A coffee tin, a cat food can and a hairdryer made the hovercraft
In the early 1950s the British engineer Christopher Cockerell blew air from a hairdryer into the gap between a coffee tin and a cat food can. The fast-moving ring of air acted like a wall, trapping higher-pressure air inside. He called it a momentum curtain, and it became the working principle of the hovercraft.
That curtain meant a craft could float on a cushion of air with far less airflow than earlier ideas required, needing between a quarter and half the power of a helicopter. Cockerell tested models in the Suffolk village of Somerleyton and flew one across Whitehall carpets for officials. The design was classified, but no service wanted it: he joked that the navy considered it a plane, the air force a boat, and the army had no interest. So it was declassified, and in 1958 a government development agency funded a full-size craft from Saunders-Roe.
The SR.N1 first hovered on 11 June 1959 and crossed the English Channel on 25 July. That December the Duke of Edinburgh talked the chief test pilot into letting him drive and went so fast he was asked to ease off. He left a dent in the bow that was never repaired and became known as the Royal Dent.
Early versions rode only 23 centimetres above the surface, so small waves slapped the bow. Cecil Latimer-Needham proposed a double-walled rubber skirt that recreated the air curtain lower down, and a 1.2-metre skirt let the craft climb obstacles nearly that tall. Unlike hydrofoils, a hovercraft can lift off while standing still.
Earlier inventors came close. The shipbuilder John Thornycroft patented an air cushion ship in the 1870s but lacked strong enough engines. An Austrian engineer, Dagobert Müller von Thomamühl, produced a 1915 torpedo boat topping 32 knots that trapped air under its bow, though it never left the water. Hovercraft was originally a Saunders-Roe trademark. Demand later faded, and by 2025 only two year-round public services remained, one crossing between the Isle of Wight and Southsea and the other in Oita, Japan.
Source: Hovercraft
