The hovercraft is an ACV (Air Cushion Vehicle). Seriously, that’s the technical term. The inventor of the ACV is a Brit, Sir Christopher Cockerell. He was a boffin, kind of a forefather to the geek. He helped develop radar (radio detection and ranging) in the Second World War. And Cockerell didn’t just dream up a hovercraft out of a vacuum either. Pardon the pun, because there was a subsequent vacuum cleaner built on the principles of the hovercraft, the Hoover Constellation. It didn’t work that well, but has since become a collectible.
However, we’re getting ahead of ourselves. The ACV idea had been hovering around for a while, so Cockerell must have been aware of it, having studied engineering at the world-renowned Cambridge University. There was Dagobert Mller’s flying wing of 1915, with four aircraft engines providing forward thrust and a fifth blowing air beneath the wing. Konstantin Tsiolkovsky, a Russian rocket scientist and considered to be one of the fathers of space flight, had been working on an air cushion as early as 1921 and published a paper on the subject in 1927. And Finnish engineer Toivo Kaario built a kind of prototype called the Surface Soarer (it was actually called the Pintaliitj, but that’s Finnish for Surface Soarer) in 1937. It was Cockerell, though, who discovered the momentum curtain with two tins and a hair dryer.
It happened like this: Sir Chris had a coffee can and a smaller can of cat food (long since emptied of their original contents and lids and bottoms, just the bits the labels went on). He set the cat food can inside the coffee can concentrically and positioned the hair dryer to blow high-speed air down through the arrangement. At the lower end of these cans, imagine a circular wall of air coming from the hair dryer through the gap between the cans. That’s the momentum curtain and it can trap high-pressure air within it, which can provide lift. Because that lift is created by pressure as opposed to airflow (as used by a helicopter), Cockerell worked out that less power would be needed to create the desired effect.
This was taking place in 1953 and funding was far from forthcoming. Cockerell even had to sell some of his personal possessions to keep the research going. In 1955, he built a working model out of balsa wood and took out a patent soon after. He settled on one front-mounted engine to blow air under the craft and also provide directional thrust. The next step was to try and get the military interested. He did the equivalent of riding a prototype along the corridors of the Pentagon to demonstrate the potential of his creation and the government decided to file the hovercraft under Classified Information. Even then, no one stepped up. Without the aid of joke writer, Cockerell put it perfectly: The Navy said it was a plane, not a boat. The Air Force said it was a boat, not a plane. And the Army were plain not interested.
The hovercraft stopped being a secret after that. As we all now know, the hovercraft did take offwith the help of an American. Norman McCreary of Little Rock, Arkansas, invented the rubber Double-Walled Flexible Skirt that allowed the craft to easily travel over rough surfaces or choppy water. Commercial applications first went across the English Channel, taking much less time than conventional ferries, eventually able to transport 400 passengers, 55 cars and five buses. Although the Channel Tunnel has resulted in no more services on that seaway, the hovercraft is still being used around the world, most notably in search and rescue operations in Finland and around the Great Lakes of North America. The U.S. Army used hovercrafts in the Vietnam War on the Mekong Delta and the Royal Marines deployed one in Iraq. And naturally, people race them. Britain hosted the World Hovercraft Championships in August 2010. Hovercrafts have kind of come and gone, but the time seems right for them to make a return to active duty. With lightweight alloys, carbon fiber, Kevlar and forced induction making huge strides in the car world to improve efficiency, there’s no reason why the same technologies can’t bring the hovercraft swooping into the 21st century.