Great British Inventions - The Hovercraft

Subscribe to Naked Science - Every other Wednesday we present a new video, so join us to see the truth laid bare... Boats can’t reach high speeds because of the friction between the hull and the water. In 1877 Sir John Isaac Thornycroft, a brilliant British boat designer suggested that trapping air under a boat might reduce the friction problem. He tested his idea with a scale model of a flat bottomed boat with a recess underneath. Air trapped in the recess lifted the boat almost out of the water increasing its speed. Later he built a much more complex model using a clockwork mechanism connected to bellows, the bellows pumped air underneath the boat, as it passed through the water the air acted as a lubricant reducing the boat’s friction and once again increasing its speed. Sadly for Thornycroft his boat needed better engine technology than existed at the time. The patents were never exploited.