Air China (0753.HK, 601111.SH) reported profits declined 13% in the first half of the year due to high due costs, Dow Jones reported. Net profits were US$635 million, down from US$730 million a year earlier, though revenues rose by 32% to US$7.06 billion. Fuel costs for China’s flagship carrier were up 53% to US$2.5 billion. Air China’s passenger traffic increased 7.4% year-on-year, less that the average 9.8% increase in domestic air travel. The company cited a “more challenging” business environment, and expects uncertainly to continue into the second half. However, some airlines appear to be weathering higher fuel prices better than others. Competitor China Southern Airlines (ZNH.NYSE, 600029.SH) reported a 33% gain in first-half profits, citing strong demand. China Eastern Airlines (CEA.NYSE, 600115.SH) will release first-half results on Monday, August 29.