SINGAPORE, March 15 (Reuters) - Singapore Airlines (SIA), one of Asia's largest carriers by capacity, said on Friday it will begin flights to Las Vegas via Hong Kong three times a week from August 2. The introduction of the service coincides with an expected upturn in the air travel market, which in recent months had shown encouraging signs of recovery, SIA said in a statement. This brings the total number of direct flights operating weekly from Singapore to the United States to 45, with the other 42 flights serving New York, Los Angeles, San Francisco and Chicago. SIA shares were trading at S$14.20, up 20 cents at 0610 GMT. ©2002 Reuters Limited.