China?on Saturday completed two more ground slide tests for the Y-20, its biggest home-grown transport aircraft, following its successful January maiden flight, the plane's chief designer said yesterday.

"The successful test flight of the Y-20 marks a milestone in China's aviation industry and we're moving a step closer toward building a strategic air power for the country," said Tang Changhong, chief designer for Y-20, or Transport-20. Following the latest tests at a center in west China, Tang said it took five years for Chinese designers to manufacture and test-fly the jumbo air freighter.

"Compared with heavy-lift transport aircraft developers in foreign countries, our development cycle is pretty fast," said Tang, who once served as the chief designer for the JH-7A fighter-bomber.

Other large strategic air freighters in active service globally include the Antonov An-225, the Ilyushin Il-76 and the Boeing C-17 Globemaster III.

Tang noted the aircraft can be used in rescue relief efforts in earthquakes and other disasters, and will improve the Chinese military's rapid deployment capabilities.

Tang believes the Y-20, whose official codename is Kunpeng, named after a legendary bird in Chinese mythology that can fly thousands of miles, will serve as China's jumbo transport aircraft "over a very long period of time" in the future.

The Ministry of Defense confirmed after the successful test flight on January 26 that the Y-20, mainly developed by the Xi'an Aircraft Industry (Group) Company Ltd, has the highest load-carrying capacity of 66 tons and bears the maximum take-off weight of 200 tons.

"The development and testing of high-end military technology and equipment is in line with China's defense and security policy that is purely defensive in nature," he added.