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the description. This is a Rotodyne. And it might look like a helicopter and

an airplane mashed together, but it's neither. It's a lot more revolutionary.

Because when it debuted over 60 years ago, the Rotodyne was going to be a new

form of mass transport. The quickest way to move from one city center to the next.

Landing on downtown rooftops and heliports, but flying much faster, further

and more economically than any helicopter. And airlines were interested.

But then, as the Rotodyne looked set to revolutionize intercity transport, it just disappeared.

To understand why this machine was so revolutionary, consider that it doesn't

work like a helicopter. A helicopter uses engine power to spin a rotor blade, which

forces air down to create lift.Tilting the rotor is what allows the helicopter

to move in a given direction. That's the basic idea. But that's not how Rotodyne

works. On a Rotodyne, the large rotor isn't powered. It isn't even connected to

a motor. Instead, as air passes naturally through the rotor blades, it causes the

rotor to spin around like a pinwheel. And this creates lift. The Rotodyne still has

wings and a pair of turboprops, much like an airplane. But in forward flight, the

un-powered spinning rotor lifts more than half the aircraft's weight. With this

unique design, the Rotodyne flew faster than any helicopter of the era. And it

was far more efficient. And even though the rotor wasn't driven by a motor, the

Rotodyne could still hover and take off and land vertically just like any helicopter.

That's because at the end of each rotor blade were small tip jets. During

takeoff and landing, fuel and compressed air supplied by the turboprops would

ignite to spin up the rotor. Once in forward flight, the tip jets were shut

off and the rotor would once again spin freely. By 1959 the Rotodyne was

attracting worldwide interest. Because for one thing, it promised to

revolutionize the way we traveled between cities. In the 1950's and 60's,

intercity air travel was on the rise. But while a trip from New York to Boston by

airplane might only take about an hour, you'd also need to get to and from the

airport. And in many congested cities, that was beginning to take longer than

the flight itself. One solution was to use helicopters.

In April, the new helicopter service is due to open from the top of the Pan-Am building.

If the service does come about, you'll be taking off from the fourth highest building in New York.

59 storeys up. it's hoped that eventually the service will carry 5,000 passengers a day.

5,000 passengers who would otherwise be condemned to this.

By the 1960's helicopter airlines had cropped up in major American cities.

Letting passengers and skip the traffic by flying right over it. The problem was,

none of them were actually making money. Because helicopters were simply too

inefficient, operating anywhere from 20 to 30 cents per seat mile. And the only

way helicopter Airlines like New York Airways could even exist was through

government subsidies to offset operational costs. But the Rotodyne was

going to change all that, bringing costs down to as little as 4 cents per seat

mile, which would make helicopter airlines profitable. And the Rotodyne

wasn't just a better helicopter. With vastly improved speed and range, it would

be a new way to travel between cities, linking one city center to the next.

The concept behind the Rotodyne dates all the way back to the early 1920's, when

a pioneering Spanish inventor set out to build a safer plane. By adding an

un-powered freely spinning rotor, his planes could fly slowly without stalling,

making them inherently safer than airplanes. In fact, without any forward

motion, the planes would simply glide back to earth, slower than a parachute.

They were called autogyros. Over the years, they were used in military reconnaissance and

even to deliver mail. But by the 1940's, helicopter technology improved and autogyros

largely fell out of favor. But decades later, British aircraft

manufacturer Fairey aviation still saw enormous potential in the autogyro

concept. If the vertical takeoff and landing capability of a helicopter could

be combined with the speed and efficiency of an airplane, Fairey would

have something truly special on their hands. With the help of funding from the

British government, the first Rotodyne prototype took to the skies in 1957.

It could carry 40 passengers 700 kilometers and reach speeds of over 300 kilometers per hour.

All while being able to land and take off on a space not much larger than

the aircraft itself. And after 350 successful test flights, the Rotodyne

proved to be safe and capable. But of course, it all went to [expletive].

For one, the Rotodyne's tip jets made a lot of noise.

And that was going to be a problem right in the middle of a city. From the start,

there were doubts about whether the public would tolerate it. And noise is

often believed to be the reason why the Rotodyne failed. But that's not the whole

story. After proving their prototype, fairy moved on to develop a production

version. A larger more capable Rotodyne that could carry up to 75 passengers. And

it promised to be quieter. Ferry spent years developing noise suppressor

technology for the Rotodyne's tip jets. And while progress was slow, by 1960

the engineering team had reduced noise by over 15%. And airlines were interested,

with small orders coming in from around the world. Not bad for an entirely new

kind of transport. But to get the production version built, Fairey still

needed about £10 million more in funding from the British government. And it was

money they'd never get. Because at the start of the 1960's, Britain's aviation

industry was a mess. Too many aircraft builders were building too few planes

and relying heavily on government sponsored projects. The solution was to

force these companies, including Fairey Aviation to merge. And the Rotodyne got

caught in the shuffle, competing with a number of other helicopter projects.

progress was also slowed by difficulties sourcing more powerful engines. And the

need to reduce tip jet noise even further. When it became clear that the

Rotodyne wouldn't be delivered to Airlines on time, and the eventual cost

of each Rotodyne would have been too high,

one by one orders were cancelled. In 1962, the British government, facing economic

pressures, suddenly pulled funding for Rotodyne. And the half

helicopter, half plane, once promising to revolutionize intercity travel... just

disappeared. The working prototype and technical research were quickly

destroyed. Leaving only a few small pieces for museum display

The Rotodyne failed to change air travel and only a single prototype was ever

built. But not all ambitious leaps forward in engineering lead to such

failure. Take the DC-3. A machine that in its time, revolutionized air travel and

earned a legendary status in wartime. Over 16,000 DC-3 variants were built.

This remarkable plane took the skies just three decades after the Wright

brothers first flight. And yet, hundreds of DC-3's are still flying today. Learn

about this plane's incredible story on CuriosityStream. A streaming service

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makers in the world. From history and nature, to engineering and design. You can

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