The Airport Authority also stated that the VOR had to have been operational at the time, because the pilot was able to make inbound and outbound turns using the VOR as a reference. The localiser also had to have been operational and used by the pilots, because the aircraft had crashed on the extended centerline of the runway. Data collected from the aircraft's flight recorders shows the pilots did not make sure of the airport's DME and VASI lights, and since their altimeters were working correctly, ignored or did not maintain awareness of the aircraft's altitude.