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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.

  • A lot of people ask how I put together these videos. So I'd like to share with

  • you some insights and to plug our sponsor SkillShare. SkillShare is an

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Why You Wouldn't Want to Fly The First Jet Airliner: De Havilland Comet Story

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    joey joey に公開 2021 年 06 月 01 日
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