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Some consider the period just before the jet age to be a golden era for air
travel. But flying aboard a piston powered propeller aircraft, well it
wasn't always glamorous. Flights took a lot longer than they do today and the
relentless noise and vibration from the piston engines; well it was exhausting.
And most aircraft couldn't fly high enough to avoid bad weather, so you'd be
in for a bumpy ride. And you'd better have your air sickness bag ready.
But then, seemingly out of nowhere in 1949, along came a new kind of
aircraft. It was sleek, quiet, and nearly twice as fast as some conventional
airliners. Cruising at 40,000 feet, it could avoid messy weather. This was the
de Havilland comet. It shattered conventional thinking and proved that
jet travel was the future. But the excitement would be short-lived because
within months things started to go seriously wrong. And the leap into the
jet age it wouldn't go as smoothly as hoped.
In the 1940's, the British set out to change civil aviation. In fact they
really had no choice. Because after the Second World War, American manufacturers
had the Civil Aviation market cornered. At one point, ninety percent of the world's
airline passengers were flying aboard these: American built Douglas DC-3's. The
Americans left the Second World War with a lot of experience designing and
building military transport aircraft. After the War, with their industry fully
intact, manufacturers could switch to producing civil aircraft based on their
military transport designs. But Britain on the other hand, had to rebuild. Much of
its focus during the war had been on building heavy bombers. So it now needed
to develop the infrastructure and the expertise to compete in the civil
aviation market. If the British were going to become leaders in aerospace,
they had better come up with something extraordinary. But a jet powered airliner,
that was dismissed by a lot of people. The conventional thinking of the day
amongst manufacturers and airlines was that jet engines produce too little
power relative to their fuel consumption, and they were just too unreliable for
civil aviation. But at the same time piston engines were approaching their
limits. To squeeze out ever more power, they had grown large and complex with
superchargers and dozens of cylinders. This made piston powered propeller
engines increasingly expensive to maintain. And you can only spin a
propeller so fast before its efficiency starts to diminish. As part of a larger
effort to develop Britain's post-war aviation industry, the de Havilland
Aircraft Company was awarded the task of building the world's first jet-powered
airliner. The aircraft, which would later be
named the Comet, was developed in secrecy. In fact, untenable designs were
deliberately used to confuse competitors. So when the comet was revealed just
three years later in the summer of 1949, it stunned the world.
Its sleek lines, swept wings, and for integrated turbojet engines, well they
were straight out of the future. Even today, a lot of this aircraft looks
pretty modern. So you can only imagine the impression it would have left on the
flying public in 1952. The comet sent a powerful signal to the
world about Britain's newfound superiority in aerospace. Orders poured
in, and even in America where airlines were still skeptical of jets, Pan Am
placed orders for a larger lengthened version. The Comet was revolutionary
because it had solved a key barrier to efficient jet travel. While turbojets
consumed enormous amounts of fuel at lower altitudes, where most planes of the
year a flew, the Comet would instead cruise at an unprecedented 40,000 feet. Where the air is thin and there's less drag.
Allowing the Comet to consume much less fuel. But to allow its passengers to breathe at such high altitude, the cabin
needed to be pressurized. And while the Comet wasn't the first airliner to
have a pressurized cabin, no other flew so high. The Comet went into service in
1952 and immediately began breaking travel time records. And in doing so, it
became a point of national pride for the British public. But here's the thing, in
some ways, the comet was a little too ahead of its time. With such a clean
sheet design, there were suddenly so many new variables to work with. There were
numerous problems with its electrical and hydraulic systems. But when two
Comets skidded off the runway in 1952 and 53,
the pilots were blamed. It was suspected that they were still flying the Comet as
if it were a piston powered airliner. Over rotating the aircraft on takeoff. It
was later determined that a design change of the leading edge of the
comet's wing was needed. But public confidence in the comet had not been
shaken. and the British remained enthusiastic about jet-powered air
travel. But then, just two months later, another incident. This time far more
catastrophic. A Comet leaving Calcutta ominously disintegrated while flying
through a severe thunderstorm. And only eight months later, another Comet
exploded shortly after taking off from Rome. After these rapid succession of
incidents, BOAC, the airline with the most Comets in service had no
choice but to ground their fleet. The focus shifted to a suspected turbine
explosion in one of the engines. So the engine housing on the other Comets was
reinforced. But public confidence still remained high and when the Comet
re-entered service. Airlines had no trouble selling seats. Yet just three
months later, another comet disintegrated over the Mediterranean. Now the entire
worldwide fleet of comets had to be grounded as their Certificate of
Airworthiness was revoked, An unprecedentedly large investigation
began. And it would reveal that sudden catastrophic depressurization of the
Comet's cabin was to blame, essentially causing comets to suddenly explode apart
in midair. See, the Comets cycles of pressurization and depressurization were
faster than those of any other aircraft. After many cycles, the fuselage began to
fatigue and cracks started to form. Especially around the Comets square
windows, where hard edged corners concentrated stress forces. The entire
comet fleet was grounded for years while the investigation lumbered forward.
But in the end, none of the grounded planes would ever fly again.
And while de Havilland worked to modify its design, switching to round windows
and increasing fuselage thickness, the rest of the world was catching up.
Aircraft manufacturers from around the world introduced their own jet-powered
offerings. And in 1958, the Boeing 707 entered service and Douglas began
producing the DC-8. That same year the, de Havilland Comet 4 entered service. But it
couldn't compete with the American offerings, which were now larger, faster
and more efficient. Only 76 Comet 4's were ever delivered to Airlines. That
compares to over 500 DC-8's and over a thousand 707's America's stranglehold on
the civil aviation market would only grow tighter in the coming decades.
According to de Havilland's chief test pilot, Boeing and Douglas both privately
admitted that they had learned from the Comets pressurization problems. And if it
were not for the Comet, they could have made the same mistakes. The later, larger
and improved Comets would reliably serve airlines
into the 60's and 70's. The Comet last flew commercial passengers in 1980. But
there's no question that the Comet paved the way. The British had taken a massive
risk and brought the world into the Jet Age.
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