What Happened To Giant Hovercraft?

This video was made possible thanks to CuriosityStream. Watch thousands of high-quality documentaries and get access to my streaming service, Nebula, using the link in the description. Fifty years ago,

giant

hovercraft

were the pride of Britain. They were a new type of machine that could go almost anywhere, on land, water or any other surface. And they were fast, capable of reaching one hundred thirty kilometers per hour. The largest could carry sixty cars and as many passengers as a jumbo jet. These

giant

s once promised to revolutionize the way we travel. But today they have practically disappeared. To understand

what

made

hovercraft

so revolutionary, consider that they are not like any other vehicle.

In fact, they have more in common with airplanes than with ships. This is because hovercraft are essentially in the air. They work using the principles of lifting and pushing. To take off and hover, fans trap a cushion of air, while propellers generate thrust to move forward. And

what

this all means is that friction and water resistance are significantly reduced, allowing a hovercraft to reach speeds much higher than any boat. But speed is not the only advantage. Because no other vehicle can match the versatility of a hovercraft. At sea, in shallow water, on ice or in a swamp, they can go where no other vehicle can.

Where there is no port, a hovercraft can simply rise out of the water where a ship would run aground. Hovercraft were a brilliant innovation. And in the 1960s, a floating transportation revolution seemed to be on the horizon. When the first hovercraft debuted in the summer of 1959, it shocked the world as it seemed to float almost magically over any surface. Its designer, a brilliant British engineer named Christipher Cockerell, was not the first to come up with the idea of ​​a hovercraft. But modern hovercraft would not be possible without Cockerell's key innovation, called the Momentum Curtain. Early attempts at building hovercraft involved blowing air into an open hull, which didn't work very well and required a lot of power.

Cockerell's innovation was to direct a ring of air toward the outer edges of the helmet, trapping high-pressure air. Which allowed the ship to float much higher off the ground. In 1959, Cockerell and two other pilots flew the first practical hovercraft across the English Channel. But another key innovation would be needed to truly unlock the hovercraft's potential. In 1961, another British engineer proposed equipping the craft with a flexible skirt, which would allow it to float much higher off the ground to better handle uneven surfaces. With the flexible skirt, the hovercraft could become a much more versatile machine. And this caused British aircraft builders to rush to develop their own designs.

Almost overnight, the first small-scale hovercraft transport services began to appear across Britain. In just a few years, hovercraft would go from small prototypes to enormous ships that could carry hundreds of passengers. By the mid-1960s, a hovercraft craze had spread around the world. And countries like the United States and France invested millions in its development. But the British were ahead, and the world's leading company was Saunders-Roe. They had not only built Cockerell's original prototype, but also a series of civilian and military designs. And in 1963, Saunders Roe set out to build a new type of hovercraft. One that would be four times larger than previous designs and built to compete with conventional ferries.

In the English Channel, a ferry took about an hour and a half to cross. A hovercraft would reduce the trip to just half an hour, allowing for twice as many daily crossings. The new giant hovercraft would be designated SR.N4. And it would operate more like an airliner with a crew that would include a captain, a flight engineer and a navigator, plus a deck and cabin crew of eleven. In standard configuration, it would carry 30 cars and 254 passengers, or configured for 609 passengers. No one had ever attempted to build a hovercraft of this size. The economic and engineering risks were enormous.

The world's largest hovercraft debuted in the summer of 1968 with a service connecting Great Britain and France via the English Channel. On board, high-profile guests included Princess Magaret and Christopher Cockerell himself. Passengers marveled at the all-British achievement as the 165-tonne machine gained speed. But what no one realized yet was that the SR.N4's rubber skirt was literally breaking beneath them. Fittings designed to handle the waves were damaged or torn off by rough seas, causing repair crews to scramble to replace them after almost every trip. And just three days after it was put into service, a large wave damaged the ship, putting it out of commission for almost a week.

And it was really just the beginning of the problems. Crossings were periodically canceled due to mechanical problems such as hydraulic and gearbox failures. But an even bigger problem was the weather. The SR.N4 was rated for waves of only eight feet. And in the English Channel it didn't take much to cause those kinds of conditions. In its first three months of service, more than a third of scheduled trips were canceled. The debut had not gone well. And in October 1968, the SR.N4 was completely withdrawn from service to undergo major modifications. Unreliable and apparently unsuitable for open water travel, the future of large passenger hovercraft was in doubt.

Despite the disastrous debut, the cross-Channel hovercraft proved incredibly popular with the traveling public. And when the SR.N4 returned to service, many of the previous problems had been resolved. And the skirt had been redesigned to better resist the waves. By the mid-1970s, there were two aircraft carriers operating iconic hovercraft in the English Channel. And they could barely keep up with demand, as trips were fully booked weeks in advance. But there was still a problem. In reality, neither company was making money. Because the SR.N4 burned a thousand gallons of aviation fuel every hour. And maintenance costs were astronomical compared to conventional diesel ferries.

To offset high operating costs, both companies had to modify their hovercraft to increase passenger and vehicle capacity by widening and lengthening their hulls. In 1978, the largest hovercraft could carry up to 418 passengers and 60 cars. The increase in capacity helped make giant hovercraft more competitive. By the end of the decade, hovercraft were carrying almost a third of cross-Channel passenger traffic. But as the 1980s approached, large civilian hovercraft would face a challenge that no engineer could solve. If the iconic hovercraft were in operation today, they would still be the fastest way to cross the English Channel. Faster than conventional diesel ferries or the high-speed catamarans introduced in 1991.

Faster even than the Channel Tunnel, opened in 1994. But it wouldn't have mattered. The hovercraft as a means of transportation was truly doomed from the beginning. In the early 1960s, they captured the public's imagination with their incredible speed. But that speed came at the cost of almost everything else. Compared to conventional ferries, hovercraft were less reliable, less efficient, less capable in adverse weather conditions, and less comfortable. And it meant that, by the late 1960s, enthusiasm for hovercraft had largely dissipated. And Britain's once-thriving hovercraft industry fell into recession. To make matters worse, fuel prices skyrocketed in the 1970s.

Putting the final nail in the coffin, ensuring that fuel-hungry hovercraft can never be widely adopted as a means of transportation. And it meant that the massive SR.N4s would represent the pinnacle of passenger hovercraft design. But in the 1980s they would face increasingly stiff competition from conventional ferries, which had profit margins wide enough to continually lower fares and win back customers. Giant hovercraft could no longer compete, especially after the opening of the Channel Tunnel in 1994. But no vehicle can match the versatility of a hovercraft. That's why these incredible machines remain relevant today for the world's military, industry and rescue services, even when the iconic SR.N4s were phased out entirely in 2000.

But many argue that floating technology He never reached his full potential. And in the 1960s, Cockerell and British engineers had a much broader vision of a new form of transportation that would float on a cushion of air and reach speeds of three hundred miles per hour. They were called tracked hovercrafts and would have been faster than any train in the world, even to this day. By 1972, engineers had developed the necessary technologies and even built a test track and a prototype train. Apparently they were about to reinvent railroads. But their efforts have been almost completely forgotten. You can learn more about the incredible history of the tracked hovercraft in my latest video available right now on Nebula.

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