What happened
On the afternoon of Friday, 16 August 1996, a Fairchild SA 227-AC, registration ZK-OAA, was completing a scheduled passenger flight when it experienced a runway excursion at Gisborne Aerodrome. Immediately following touchdown at approximately 12:50 hours, the aircraft began to swerve toward the right. While the pilot initially managed to stabilize the aircraft, a second, more significant swing to the right occurred once the pilot engaged the reverse thrust. This secondary movement caused the aircraft to depart the runway and enter the adjacent grass area. The incident resulted in minor damage to the aircraft, but there were no injuries reported among the 14 passengers or the two pilots on board.
The investigation
The investigation focused on the sequence of events during the landing roll and the operational environment at the aerodrome. Investigators examined the aircraft's behavior during the transition to reverse thrust and reviewed the available emergency response capabilities at the site. The inquiry also looked into the accuracy of aeronautical information regarding airport services and the oversight of flight data recorder serviceability.
Findings
The investigation highlighted several systemic safety deficiencies regarding airport infrastructure and information accuracy. A primary concern was the continued operation of scheduled passenger services at aerodromes lacking dedicated rescue and fire services. Furthermore, the investigation noted that even where services were present, they were often insufficient for the requirements of scheduled flights.
Additional issues identified included:
- Ambiguity in the New Zealand Aeronautical Information Publication regarding the specific nature of rescue and fire services available at various aerodromes.
- Inaccurate data provided within aeronautical publications concerning airport rescue capabilities.
- Inadequate procedures for verifying that flight data recorders were fully operational.