The hovercraft

YOU knew you were living in the age of the hovercraft when James Bond (Sean Connery), impersonating a jewel smuggler, boarded one to cross the English Channel in Diamonds Are Forever (1971). They even blasted out the thrilling 007 theme as the camera zoomed in on a hovercraft symbol above the Port of Dover entrance as if it was an exotic beast, then cut to the SR-N4 Princess Margaret surfing away from the white cliffs.

- Sir Christopher Cockerell

Time would leave the hovercraft behind, but if its Bond cameo looks a bit clunky today, in its heyday the vessel was a British invention to be proud of and it was considered a genuine thrill to travel on one. It was certainly fast, the regular service by the late 1960s taking passengers and cars across to France in 35 minutes, faster than any conventional boat of similar power. According to Guinness World Records in 1995, the SR-N4 Princess Anne completed the Dover-Calais run in 22 minutes, with an unofficial record for the crossing being a little over 15 minutes.

Although Sir Christopher Cockerell is remembered as the inventor of the hovercraft, scientists and engineers had been exploring ways of making an effective air-cushioned sea craft for years. When a boat moves through water, momentum is slowed by the drag on the hull, so the quest had been to find a design that could reduce the friction. Sir John Isaac Thornycroft (1843–1928) built light torpedo craft at his shipyard in Chiswick from the 1870s and, in 1877, patented a concave-bottomed ship that would be carried along the surface on a cushion of air, using a basic bellows system.

The problem of how to provide a consistent supply of air was not fully mastered, however, until Cockerell (1910–99) set his mind to it. The son of Sir Sydney Cockerell, a distinguished curator of the Fitzwilliam Museum, Cambridge, Cockerell had worked for Marconi on radar systems during the Second World War, but, in 1950, he bought a small boatyard at Somerleyton, Suffolk, where he built and let out cruising boats to holidaymakers exploring the Norfolk Broads.