A 30-minute power blackout at Don Mueang Airport on Sunday morning delayed 16 flights for about 25-30 minutes, Airports of Thailand (AoT) president Anirut Thanomkulbutr said. The blackout was caused by heavy rain and a thunderstorm, putting the arrival and departure lounges in the dark. The airport has a power backup system, which is used only for essential parts of the airport. Paranee Watthanothai, director of Don Mueang airport, said the blackout began at 4.30am because of heavy rain and the problem was solved in 30 minutes. The failure of the electricuty supply delayed 16 flights by 20-25 minutes each.