What happened
During a night operation at Adelaide Airport, an aircraft was cleared to taxi through a section of the taxiway that was temporarily closed for maintenance. Although the pilot was aware of the active closures via ATIS and NOTAMs, the controller issued a standard taxi clearance that inadvertently directed the aircraft into the unserviceable zone.
As the aircraft entered the closed area, the pilot failed to notice the red unserviceability lights and the aircraft struck one of the temporary lights. Following the impact, the pilot became aware of the error and waited while the lights were removed. Despite hearing radio transmissions regarding the removal of debris from a broken light, the pilot assessed that no impact had occurred and proceeded with the departure without requesting a formal inspection of the aircraft.
The investigation
The investigation examined the controller's actions, the visibility of the closure markers, and the airport's maintenance protocols. It was found that the controller, while alert, provided a routine clearance that failed to account for the temporary closures. While a custom text box had been created on the controller's display to note the closures, it lacked an automated alerting system to prevent clearances into closed areas.
Regarding the physical markers, the investigation found that the three red lights used to denote the 35m wide closed section were difficult to identify against the background airport lighting. Furthermore, the required physical markers were not positioned at the site. The investigation also noted that the airport's method of working plan did not specify the exact number of lights or markers required, leading to a lack of prominence for the closed area.
Findings
- The controller issued a clearance that directed the aircraft through a temporarily closed movement area.
- The pilot did not challenge the clearance, incorrectly assuming the works had concluded.
- The pilot failed to observe the existing unserviceability lights and the aircraft struck a temporary taxiway light.
- The lighting provided was insufficient to alert the pilot to the closed area, and necessary cone markers were absent.
- The airport's working plan lacked specific requirements for the quantity of markers or lights, contributing to reduced visibility of the closed area.
- The pilot continued the flight without an inspection despite indications that a light had been damaged.