Chinese airlines will demand 4,273 large passenger aircraft in the next 20 years, a Chinese airplane manufacturer said here Tuesday. The Commercial Aircraft Corporation of China, Ltd (COMAC) said in its latest forecast report on China\'s aviation market in the next two decades that China is expected to order 4,960 aircraft, including both small and large passenger aircraft worth more than 563 billion U.S. dollars, from 2012 to 2031. In the same period, the global market will demand 31,739 aircraft with a total value of around 3.89 trillion U.S. dollars, according to the COMAC report, which was released at the ongoing China International Aviation & Aerospace Exhibition, being held in Zhuhai of south China\'s Guangdong Province. COMAC expects global air passenger turnover to grow at an annual rate of 4.9 percent in the next two decades, and that of China will expand by 7.2 percent annually.