Commercial aviation utilizes a dual-pilot system primarily for safety, redundancy, and workload management. Having two pilots—a Captain and a First Officer—ensures that if one pilot becomes incapacitated due to a medical emergency or fatigue, the other can safely take control and land the aircraft. This "human redundancy" is a critical layer in the "Swiss Cheese" model of accident prevention. During complex phases of flight such as takeoff and landing, the workload is intense; one pilot focuses on physically flying the plane (Pilot Flying) while the other handles radio communications, monitors instruments, and manages navigation (Pilot Monitoring). This cross-checking system allows for "Crew Resource Management" (CRM), where two experts catch each other's potential errors before they escalate. Furthermore, on long-haul international flights, the presence of multiple pilots allows for mandatory rest periods, ensuring that those at the controls are always alert. FAA and international regulations mandate this dual-crew setup for all large commercial passenger operations to maintain the highest global safety standards.