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Subscribe to Naked Science - http://goo.gl/wpc2Q1 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. Over half a century later another inventor took up the challenge and built the first full sized hovercraft. That man was Sir Christopher Sydney Cockerell. His dedicated belief in the air cushion principle earned him a place in the history books, as the inventor of the hovercraft. When he unveiled the first prototype of his extraordinary machine the press were amazed, the headlines called it the “Flying Saucer”. But they did not possibly believe it could work over water. So the scientists took it out onto the bay for its first ever flight over the sea. Cockerell was a well-respected engineer, he already had many patents to his name. He knew the hovercraft would work because of his early experiments, using an air blower, two tin cans, one inside the other, and a set of scales. Clip from the documentary “Extreme Machines - Hovercraft”. Watch it here - http://youtu.be/1sDMOa5jqHA