Incident Overview
During a descent into Hobart, a lithium-ion power bank stored in an overhead locker failed for unknown reasons, leading to a thermal runaway. The power bank had no reported pre-existing damage or other identified problems prior to the flight. However, it was stored with a cable inserted and its ports uncovered, factors that can increase the risk of a fault. Post-flight inspection, combined with cabin crew reports of sounds consistent with lithium battery fire training, indicated that the fire was characteristic of a thermal runaway. As the temperature of the power bank increased, smoke and then flames emerged.
Firefighting Response
As the aircraft was already on descent when smoke was first observed, cabin crew had limited time to manage the fire. They worked together in less than eight minutes to identify the fire, gather equipment, and fight it until it appeared suppressed. They also communicated with the flight crew and moved passengers to alternative seating. Although they had received emergency procedures training, they had never practiced for a lithium battery fire in a compressed timeframe. By the time the fire was considered controlled, only about 90 seconds remained for the crew to secure the cabin for landing. Handling the power bank to remove it from the backpack and place it in a fire containment bag was not feasible given the time constraints. Instead, the crew left the power bank in the overhead locker, which held water poured on the backpack, but there was no assurance the power bank would remain fully submerged or isolated from other lithium battery devices during landing. While no adverse consequences occurred, the situation posed an increased risk of cabin occupant injury and aircraft damage if the power bank had reignited.
Protective Breathing Equipment Issues
Protective breathing equipment (PBE) was available for cabin crew use, and all crew were trained in its operation. Two cabin crew members attempted to don the PBE but found it ineffective due to fitment and communication or visibility issues. As a result, they had no protection from the smoke, increasing their risk of smoke inhalation. Although these crew members experienced no residual effects from the smoke, the incident highlighted that protective equipment should be efficient to don and wear continuously during emergency management.