What happened
During a landing at Gold Coast Airport, the left engine thrust reverser of VH-VQG, an Airbus A320, failed to deploy. The malfunction was caused by the presence of a lockout pin that had been left in place following maintenance performed in Adelaide.
The investigation
Investigators examined the maintenance activities conducted in Adelaide prior to the flight. The work was performed overnight on the tarmac under artificial lighting. During the shift, the airport's tarmac lights automatically dimmed at midnight, significantly reducing visibility. Furthermore, rain was falling during the visual inspection of the engine before the cowling was closed.
Because the lockout pin was positioned at the top of the engine, its one-meter red warning flag was not easily visible. The flag lacked reflective material, and the dim lighting made the red colour difficult to discern. Additionally, the maintenance stand, which could have served as a visual reminder of the pin's presence, had already been removed from the area.
Findings
Several procedural failures contributed to the error. The lockout pin was not recorded in the technical log, and it was not booked out of the tool store's computer system. Because the pin was not tracked, there was no mechanism to verify its return to storage.
Furthermore, the crew did not utilize the required cockpit warnings associated with thrust reverser deactivation. This failure to perform specific checks meant that the unremoved lockout pin went undetected during the pre-flight phase and before the aircraft was returned to service.