VOA标准英语2013--Students Aim for Aviation History with Human-Powered Helicopter
时间:2019-01-14 作者:英语课 分类:VOA标准英语2013年(五月)
Students Aim for Aviation History with Human-Powered Helicopter
Within reach
What seemed impossible when William Staruk began his PhD studies at the University of Maryland three years ago, is now within reach. He's part of a 50-member team developing a flyer called the Gamera II.
“It has flown for 60 seconds and on a different flight gone to an altitude of nine feet [2.7 meters]." Staruk said. "We’re hoping now to combine both of those into a single flight, get that little bit of extra altitude we need and keep the helicopter controlled and stable so that we can take home the $250,000 Prize.”
The volunteers are divided into the rotor, cockpit, transmission and stability working groups. Weight is a major concern for all of them. The 36-kilogram craft is shaped like a giant x, with 21-meter long arms that look like railroad trusses.
“Everything on the helicopter that is black is carbon fiber," Staruk said. "The blades you see are largely white. That’s insulation 1 foam 2. It’s a lightweight material that we can use to hold the shape of our blades. Those blades are covered in a skin that is Mylar. It is a clear plastic that forms the surface of the wings. ”
Staruk says unlike a normal helicopter with blades on the top and tail, the 4 rotors on the Gamera II - each with two blades at the tips of each cross-piece - are close to the ground.
“So, by keeping our blades low they actually take less power to run," he said. "As we climb, it gets harder and harder for the pilot. That's what limits our altitude.”
The pilot sits suspended under the center of the X, with his feet clipped into bike-like pedals and his hands on a crank. A lightweight cord runs from the wheels spun 3 by the pedals, through the craft, to the rotors.
“As the pilot pedals, it reels in the string just like reeling in a fish," Staruk said. "When the pilot cranks his hands and feet, the rotors all start spinning at the same speed and that lifts us into the air.”
Test Day
On flight test days, PhD student Elizabeth Weiner stands under the craft, yelling commands to the pilot and support team. Disappointed with Gamera II’s latest performance just a few weeks ago, she’s come to the warehouse 4 where it’s stored to inspect the damage.
“There’s a lot of fatigue 5 that happens on all the parts of the helicopter," Weiner said. "And so one of the things that we’re doing now is post-flight testing, going through and making sure that nothing else is broken. We had some problems with blades. But you never know what else is slowly breaking.”
Colin Gore 6 also stops by for a look. He’s a student in materials science and knew little about helicopters before joining the team. But he is thin, 54.4 kilograms, and strong, which made him the perfect test pilot.
“I'm a pretty slim guy, but ’ve got a lot of muscle compared to the rest of my body," Gore said. "I feel like I've got a high profile but probably, I’ve got the easiest job of all of them, just dump power into it and give them the performance that they deserve.”
Meeting the challenge
Despite recent setbacks, Gore’s motivation is shared by his team members. Staruk and Weiner agree that it has been a great run.
“We’ve had the opportunity to go through an actual design and flight test experience and that’s the sort of thing you never get to do," Staruk said. "It’s a lot of fun going out there and building something and flying it and trying to do the impossible”
“For me," Weiner said, "it’s knowing that we did it and we did it first.”
And they are doing it, after being challenged to enter the competition four years ago by aerospace 7 professor Inderjit Chopra. He’s watched as the students invested time and creativity in the project. He’s proud of what they’ve accomplished 8 and what they are about to do.
“This milestone 9 has not been successfully completed yet," Chopra said. "It will be an enormous joy when they complete it. I hope that it should be in 2013.”
The Gamera II team plans to make another attempt at the Sikorsky Prize within two months.
- Please examine the insulation of the electric wires in my house.请检查一下我屋子里电线的绝缘情况。
- It is always difficult to assure good insulation between the electric leads.要保证两个电触头之间有良好的绝缘总是很困难的。
- The glass of beer was mostly foam.这杯啤酒大部分是泡沫。
- The surface of the water is full of foam.水面都是泡沫。
- His grandmother spun him a yarn at the fire.他奶奶在火炉边给他讲故事。
- Her skilful fingers spun the wool out to a fine thread.她那灵巧的手指把羊毛纺成了细毛线。
- We freighted the goods to the warehouse by truck.我们用卡车把货物运到仓库。
- The manager wants to clear off the old stocks in the warehouse.经理想把仓库里积压的存货处理掉。
- The old lady can't bear the fatigue of a long journey.这位老妇人不能忍受长途旅行的疲劳。
- I have got over my weakness and fatigue.我已从虚弱和疲劳中恢复过来了。
- The fox lay dying in a pool of gore.狐狸倒在血泊中奄奄一息。
- Carruthers had been gored by a rhinoceros.卡拉瑟斯被犀牛顶伤了。
- The world's entire aerospace industry is feeling the chill winds of recession.全世界的航空航天工业都感受到了经济衰退的寒意。
- Edward Murphy was an aerospace engineer for the US Army.爱德华·墨菲是一名美军的航宇工程师。
- Thanks to your help,we accomplished the task ahead of schedule.亏得你们帮忙,我们才提前完成了任务。
- Removal of excess heat is accomplished by means of a radiator.通过散热器完成多余热量的排出。