The aircraft maker's new estimate of 6,020 planes, valued at $870 billion (528.91 billion pounds), is up from the 5,580 it estimated last year and represents a near tripling of China's current fleet. The country, the world's second-biggest aircraft market, is essential to Boeing's long-term global strategy.

"New business models like low-cost carrier, regional carriers are driving demand for more direct flights to more destinations," said Randy Tinseth, vice president of marketing at Boeing Commercial Airplanes, speaking at a media briefing in Beijing.

Boeing expects China to overtake the United States as the world's single-biggest aircraft market in the period through 2032.

Chinese airlines are increasingly training their sights on overseas routes as the domestic market cools amid a slowing economy and government budget austerity. The overseas push is also fueled by rising numbers of outbound leisure travelers, expected to double to 200 million by 2020, according to brokerage CLSA.

Besides intensifying its coverage of neighboring countries, Air China alone has opened three new routes to the United States since July, 2013, including launching a three-time weekly service to Honolulu in January, 2014. The last time it launched new flights to the United States was in the early 1980s.

China Southern Airlines, the largest carrier on China-Australia routes, started flying non-stop to New York last month. Even budget carrier Spring Airlines, which flies mostly domestic and some Asian routes on its Airbus Group A320 jets, has been weighing an option to buy wide-body Airbus A330 planes.

(Reporting by Fang Yan and Matthew Miller in BEIJING; Editing by Kenneth Maxwell)

Stocks treated in this article : AIRBUS GROUP, The Boeing Company