编辑:
2012-08-09
3.词数:70以上。
Dear editor,
I'm a student of Senior Three. I think my parents should buy me a computer now.
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Situation 1: …
European Shuttle Prototype Lands Safely
导读:欧洲航空防务与空间公司“凤凰号”航天飞机模型在瑞典成功试飞。
Sun, May 09, 2004
STOCKHOLM, Sweden(瑞典首都-斯德哥尔摩) - An unmanned prototype of a European space shuttle glided safely back to Earth on Saturday after being dropped from nearly 8,000 feet up by a helicopter.
Guided by Global Positioning System satellites(全球定位卫星), the German-designed EADS(欧洲航空防务与空间公司) Phoenix was dropped by a heavy-duty helicopter over Sweden at 9:45 a.m. and "landed perfectly" 90 seconds later on a test runway north of Stockholm, a project spokeswoman said.
"Everyone here is ecstatic," said Johanna Bergstroem-Roos, of the North European Aerospace Test Range in Kiruna, 770 miles north of Stockholm.
"This gives us wind in our sails."
The Phoenix shuttle, along with the Ariane 5 rocket, represents the European Space Agency's hope for sending astronauts into space, but project managers concede a full-size version will not be ready until sometime between 2015 and 2020.
The test flight was originally planned for Friday but was postponed so technicians could finish analyzing data from an earlier test of the vehicle's onboard computers this week.
The next step likely will be to drop the prototype from higher altitudes, with the help of a high-altitude balloon, Bergstroem-Roos said. The finished shuttle must be capable of gliding to land from an altitude of 80 miles, she said.
Situation 2: …As motorways become more and more clogged up with traffic, a new generation of flying cars will be needed to ferry people along skyways.
That is the verdict of engineers from the US space agency and aeronautical firms, who envision future commuters travelling by "skycar".
These could look much like the concept skycar shown in the picture, designed by Boeing research and development.
However, such vehicles could be some 25 years from appearing on the market.
Efforts to build flying vehicles in the past have not been very successful.
Such vehicles would not only be expensive and require the skills of a trained pilot to fly, but there are significant engineering challenges involved in developing them.
"When you try to combine them you get the worst of both worlds: a very heavy, slow, expensive vehicle that's hard to use," said Mark Moore, head of the personal air vehicle (PAV) division of the vehicle systems program at Nasa's Langley Research Center in Hampton, US.
But Boeing is also considering how to police the airways - and prevent total pandemonium - if thousands of flying cars enter the skies.
"The neat, gee-whiz part is thinking about what would the vehicle itself look like," said Dick Paul, a vice president with Phantom Works, Boeing's research and development arm.
"But we're trying to think through all the ramifications of what would it take to deploy a fleet of these."
Past proposals to solve this problem have included artificial intelligence systems to prevent collisions between air traffic.
Nasa is working on flying vehicles with the initial goal of transforming small plane travel.
Small planes are generally costly, loud, require months of training and lots of money to operate, making flying to work impractical for most people.
But within five years, Nasa researchers hope to develop technology for a small plane that can fly out of regional airports, costs less than $100,000 (£55,725), is as quiet as a motorcycle and as simple to operate as a car.
Although it would not have any road-driving capabilities, it would bring this form of travel within the grasp of a wider section of people. Technology would automate many of the pilot's functions.
This Small Aircraft Transportation System (Sats) would divert pressure away from the "hub-and-spoke" model of air travel.
Hub-and-spoke refers to the typically US model of passengers being processed through large "hub" airports and then on to secondary flights to "spoke" airports near their final destination. 由于高速公路上的交通堵塞情况越来越严重,一种能够载人穿梭在“空中高速路”上的新一代“飞车”将成为需要。
这就是美国国家航空航天局和一些航空公司的工程师们的意见,他们预测未来人类将会乘坐“飞车”旅行。
这些车可能会和图片中见到的波音公司研发中心设计的概念飞车很相像。
然而,这样的交通工具可能需要25年左右的时间才能投放市场。
人类在过去制造飞车的努力一直都不是很成功。
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