2. 职称英语
  3. Walk along the River Warnow, in northern Germany, and you may be lucky enoug

Walk along the River Warnow, in northern Germany, and you may be lucky enoug

游客2024-01-02  20
问题     Walk along the River Warnow, in northern Germany, and you may be lucky enough to spot a SeaFalcon, a sleek, white machine with two propellers, two wings and a distinctly unbirdlike tail. It looks like an aircraft. Which is what it is. Except, it isn’ t. It is a ship—at least in the eyes of the International Marine Organisation, which regulates such things. That matters, because ships are much more lightly regulated than aircraft.
    The SeaFalcon is really a ground-effect vehicle. It flies only over water and only two metres above that water. This means the air beneath its wings is compressed, giving it additional lift. In effect, it is floating on a cushion of air. That makes it far cheaper to run than a plane of equivalent size, while the fact that it is flying means it is far faster—at 80-100 knots—than a ship of any size. Its designer, Dieter Puis, thus hopes it will fill a niche for the rapid transport of people and light goods in parts of the world where land and sea exist in similar proportions.
    The theory of ground-effect vehicles goes back to the 1920s, when Carl Wieselsberger, a German physicist, described how the ground effect works. There was then a period of silence, followed by a false start. In the 1960s the Soviet armed forces thought that ground-effect vehicles would be ideal for shifting heavy kit around places like the Black Sea. Their prototypes did fly, but were never deployed in earnest and their jet engines consumed huge amounts of fuel.
    This did, however, prove that the idea worked. And two German engineers, Mr. Puis and Hanno Fischer(whose version is called Airfish 8), have taken it up and made it work by using modern, composite materials for the airframes, and propellers rather than jets for propulsion. One reason the Soviet design was so thirsty is that the power needed to lift a ground-effect vehicle is far greater than that needed to sustain it in level flight. The Soviet design used heavy jet engines to deliver the power needed for take-off. But the SeaFalcon uses a hydrofoil to lift itself out of the water, and Airfish 8 uses what Mr. Fischer calls a hoverwing—a system of pipes that takes air which has passed through the propeller and blasts it out under the craft during take-off.
    The next stage, of course, is to begin production in earnest—and that seems to be about to happen. Mr. Puis says he has signed a deal with an Indonesian firm for an initial order of ten, while both he and Mr. Fischer are in discussions with Wigetworks, a Singaporean company, with a view to starting production next year. South-East Asia, with its plethora of islands and high rate of economic growth is just the sort of place where ground-effect vehicles should do well.
    All of which sounds optimistic. But a note of caution is needed. For another sort of ground-effect vehicle was also expected to do well and ended up going nowhere. The hovercraft differed from the vehicles designed by Messrs Puis and Fischer in that it relied on creating its own cushion of air, rather than having one provided naturally. That meant it could go on land as well as sea—which was thought at the time(the 1950s)to be a winning combination. Sadly, it was not. Hovercraft have almost disappeared. But then, in the eyes of the regulators, they counted as aircraft.
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答案                         想着是船，实则是飞机
    沿着德国北部的瓦尔诺河边漫步，如果运气够好的话，就能看到一艘白色平滑的“海上猎鹰”，它有两个螺旋桨、两个机翼和一个毫不像鸟尾的尾巴。乍一看，像是一架飞机。但是不管它多么像飞机，本身却不是飞机。其实它是一艘轮船，至少管理这类机器的国际海洋组织是这样认定的。因为管理船舶相对于管理飞机来说容易得多，这一点才是关键。
     “海上猎鹰”实际上是一种地效飞行器。它只能在距水面两米的空中飞行。也就是压缩了机翼下的空气，大量增加了托举力。实际上，它飞行在空气垫上。这样一来，它的消耗比同体积的飞机要少得多。而事实上，当它以80～100节的速度飞行时，比任何行船速度都快。因此，“海上猎鹰”的设计者迪特尔-普尔斯希望能在那些和海洋条件比例相当的陆地上填补对人和轻便物品快速运输的不足。
    地效飞行器的原理可以追溯到20世纪20年代，德国物理学家卡尔-维尔斯贝格描述了地效的原理。起初这一理论无人问津，继而遭到滥用。20世纪60年代，苏联武装部认为在黑海等地，地效飞行器将是运送重型装备的理想选择。最初的地效飞行器确实起飞了，但从来没有认真部署过，而且喷气发动机消耗的燃料多。
    然而，这也证明了这个原理是可行的。德国的两位工程师普尔斯先生和汉诺-菲舍尔(他们的设计被称为“飞鱼8号”)采用了这个原理，以现代复合材料建造机身，靠螺旋桨发动机器，而不用喷气推动。急于改造苏联飞行器的原因之一是让地效飞行器起飞的能量远远要大于支撑它在空中飞行的能量。苏联设计的飞行器靠重型喷气发动机产生的能量来推动飞机飞行。然而“海上猎鹰号”是用一只水翼实现机身浮在水面上，“飞鱼8号”则是靠菲舍尔先生口中的“滑翔翼”系统装置助飞，这种系统装置由若干管道组成，推进器内的空气进入管道，并且起飞时在飞行器下方爆炸。
    当然，下一步便是开始认真投入生产，看起来这一点马上就会付诸实践了。普尔斯先生表示他已经跟一家印度尼西亚公司签订了十只地效飞行器的试订单，他和菲舍尔先生一起和新加坡公司Wigetworks进行了协商，有望下一年便开始生产。东南亚，因其众多岛屿的地势和经济的高速发展正符合使用地效飞行器的要求。
    一切听起来都挺乐观的。但是，还要提醒人们一点：另一种人们预期不错的地效飞行器仍然没有成功。Messes Puls设计的地效飞行器上的气垫船和菲舍尔先生制造的交通工具有所区别：因为前者自己带有气垫，后者是靠自然的空气实现气垫这一效用。这样一来，靠自然的空气就意味着地效飞行器不仅能在岛屿上飞行，还能飞行在海上，20世纪50年代有人想把这两者成功组合，然而令人感到悲哀的是，并没有成功。气垫船几乎全部下架。然而也就是那时，监管人员把地效飞行器当成飞机处理。
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