Third officer is a rarely used civil aviation rank. It was primarily used by Pan Am,[1] particularly on its Clippers flying boats during the infancy of extended range airline routes. The third officer would serve as a relief pilot and aircrew member, and could move between pilot, co-pilot, radio officer, and flight engineer positions to provide a rest period for the primary crews.
The position of third officer is rare in modern civil aviation. Modern airliners only require two pilots, the captain and the first officer.[2] Where relief crew are required for long haul flights, additional captains and first officers will be carried. Junior first officers undergoing training are sometimes known as second officers.