The person sitting in the right seat of the cockpit, alongside the Captain, is officially called the First Officer (FO) or the Co-Pilot. Both individuals are fully trained and certified pilots, and on commercial flights, they often take turns flying the aircraft to manage fatigue and gain experience. The First Officer is the "second-in-command" (SIC) and is responsible for assisting the Captain (the Pilot-in-Command, or PIC) with navigation, radio communications, and safety checks. In case the Captain becomes incapacitated, the First Officer is legally and operationally prepared to take full command of the flight. On long-haul international flights, there may even be a third pilot—the Relief Pilot or Second Officer—who joins the crew to allow the Captain and First Officer to take mandatory rest breaks in the designated crew bunks during the cruise portion of the journey.