 While airport officials only commented that the radio navigation system was working normally and declined to comment further on the issue, Thai officials confirmed that a part of the navigation system, called as the Instrument landing system (ILS), had to be taken off due to an expansion program at the airport.The system was planned to be put back on to the runway, however the subsequent 1997 Asian financial crisis caused it to be postponed.A Thai air force pilot stated that due to the removal of the Instrument landing system (ILS), pilots had to use a radio navigation system which was less accurate.