In preparation for an August 2018 scheduled flight from Perth Airport to Christmas Island, an apron engineer fitted landing gear ground locks (LGGL) to an Airbus A320 before it was towed to its departure bay. The apron engineer then went to supervise the refuelling of another aircraft, with the intention of returning for the refuelling of the A320 and removing the LGGL.
Approximately 40 minutes later, a flight crew member’s pre-flight walk-around identified the presence of the LGGL. The captain acknowledged the flight crew member’s observation but anticipated that normal departure procedures would lead to the removal of the LGGL before flight.