KC-135R Stratotanker

The main mission of the KC-135 Stratotankers flown by the 434th Air Refueling Wing is to provide mid-air refueling to long-range bomber, fighter and cargo aircraft. 

This unique asset greatly 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 aircraft as well as aircraft of allied nations. The KC-135 is also capable of transporting litter and ambulatory patients using patient support pallets during aeromedical evacuations.

Four turbofan engines, mounted under 35-degree swept wings, power the KC-135 to take-offs at gross weights up to 322,500 pounds. Nearly all internal fuel can be pumped through the tanker's 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. 

One crewmember, known as the boom operator, is stationed in the rear of the plane and controls the boom during in-flight air refueling. A cargo deck above the refueling system can hold a mixed load of passengers and cargo. Depending on fuel storage configuration, the KC-135 can carry up to 83,000 pounds of cargo. 

The KC-135 can fly at near sonic speeds and at altitudes up to 50,000 feet. These characteristics allow aircraft to be refueled without slowing down or descending to altitudes where jet engines burn fuel more rapidly. 

There are four models of the KC-135 Stratotanker--the "A", "E", "R" and "T"models. Of the original KC-135As, more than 410 have been modified with new CFM-56 engines produced by CFM-International. The re-engined tanker, designated either the KC-135R or KC-135T, can offload 50 percent more fuel, is 25 percent more fuel efficient, costs 25 percent less to operate and is 96 percent quieter than the KC-135A. The 434th Air Refueling Wing is equipped with the KC-135 "R" model Stratotanker. The major differences in the various models are the type of engines.

The Boeing Company's model 367-80 was the basic design for the commercial 707 passenger plane as well as the KC-135 Stratotanker. In 1954 the Air Force purchased the first 29 of its future 732-plane fleet. The first aircraft flew in August 1956 and the initial production Stratotanker was delivered to Castle Air Force Base, Calif., in June 1957. The last KC-135 was delivered to the Air Force in 1965.

General Characteristics
Primary Function: Aerial refueling and airlift Prime Contractor: The Boeing Company
Power Plant: KC-135R/T, CFM International CFM-56 turbofan engines
Thrust: 21,634 pounds each engine
Wingspan: 130 feet, 10 inches 
Length: 136 feet, 3 inches Height: 41 feet, 8 inches
Speed: 530 miles per hour at 30,000 feet 
Ceiling: 50,000 feet
Range: 1,500 miles with 150,000 pounds of transfer fuel; ferry mission, up to 11,015 miles
Maximum Takeoff Weight: 322,500 pounds 
Maximum Transfer Fuel Load: 200,000 pounds
Maximum Cargo Capability: 83,000 pounds
Pallet Positions: 6
Crew: Three: pilot, co-pilot and boom operator.
Unit Cost: $39.6 million (FY98 constant dollars) 
Date Deployed: August 1956 

(Current as of JUne 2013)