RAISING THE WIND.

Dominion, Volume 26, Issue 50, 22 November 1932, Page 2

RAISING THE WIND.

At the Royal Aircraft Establishment at Farnborough an extraordinary tunnel is nearing completion. It is 24ft. in diameter, and it is so arranged that currents of air at speedsi up to 200 miles an hour cun be blown through it. Its purpose is to enable experiments to be made on aeroplanes..' The tunnel is nearly 500 ft. in length, but it is made on a curve and housed in a building 230 ft. long, 140 ft. wide and 90ft. in height. The wind is produced by fans driven by motors of 2000 horse-power. In designing aeroplanes it is) of the utmost importance to know the air resistance of a particular shape of wings, or body or engine cowling. Hitherto experiments have been made cither in actual flight or with _ miniature wipd tunnels. To make them in flight was a risky business. and all dangers will be eliminated by the tunnel The speed of an aeroplane can be enormously reduced by parts whose shapes are not exactly correct. It hns been found that n round stmt has an air resistanoe a hundred times as greatone of stream-line shape.