CHARLOTTE, N.C. -- The Star Alliance has had a good month, and United Airlines has been one of the main beneficiaries. In a year when a principal theme for legacy carriers was global expansion -- to China, India, Europe and Africa -- the largest of the air alliances had a December to remember, formally adding two major Chinese airlines and announcing that a big Indian carrier will also join. United CEO Glenn Tilton applauded the arrival of Air China and Shanghai Airlines into the alliance in a taped message to employees last week. "It is difficult to overstate the importance of these two Chinese carriers for United and the continued growth of our services to China," he said. Air China, one of three state-owned carriers in China, is based in Beijing, while Shanghai Airlines competes with state-owned China Eastern in Shanghai. United, a unit of UAL ( UAUA), operates five daily flights between the U.S. and China, serving both Beijing and Shanghai. The welcoming ceremony for the Chinese carriers, held in Beijing, was chaired by Tilton. It "received significant media coverage in China, and has been an opportunity for United to really demonstrate our presence and leadership in Star and in the China market," Mike Whitaker, United senior vice president for alliances, said during the same taped message.