The V-22 Osprey is a tilt-rotor aircraft that takes off and lands vertically like a helicopter and flies like a plane by tilting its wing-mounted rotors to function as propellers. Combining a helicopter's operational flexibility with the greater speed, range, and efficiency of fixed-wing aircraft, the V-22 can perform such missions as troop/cargo transport, amphibious assault, special operations, and search and rescue operations. Begun in FY1982 by the Army and now funded in part by the Air Force, the V-22 has been primarily a Marine Corps program funded by the Navy Department.