Flight Lieutenant Apinan Sumanaseni, THAI president, said on Monday that the recent poor visibility at Suvarnabhumi Airport had compelled a number of flights to divert to Don Mueang, Chiang Mai and U-tapao airports. The diversions had affected flight schedules and caused delays, with each diversion costing the airline an extra Bt200,000-400,000 in fuel. Revealing that THAI's maintenance department had recently changed its spareparts maintenance system to accommodate new aircraft, Flt-Lt. Apinan said the change was another cause of flight delays because work on some of the aircraft sent for maintenance was not finished on schedule. When aircraft maintenance was not finished on time, there was a shortage of aircraft, he said, but promised services would be back to normal on January 15.