This giant air-tanker was the key to the large-scale deployment of American troops during Operation Desert Storm. Unlike the KC-135 Stratotankers it supplemented, the versatile and enduring KC-10 allowed thirsty aircraft to refuel multiple times in a single flight, could refuel both USAF and USN aircraft, and carry personnel and cargo even on a refuelling mission. The KC-10A's foremost achievement was that it allowed American aircraft to deploy anywhere in the world directly from their bases in the United States.
In the 1970s, the USAF was on the lookout for a strategic tanker that could allow quick, large deployments overseas by transporting troops and cargo in addition to fuel. McDonnell Douglas (now absorbed by Boeing) was approached, and was asked to modify their established triple-engined DC-10-30CF civilian airliner. The new tanker would need a cargo bay, large fuel tanks, a refuelling probe, and seating area could be added, as well as a probe-and-drogue system if possible. (Although the probe-and-drogue system was not added until much later on.) The resulting aircraft was the KC-10A Extender, and although it looked promising on paper, the USAF undertook testing of the aircraft for half a year before operational models were permitted to enter service.
It proved a delight to fly, if mildly sluggish, comfortable even for aircrew personnel, and most of all, extremely long-legged. A KC-10A Extender could fly, unloaded and fully fueled, 18,000 km without stopping. The original aircraft were painted in white, the only exception being the upper-half of the frontal fuselage, decorated in blue. The KC-10A was intended to support all kinds of aircraft, not with a focus on fighters and bombers like the KC-135, and is more capable when escorting transports, as it can carry the vast amount of fuel they require. After entering service in 1981, KC-10As were largely used to increase the range of Lockheed C-141 Starlifters. KC-10A Extenders were based on the east and west coasts of the United States, as they need to be able to deploy overseas in the shortest period of time possible.
A three-man crew is required to fly Extenders, although this number has varied in the past on shorter ranged missions. The pilot and co-pilot are given command of the aircraft, occasionally relieving each other on long range flights to reduce the risk of fatigue. The flight engineer maintains and looks after the comprehensive electronics, navigation, and avionics systems used in the aircraft. Since transportation is a KC10A's secondary role, the flight engineer acts as the cargomaster, directing the loading of the aircraft. Cargo can be stored on large pallets, a single Extender being able to manage up to 25 of these. As most of the rear fuselage is taken up by the large refuelling boom, a cargo door is located on the port-side of the fuselage to the fore of the wing as opposed to using rear loading ramps. Rollers are used to bring the pallets into the aircraft. The KC-10A can carry a maximum cargo load weighing 76,843 Kg.
The KC-10A is not only capable of refuelling, but has a refuelling receptacle itself to allow it to endure even longer missions. The three distinctive engines are all General Electric CF6-50C2 Turbofans, putting out 233.53Kns of power each. A 4th engine, a Garrett TSPC-700-4, rests in the rear fuselage for emergency situations to act as an auxiliary powerplant.
A boom operator sits on the opposite end of the plane towards the tail, and raises or lowers the flying boom using digital controls. A small window allows the operator to visually confirm the position of friendly aircraft in comparison to the boom during a refuelling, and he uses a radio system to communicate with the pilots to make adjustments if needed. Behind the boom sat a probe-and-drogue system, allowing all types of aircraft to be refuelled. The final production KC-10A did incorporate a probe-and-drogue pod under each wing, allowing it to refuel one USAF aircraft and two USN aircraft at once.
Although the KC-10A remains the only American variant in service, the Netherlands fly a very similar aircraft also converted from the DC-10. Designated the KDC-10A, it is also a direct conversion of the McDonnell Douglas DC-10 Airliner. Although in the future the entirety of the KC-10 fleet may be upgraded to extend its service life, the product of the new American KC-X programme will probably replace the KC-10 or supplement it. KC-10s exist in relatively small numbers, originally totalling 60 but due to an accident only 59 remain. The Extender is the safety champion of the USAF, with not a single one being destroyed by hostiles or maintenance issues. The only Extender to be lost fell victim to a fire while on the runway. As they supplement the KC-135 force they are mainly used to refuel strategic lifters, such as the aforementioned C-141, C-17 Globemaster III, and Lockheed Martin C-5 Galaxy.
From an impressive service debut in which a small group of thirsty A-7D Corsairs was escorted to Britain, to refuelling C-141s as they journeyed from American bases to Alaska, West Germany, and other far reaching areas. The combat debut of the KC-10 was in Libya in 1986, supporting F-111 Aardvark's as they journeyed to their targets on the ground. Twenty-five percent of all Operation Desert Storm missions were flown by 46 KC-10s, and it remains in service today as the most potent strategic airtanker in the USAF's service.
Written by: Pace51