The McDonnell Douglas KC-10A Extender is an off-the-shelf version of the DC-10-30CF airliner; the KC-10A is configured as a dual-role transport/tanker.

Although the KC-10A retains 88 percent of systems commonality with the DC-10-30, it has additional systems and equipment necessary for its Air Force mission. Additions include military avionics, director lights for receiver aircraft, seven bladder fuel cells in the lower fuselage beneath the cargo/passenger area, interconnected with the aircraft’s own fuel system and creating a total capacity of 108.062 kg of fuel, an aerial refueling boom, an aerial re-fueling hose and drogue system, a 3-seat aerial refueling operator station (ARO) and an aerial refueling receptacle. Several aircraft in the KC-10A fleet have been modified with wing-mounted pods to further enhance aerial refueling capabilities. The hose and drogue WARP (Wing Air Refueling Pod) modification allows for the aerial refueling of two aircraft simultaneously. This is extremely helpful when refueling naval fighter groups - a fighter group can be refueled two at a time, reducing the waiting period of the other aircraft and allowing each aircraft to "save" fuel.

During boom refueling operations, fuel is transferred to the receiver aircraft (the first was a Lockheed C-5 Galaxy) at a maximum rate of 4,180 liters per minute; the hose and drogue refueling maximum rate is 1,786 liters per minute. The KC-10A can be air-refueled by a KC-135 or another KC-10A to increase its delivery range.

The McDonnell Douglas KC-10A Extender has been officially credited with the best safety record of any USAF aircraft. One aircraft (82-0190) was lost in a ramp fire at Barksdale AFB, Louisiana , on 17 September 1987 .