Airline crew members sometimes need to travel to another airport to operate a flight. When they do so without being assigned to work a particular flight, they might occupy a supplementary crew seat, often located in the cockpit or cabin crew area. For example, a pilot might use this type of seating arrangement to position themselves for an upcoming flight assignment.
This practice offers significant operational flexibility, allowing airlines to efficiently manage crew resources and ensure flights are adequately staffed. It also allows crew members to commute to their base or return home after completing a flight sequence. Historically, this system has evolved alongside aviation regulations and the increasing complexity of airline networks, becoming an essential component of modern crew management.