This concept describes a physical connection established between two aircraft while airborne, typically to transfer fuel. One aircraft, usually a tanker, extends a specialized hose and drogue system, which a receiving aircraft then maneuvers to connect with. Successful completion of this process allows for the transfer of large quantities of fuel, extending the range and operational endurance of the receiving aircraft.
The implementation of this method is critical for modern military aviation, allowing combat aircraft to remain on station for extended periods and project power globally. Its development during the Cold War significantly enhanced the strategic capabilities of air forces, enabling long-range bombing missions and sustained air patrols. The ability to replenish fuel mid-flight revolutionized aerial warfare and remains a crucial component of air power.