The successful maiden flight of the Y-20, China's first domestically developed heavy air freighter, marks a step in the country's goal of building a strategic air power, according to military experts and observers.

"A genuine strategic air power must possess a strong power projection capability, which is highly reliant on large aircraft, namely a strategic air freighter and a strategic bomber," Wang Yanan, deputy editor-in-chief at Aerospace Knowledge magazine and a military analyst, said.

"The long-range power projection capability of the Chinese air force still lags behind. But the Y-20 means we have made strides toward building a strategic air power."

He said the breakthrough in the technology of large military aircraft will substantially accelerate the development of China's aviation industry and boost the drive to modernize the People's Liberation Army.

On Saturday, China conducted a test flight of the Y-20, a large, multi-function air freighter that can perform various long-distance transportation tasks.

"The successful maiden flight of the Y-20 is important in promoting China's economic and national defense buildup, as well as improving its emergency response and humanitarian aid abilities," the Ministry of National Defense said on its website on Saturday, adding that more experiments and test flights will be scheduled.

The official codename of the aircraft is Kunpeng, named after a legendary bird in Chinese mythology that can fly thousands of kilometers.

The jumbo air freighter is believed to have been developed by Xi'an Aircraft Industry, a subsidiary of Aviation Industry Corp of China, the major military aircraft manufacturer.

Large strategic air freighters in active service around the world include the Antonov An-225, the Ilyushin Il-76 and the Boeing C-17 Globemaster III.