原文：http://www.chinacompositesexpo.com/en/news.php?show=detail&c_id=92&news_id=4917According to state-owned newspaper China Daily, the Caihong, or Rainbow, solar-powered drone, developed by the China Academy of Aerospace Aerodynamics (CAAA), set the record during a test flight last week at an unidentified airport in Northwest China.


It flew at an altitude of 20,000 meters long enough for the flight to be classified as a success, Shi Wen, head of unmanned aircraft development at the CAAA, said in an exclusive interview on Thursday.

He said the drone took off in the morning and flew back to the airport late at night. It will take several years for designers and engineers to improve and test the aircraft before it is delivered to users.

The aircraft is able to fly above a large area and features flexibility and good economy. Future improvements will enable it to remain aloft several months or even several years. Potential buyers mainly will be government departments and companies involved in communications, internet, Earth observation, emergency response and marine survey and inspection, according to Shi Wen.

He declined to reveal the size of the drone, but earlier reports said a similar type aircraft developed by his team was 14 m long with a 45 m wingspan, specified China Daily.

In the category of solar-powered drones, Chinese institutes have developed some experimental models, but they are smaller and technologically unsophisticated compared with the Caihong, and their highest operational altitudes are at thousands of meters, Shi Wen said.

He explained the higher a solar-powered drone can fly, the longer it is able to remain in the sky because there are no clouds 20,000 m above the ground and the airflow there is stable. Thus, the drone can fully use its solar cells to generate power. As long as the solar power system works well, the aircraft can stay in the air as long as the controllers wish.

Previously, according to China Daily, the US and United Kingdom developed solar-powered drones capable of flying as high as 20,000 m. The altitude record for a solar-powered drone, 29,524 m, was made by the US Helios Prototype, developed by AeroVironment Inc in California, in August 2001.

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