新概念英語第四冊(含lrc文本)Lesson 29 The hovercraft

[ti:δ?] [ar:] [al:] [by:https://www.lrc.com.cn] [00:02.36]Lesson 29 [00:04.48]The hovercraft [00:11.04]What is a hovercraft riding on when it is in motion? [00:17.59]Many strange new means of transport have been developed in our century, [00:22.16]the strangest of them being perhaps the hovercraft. [00:26.70]In 1953,a former electronics engineer in his fifties,Christopher Cockerell, [00:33.94]who had turned to boat-building on the Norfolk Broads, [00:37.60]suggested an idea on which he had been working for many years [00:42.04]to the British Government and industrial circles. [00:45.64]It was the idea of supporting a craft on a 'pad',or cushion,of lowpressure air, [00:53.77]ringed with a curtain of higher pressure air [00:57.56]Ever since,people have had difficulty in deciding [01:01.11]whether the craft should be ranged among ships,planes,or land vehicles-- [01:07.34]for it is something in between a boat and an aircraft. [01:12.04]As a shipbuilder, [01:13.44]Cockerell was trying to find a solution to the problem of the wave resistance [01:18.47]which wastes a good deal of a surface ship's power and limits its speed. [01:24.35]His answer was to lift the vessel out of the water [01:27.72]by making it ride on a cushion of air,no more than one or two feet thick. [01:34.68]This is done by a great number of ringshaped air jets on the bottom of the craft. [01:41.37]It 'flies',therefore,but it cannot fly higher-- [01:46.13]its action depends on the surface,water or ground,over which it rides. [01:53.42]The first tests on the Solent in 1959 caused a sensation. [01:59.42]The hovercraft travelled first over the water,then mounted the beach, [02:04.09]climbed up the dunes, and sat down on a road [02:08.67]Later it crossed the Channel,riding smoothly over thewaves, [02:13.22]which presented no problem. [02:16.09]Since that time, [02:17.25]various types of hovercraft have appeared and taken up regular service. [02:22.95]The hovercraft is particularly useful in large areas with poor communications [02:28.73]such as Africa or Australia; [02:31.93]it can become a 'flying fruit-bowl', [02:34.82]carrying bananas from the plantations to the ports; [02:38.27]giant hovercraft liners could span the Atlantic; [02:42.57]and the railway of the future may well be the 'hovertrain', [02:47.57]riding on its air cushion over a single rail,which it never touches, [02:52.99]at speeds,up to 300 m.p.h.--the possibilities appear unlimited.

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