The flight took forty-six minutes and was presumably very quiet. Did I mention that the Caravelle had triangular windows? Sud reasoned that passengers wanted to look out and down, not up, so they made the windows wider at the bottom, which reduced the amount of metal they had to cut from the fuselage.

And that's de Havilland and Sud. In the next article, Embraer! And then Fokker, and that weird German airliner that had the engines over the wings.

Saturday, 1 March 2025

Every Jetliner Ever Made: Convair and Dassault

Let's have a look at Every Jetliner Ever Made. In alphabetical order, but with Airbus and Boeing at the end because it wouldn't be fair otherwise. Today we're going to look at Convair of the United States and Dassault of France, who made fascinating airliners notable for being huge flops, because they misjudged the market in subtly different ways.

Before we begin, a picture of a Convair C-131 at Prudhoe Bay, Alaska, in 1979, which has nothing to do with jetliners but I like it:

CONVAIR (United States)

In 1943 Consolidated Aircraft of New York and Vultee of Los Angeles realised that they loved each other very much. They decided to tie the knot and become The Consolidated Vultee Aircraft Corporation, but Convair sounded snappier so that quickly became the official name.

Consolidated was famous for the Catalina flying boat and the B-24 Liberator bomber, while Vultee made the BT-13, which was the USAAF's standard basic trainer during the Second World War. Vultee made almost ten thousand of them. We're talking big military contracts, big government money, and so when the war was over Convair continued to concentrate on warplanes.

In 1953 the company was purchased by General Dynamics, but it continued to operate as an independent unit. In the years that followed Convair became one of those fingers-in-many-pies organisations, with a product range that included anti-aircraft missiles, the F-102 and F-106 supersonic interceptors, a turboprop flying boat, a space rocket - the Atlas - and the staggeringly expensive B-58 Hustler jet bomber.

A Convair F-106 firing an AIM-2 nuclear-tipped missile.

A few things link Convair's post-war jet projects. They were fast! For a while Convair sold the fastest bomber (the B-58), the fastest jet interceptor (the F-106), and the fastest airliner (the 880). And secondly they were all very expensive, extremely specialised, and beset by developmental delays. The F-106 only came about because its predecessor, the F-102, wasn't as fast as Convair hoped, but the company had spent so much money and came so close to specification that the US government gave them a second chance. This was acceptable for government work, but it was a poor fit for the commercial market.

As mentioned passim the Second World War acted as a big reset button for the European aviation industry. Instead of restarting production of pre-war piston-engined designs, Europe decided to skip ahead to turboprops and turbojets. Meanwhile the United States carried on as before, with Douglas and Lockheed restarting production of piston designs. Initially they were successful - between them, the Douglas DC-6 and Lockheed Super Constellation sold over 1,000 units - but by the mid-1950s the US aviation industry found itself in danger of being leap-frogged. In response Boeing gambled on a jet airliner derived from a military contract, Douglas scrambled to catch up with Boeing, and Convair decided it should have a go as well.

Convair's field of expertise was fast bombers and fast interceptors, so the company decided to make a fast airliner, powered by military-style General Electric turbojets. Convair decided that there was space in the market for a fast, regional-to-intercontinental-range airliner aimed at the luxury end of the market. There were even plans to clad the aircraft in a gold-coloured exterior skin, somewhat akin to American Airlines' unpainted aluminium aircraft, but the cost of ensuring that each panel was the same shade of gold was too much and the plan was abandoned.

In retrospect Convair made the same mistake as BAC and Aérospatiale when they developed Concorde. They believed that jet aircraft would continue to be exclusive, that turboprops would continue to service the budget market for decades to come, and that there was a market for a super-fast executive airliner.

In reality there was a market for executive jets, but the demand was met by small business jets rather than full-sized airliners, because business executives generally don't want to share space with ordinary people. Meanwhile everybody else wanted to get to their destination as cheaply and quickly as possible, preferably cheaply.

Convair's design was the CV-880, which made its first flight in 1959, slightly later than the Boeing 707 and Douglas DC-8. In common with the other first-generation jetliners the CV-880 had four engines, which were derived from the General Electric J79, a fuel-guzzling turbojet also used by the Lockheed F-104 Starfighter. It had a three-two seating aisle arrangement, versus three-three for the 707 and DC-8, with slightly larger seats than either. Passenger capacity was around 110, about two-thirds that of the competition. Fuel consumption was similar, but with two-thirds the passenger capacity the fuel-cost-per-passenger was higher.

In its favour the CV-880 had a higher cruising speed than the competition. Convair hoped that the shorter journey times would attract an exclusive customer base, and their advertisements promised all-first-class seating, but as far as I can tell only the launch customer, Delta of the United States, actually flew all-first-class, and then only briefly.

In practice the speed differential barely had any impact on timetables. The 880 had a cruise speed around 40mph or so faster than the Douglas DC-8 and Boeing 707, 600mph vs 560mph, which made for good copy, but in practice it only saved time on shorter routes, and then only 15-20 minutes. For trans-continental US flights and international flights abroad the 880 had to make a refuelling stop, which nullified whatever speed advantage it had.

Japan Airlines bought nine CV-880s, using them on short-to-medium routes while the company's Douglas DC-8s flew long-range.

Even in the 1960s airlines cared about fuel economy. The 880 burned roughly the same amount of fuel as a 707 or DC-8 to take two-thirds as many passengers two-thirds the distance in fractionally less time. To make things worse the CV-880's introduction coincided with the launch of the Boeing 720, a cheaper, shortened version of the 707 that still carried more passengers than the CV-880. For the most part airlines realised that the future of jet travel was low-cost mass-market transport, which left Convair without a market.

Convair only sold 65 CV-880s, including an 880M variant with more fuel and improved avionics. The company then switched to the 990 Coronado, which was similar, but had more efficient turbofan engines and a more complicated wing design. After promising their launch customer, American Airlines, that they could make the 990 fly at 635mph, Convair encountered a series of aerodynamic problems that necessitated the addition of unsightly aerodynamic fairings to the 990's wings. American Airlines cut their order to twenty airframes at a knock-down price. A few more orders trickled in, but ultimately Convair only made 37 990s, many of which were later upgraded to the longer-range, less-draggy 990A configuration.

A Swissair CV-990 (right), next to a Douglas DC-8, courtesy the collection of the ETH-Bibliothek, Switzerland.

The second-largest buyer was Swissair, who wanted something larger than a turboprop but smaller than the Boeing 707. Before the oil crises of the 1970s the CV-990 actually made some sense in the European market, particularly in centrally-located Switzerland. There was for a while a business-class market that had benefited from the post-war boom. After the first wave of Convair owners disposed of their 880s and 990s the aircraft had brief second lives as charter jets, where the low purchase price offset the high fuel costs.

In 1970 a US charter airline called Modern Air flew a former American Airline CV-990 from Berlin to Paris as a one-off, men-only busenvogel flight, where the stewardesses wore see-through lingerie. Even in 1970 this was controversial, and Modern Air's owners told the company to knock it off, but I'm writing about it in 2025 so in that one narrow sense it was a success.

A 990, with its distinctive wing design. The overwing pods were designed to smooth the flow of high-speed air over the wings. In addition the inboard pods had extra fuel storage.

Most 990s were withdrawn from service in the wake of the early-1970s oil crisis, although the airframes were apparently very robust, and a few saw out the 1970s as cargo aircraft. The 880 generally outlasted it, but only for a few years. In the end Convair lost roughly half a billion dollars on the 880 and 990 project, which was a lot of money in the 1960s, and never again tried to make a jetliner.

The two types had a good safety record despite their hot performance. There were plenty of crashes, but they were almost entirely the result of crew error, poor weather, mid-air collisions, and an unusually high number of training accidents.

One 880 became famous outside the world of aviation. Top late rock singer Elvis Presley bought a surplus 880 in 1975 and had it converted into an executive transport. He named it Lisa Marie, after his daughter. Following his death it was sold on, and then re-purchased by Presley's estate. In 1984 it made its final flight back to Graceland, where it remains as a museum exhibit.

A Dassault Mercure, courtesy Eduard Marmet

DASSAULT (France)

Dassault came into being in 1947, although its roots were the pre-war Société des Avions Marcel Bloch, named after its founder, Marcel Bloch. The company was nationalised by the French government in 1937. After the fall of France in 1940 the company was taken over by the Germans, who eventually sent Marcel Bloch to Buchenwald as punishment for refusing to help them enthusiastically enough.

Meanwhile Bloch's brother, Darius, fought for the French Resistance under a series of code names. In 1947 Marcel, who survived his wartime treatment, revived the aviation business, calling it Dassault, as a play on his brother's codename Chardasso, itself a play on the French for "assault tank". He even renamed himself Marcel Dassault, because Dassault sounds way cooler than Bloch.

Can you think of another man who named two different aviation companies after himself, using two different names? Neither can I. In the mid-1950s Dassault developed the Mirage III, a classic multi-role jet fighter with a distinctive delta-winged design. The Mirage III set up Dassault for life, and the company still exists today as an independent entity. Dassault also designed a series of business jets, which are outside the scope of this article, although the Falcon 900 is notable for being the last trijet in series production.

Dassault also made an airliner, the Mercure. It was a disaster. And yet it wasn't a terrible idea. It was developed in the late 1960s as a short-range, high-capacity twinjet that would compete with the Boeing 737 and Douglas DC-9. The initial plan was to engine it with what would become the Snecma/CFM M56, but development of that powerplant was extremely protracted, so Dassault picked the Pratt and Whitney JT8 instead, essentially the same engine that powered the 737 and DC-9. As a result the Mercure had the same amount of engine power as the competition, but it was heavier, and as a result it burned more fuel.

It also had smaller fuel tanks, because Dassault believed there was a gap in the market for a jet that would carry more passengers than the 737 and DC-9. The Mercure had a capacity of around 160 passengers, versus 120-130 for the competition, but the larger passenger cabin meant that most of the fuel had to be carried in the wings, and there was no room to add extra fuel tanks to the fuselage.

There aren't many public domain photographs of the Dassault Mercure. This is Freddie Mercury (left) of the rock band Queen, plus the rock band Queen (pictured).

The Mercure had an unusually short maximum range of around 1,000 miles, about half that of the contemporary Boeing 737 models, and only then with a reduced passenger load. It was essentially a giant regional jet. The project was announced in 1969, with the French government contributing over half the development costs, but it was an international co-production, with the fuselage made by Fiat of Italy and CASA of Spain, the engines by Pratt and Whitney of the United States, and the avionics by SABCA of Belgium. Had the Mercure been a huge success it would have been interesting to see how Dassault might have co-existed with Airbus, which was then in its formative stages.

On paper the Mercure wasn't awful. Despite being heavier than the 737 and DC-9 it was faster, thanks to some clever aerodynamic engineering. The configuration was state-of-the-art, with a heads-up display, a cockpit optimised for just two crewmembers, and autoland capability. On a visual level it was a tidy design that resembled the Boeing 737 or the later Airbus A-320. The project was apparently brought in on time and on budget, and it was certified for flight in 1974.

Sales were slow at first. Disastrously so, not helped by a major oil crisis. Launch customer Air Inter of France ordered 10 Mercures, which began revenue service in 1974. Air Inter operated the aircraft mostly on internal routes from Paris to the south of France and back, but despite trouble-free service the Mercure was met with a hubbub of apathy from other airlines. Dassault failed to sell any more Mercures throughout the entire rest of the 1970s.

A view of Earth, from the Mercury 3 mission.

But there was a happy ending. In 1983 Air Inter asked for one more Mercure, so Dassault upgraded one of the prototypes to production status, bringing the total number of Mercure sales to eleven. And so Dassault managed to sell Mercures in two separate decades. Admittedly this didn't do anything to help Dassault's bottom line - the company hoped to sell three hundred Mercures, but in the end it only managed to sell eleven - but eleven is bigger than ten, isn't it? There was also a twelfth Mercure, a prototype, but no-one wanted it.

Why did the Mercure fail? The oil crisis didn't help. The existence of the Boeing 737 and Douglas DC-9 was a major issue. By 1974 those aircraft were well-established. The Mercure's position as the first airliner from a new manufacturer was a tough sell. The contemporary, brand-new Airbus A-300 languished for several years before Eastern Air Lines of the United States bought a bunch, but no-one came to the Mercure's rescue. As far as I can tell Dassault didn't market the type in the United States. Given the short range, the company would presumably have had to transport a sample aircraft across the Atlantic by cargo ship.

The key problem was a total lack of flexibility. The Mercure only made a profit if it carried a two-thirds-full passenger load over a distance of around 600 miles, which - again, on paper - wasn't necessarily a disastrous proposition. The problem is that no airline beyond Air Inter was interested in an aircraft that could only do that one, narrow thing.

This man invented time.

Had the Mercure emerged a decade later it might have attracted the attention of the nascent low-cost airline industry - passenger capacity was similar to the 1980s-onwards New Generation 737s - but even then the likes of Ryanair and EasyJet would have been unhappy with an airliner that couldn't fly from Dublin to Rome without a refuelling stop. London-Dublin, or Dublin-Edinburgh, or perhaps London-Paris was within the Mercure's reach, but London-Benidorm was out of the question, so it was useless for the British package holiday market.

The likes of Swissair and Lufthansa, whose home bases are centrally placed within Europe, opted for smaller Embraer regional jets instead. As a final nail in the coffin the introduction of France's TGV high-speed rail network in the 1980s removed whatever raison d'etre the Mercure had within France.

An airline that bought the Mercure would have found itself trapped, unable to expand. Dassault mooted a longer-ranged, more efficient Mercure 200, but the project went nowhere, which in retrospect is one of the big "what-ifs" of the aviation industry, because the conceptually similar Airbus A320 went on to be one of the best-selling airliners of all time.

The Mercure remained in service with Air Inter until 1995, shortly before the company was absorbed into Air France. The irony is that during its twenty years of service it had a fantastic safety record, with no crashes and no deaths. In 1986 one Mercure was battered by a hailstorm, forcing the pilot to lean out of a side window to see the runway, but no-one was seriously hurt. Along with the Vickers VC-10 and Hawker Trident it's an interesting example of a technically clever airliner that was laid low by an inflexible specification.

An actual Dassault Mercure, courtesy Dylan Agbagni.

In the 1980s the Mercure was occasionally cited as an example of the failure of the European aviation industry to compete with the US, and during the early years of the Airbus project it was widely assumed that the A-300 would go the same way, but Airbus survived its early fallow period.

Next, Douglas. Many years ago this series of articles would have been titled "every jetliner ever made, but with Airbus, Boeing, and Douglas at the end, otherwise it wouldn't be fair", because Douglas was a giant. And then it was gone. Except that it still existed. But it wasn't Douglas any more. Or was it?