This post is also available in: heעברית (Hebrew)

China’s largest unmanned solar-powered aircraft has recently set a domestic record by reaching an altitude of more than 20,000 meters during a secretive test flight. The Caihong (Rainbow) was developed by the China Academy of Aerospace Aerodynamics (CAAA), and although developers kept its exact size a secret, it is believed to be about 14 meters long with a 45-meter wingspan, based on earlier prototypes.

Shi Wen, head of unmanned aircraft development at CAAA, said in an exclusive interview with China Daily that the Caihong took off from a northwestern China airport, stayed in the air all day, and landed successfully that night. While the flight reached an important milestone for China’s aerospace industry, the creators told it will take years of work before the aircraft is ready for real use. In the future, they hope, the Caihong will be able to stay in the air for months, or even years at a time at extremely high altitudes.

The implications of such a fuel efficient machine are huge. Shi said that the drone will primarily be used by the government to gather information from around the world, but its services also apply to internet providers, communications companies, and could even help with emergency response time.

The Caihong’s solar-powered status allows it to fly higher and longer than other drones. According to Shi, a normal Chinese fuel-powered drone can only fly at about 8,000 meters, while more advanced drones like the Northrop Grumman RQ-4 Global Hawk from the United States can reach up to 18,000 meters. Solar powered drones are a relatively new project for China’s aerospace developers. Before the Caihong, they created a few smaller prototypes that could only reach a few kilometers in the air.

Shi says that once the Caihong reaches a certain height, it will be free from cloud cover and the sun can power it for as long as its controllers want. While the Caihong is a first for China, it faces competitors from other countries, namely the US Helios Prototype, which was developed by AeroVironment Inc in 2001 and reached the world record height of 29,524 meters.