Tanker, Kerosene Aircraft
The United States Air Force's aerial refueling aircraft are derivatives of civilian jets. Usually, the aircraft providing the fuel is specially designed for the task, although refueling pods can be fitted to existing aircraft designs if the "probe and drogue" system is to be used. In large-scale operations (and even daily air operations), air-to-air refueling is extensively used; fighters, bombers, and cargo aircraft rely heavily on the lesser-known "tanker" aircraft. This makes these aircraft an essential part of the Air Force's global mobility and the U.S. force projection.
Aerial refueling, also called air refueling, in-flight refueling (IFR), air-to-air refueling (AAR) or tanking, is the process of transferring fuel from one aircraft (the tanker) to another (the receiver) during flight. Applied to helicopters, it is known as HAR for Helicopter Aerial Refueling. The procedure allows the receiving aircraft to remain airborne longer and, more important, to extend its range and therefore those of its weapons or its deployment radius. A series of air refuelings can give range limited only by crew fatigue and engineering factors such as engine oil consumption.
Because the receiver aircraft can be topped up with extra fuel in the air, air refueling can allow a take-off with a greater payload which could be weapons, cargo or personnel: the maximum take-off weight is maintained by carrying less fuel and topping up once airborne. Alternatively, a shorter take-off roll can be achieved because take-off can be at a lighter weight before refueling once airborne.
Bombers have carried armament for defence against enemy aircraft only. They are not intended nor designed to actively engage in combat with other aircraft. The majority have been relatively large and unmaneuverable - although some smaller designs have been used as the basis for specialist fighters such as the night-fighter. Attack aircraft are smaller, faster, and more agile, but when armed for a ground attack mission, less so than a fighter. Attack aircraft may carry air-to-air armament, but typically only infrared-guided weapons (such as the AIM-9) for self-defence.
The KC-10 Extender is an Air Mobility Command advanced tanker and cargo aircraft designed to provide increased global mobility for U.S. armed forces. Although the KC-l0's primary mission is aerial refueling, it can combine the tasks of a tanker and cargo aircraft by refueling fighters and simultaneously carry the fighter support personnel and equipment on overseas deployments. The KC-10 is also capable of transporting litter and ambulatory patients using patient support pallets during aeromedical evacuations. Using either an advanced aerial refueling boom, or a hose and drogue centerline refueling system, the KC-10 can refuel a wide variety of U.S. and allied military aircraft within the same mission. The aircraft is equipped with lighting for night operations.
The KC-135 Stratotanker provides the core aerial refueling capability for the United States Air Force and has excelled in this role for more than 50 years. This unique asset enhances the Air Force's capability to accomplish its primary missions of Global Reach and Global Power. It also provides aerial refueling support to Air Force, Navy and Marine Corps and allied nation aircraft. The KC-135 is also capable of transporting litter and ambulatory patients using patient support pallets during aeromedical evacuations.
Nearly all internal fuel can be pumped through the flying boom, the KC-135's primary fuel transfer method. A special shuttlecock-shaped drogue, attached to and trailing behind the flying boom, may be used to refuel aircraft fitted with probes. Some aircraft have been configured with the Multipoint Refueling System or MPRS. MPRS configured aircraft are capable of refueling two receiver aircraft simultaneously from special "pods" mounted on the wingtips.