Name: Why You Wouldn't Want to Fly The First Jet Airliner: De Havilland Comet Story
Uploaded: 2021-06-01T02:21:20.000Z
Duration: 10 min
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

Thanks to SkillShare for making this video possible. SkillShare is an online

community where you can learn almost anything, including many of the skills

used to make this video. The first 300 people to click the link in the

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

Subtitles ListPlay Video

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

fatigue

reveal

description

improve