2015年CRI China Successfully Tests Self-Developed Near Space Craft(在线收听) |
On a cold October day this year in China's Inner Mongolia Autonomous Region, about 100 scientists were busy preparing to test their independently developed high-altitude airship. After a 22 hour flight around 20 kilometers above the earth, the airship successfully landed. The project was jointly developed by Beijing University of Astronautics and Aeronautics and Chinese company Nanjiang Space. Associate Manager of Nanjiang Space Liu Dongxu says the test flight opened a new territory in China's aerospace development. "Near space offers a bridge between aviation and space exploration. Few projects have been conducted in this area. We had little previous experience to draw upon in terms of the environment we are dealing with. It has very specific requirements for the material and the overall performance of the aircraft. " Airplanes can fly within 20 kilometers above the earth, while satellites operate above 100 kilometers from the ground. That leaves the middle section called near space, or stratosphere, which is yet to be utilized by humans. Countries including Japan and the US have been vying to conquer this space in recent years. The Chinese airship is named Yuanmeng, or "to fulfill a dream", referring to the Chinese dream to independently design and produce a near space ship. Liu says the blimp is 75 meters long, has a volume of 18,000 cubic meters and a longest diameter of 24 meters. It can carry up to 300 kilograms in weight. Finding the right material to enable long-duration flight has proven a challenge for scientists. The Chinese airship is filled with helium, so the frame of the ship must be also very light to allow it to float. "The materials of the airship must be able to balance or cancel out the load of the aircraft itself. So we used high strength fiber in building the blimp. Secondly, the material must ensure very low levels of helium leakage. So we designed and produced the material based on these specifications." Solar batteries are used to power the ship, which carries a volume equaling around 10 professional swimming pools. To lighten the weight of the batteries, scientists used membrane-like designs to power the ship. Compared to planes and satellites, airships offer much lower costs. They do not need airports and can be used repeatedly. Most importantly, they can stay over a specific location for extended periods of time, which make them very useful in traffic or environmental monitoring. They also offer great potential in communications, intelligence gathering, electronic suppression and early warning systems. The team behind the airship is already planning to commercially test the technology. Zhu Ming, Associate Professor at the Beijing University of Astronautics and Aeronautics says near space airships could prove very useful in civil missions. "We look at the ships as low-altitude and stationery satellites, and they will be more useful in providing civil services. For example, the blimps can carry communication base stations and provide continued 4G services to coastal or certain other areas. " The team plans to send three more ships to near space in 2016. |
原文地址:http://www.tingroom.com/lesson/cri1416/2015/420172.html |