A model of a Commercial Aircraft Corp. of China?C919 aircraft is displayed as Jin Zhuanglong, the company's chairman, background third right, speaks with guests at the Singapore Airshow in Singapore, on?Feb. 14, 2012. [CFP]

The Commercial Aircraft Corp of China, or COMAC, secured a contract to sell another 20 C919 jets to BOC Aviation, the wholly-owned leasing unit of Bank of China.

The latest order, signed yesterday, boosts the aircraft maker's total orders for the 150-seat Chinese-made aircraft to 235.

"China's civil aviation regulator encourages domestic carriers to buy and use the domestically-developed aircraft to support the development of home-made planes," said Li Jiaxiang, director of the Civil Aviation Administration of China, the regulator.

The signing of the contract with COMAC builds upon the 50 billion yuan Strategic Cooperation Framework Agreement signed between the bank and the aircraft maker in June, said Robert Martin, managing director and CEO of BOC Aviation, an aircraft leasing company which owns 180 planes that are leased to major airlines globally.

Also yesterday, COMAC signed a contract with Germany-based Liebherr Group and Chinese Landing Gear Advanced Manufacturing Corp to jointly develop landing gear for C919.