ZHUHAI - China's independently developed regional ARJ21-700 jet has begun high-intensity test flights in order to get its airworthiness certificates, according to its producer, the Commercial Aircraft Corporation of China (COMAC).

China's independently developed ARJ21 jet is seen at an air show ground in Zhuhai, South China's Guangdong province, Nov 9, 2010. [Photo/CFP]

Tian Min, chief accountant of the COMAC, said Monday at the China International Aviation and Aerospace Forum in Zhuhai that the China-made jet was preparing for a series of difficult and high-risk trials, including tests of the engine and the avionics system.

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Four aircraft were undergoing test flights while another two were being tested on the ground in order to earn airworthiness certificates from the Federal Aviation Administration (FAA) of the United States and the Civil Aviation Administration of China (CAAC).

Since the first trial flights in November 2008, ARJ21-700 jets have completed more than 900 hours of tests in more than 400 trial flights, including high-temperature and high-humidity tests, Tian said.

Tian said the COMAC planned to deliver the first ARJ21-700 plane to buyers in 2011. The company had received 240 orders from home and abroad.