The KC-135 Stratotanker was first deployed in August 1956, and has been in operation since 1957. Though the KC-135 Stratotanker is mostly used to refuel planes in-flight, it can also transport cargo, perform reconnaissance work, or be used as an aerial command center. For medical emergencies, the Stratotanker can transport or evacuate patients. Above the fuselage-mounted fuel tanks, there’s a cargo and passenger deck.
Any airplane that is equipped for in-flight refueling can extend their operating range indefinitely. This makes tankers like the KC-135 Stratotanker invaluable for military operations. Though the Stratotanker is an asset of the U.S. Air Force, it’s sometimes made available to other military branches such as the Marine Corps and Navy as well as to other Allied countries’ aircraft.
Internal fuel from the KC-135 Stratotanker is pumped through the flying boom and exits a shuttlecock-shaped drogue that attaches to refueling aircraft. The Stratotanker’s boom operator controls the boom from the rear of the plane. Coordinating the movements of the Stratotanker and receiver airplane can be tricky, and is especially difficult in bumpy air.
From 1975 to 1988, Boeing replaced the original skin on 746 Stratotankers with a superior aluminum-alloy skin. Additional improvements included replacing the engine strut fittings, a number of parts and many thousands of steel fasteners and aluminum rivets.
Fuel efficiency as well as takeoff and carrying capacity were increased for Air Force Stratotankers with the replacement of the original KC-135A engines with CFM56 engines. Those planes were redesignated as KC-135R. The newer engines were also less noisy with reduced emissions. Engines in Air National Guard and Air Force Reserve Stratotankers were replaced with refurbished JT3D engines that had originally been installed in 707 commercial airliners. Those modified Stratotankers were redesignated KC-135E.
Maximum speed: 530 mph
Range: 1,500 miles
Length: 136′ 3″
Wingspan: 130′ 10″
Height: 41′ 8″
Maximum weight: 322,500 pounds
Maximum Cargo Capability: 83,000 pounds of cargo or 37 passengers
Engine(s): CFM International CFM-56 turbofan engines in the KC-135R/T. Pratt and Whitney TF-33-PW-102 turbofan engines in the KC-135E.
Crew: Three, including the pilot, co-pilot, and boom operator. Some KC-135 missions also require a navigator.
Aeromedical Evacuation Crew: Five, including two flight nurses and three medical technicians.