Boeing KC-97 Stratofreighter
Bossier City , LA - Barksdale AFB Museum - Boeing KC-97 Stratofreighter - The USAF began operating the KC-97 in 1950. It purchased a total of 811 KC-97s from Boeing, as opposed to only 74 of the C-97 cargo version. The KC-97 carried aviation gasoline for its own piston engines but it carried jet fuel for its refueling mission, this required an independent system for each type of fuel. However, it was able to offload its aviation gas to a receiver in an emergency in a procedure known as a "SAVE".
These tankers were vitally important to the world-wide Boeing B-47 Stratojet strategic operations. An example was the support of Arctic reconnaissance flights from Thule Air Base.
While it was an effective tanker, the KC-97's slow speed and low operational altitude complicated refueling operations with jet aircraft. B-52s typically lowered their flaps and rear landing gear to slow the aircraft enough to refuel from the KC-97. In addition, a typical B-52 refueling engagement profile would involve a descent that allowed the aircraft pair to maintain a higher airspeed (220-240 knots). In the early 1960s, the Tactical Air Command added General Electric J47 jet pods from retired KB-50 tankers to produce the KC-97L. The jet pods increased performance and made the KC-97 more compatible with jet aircraft.
In 1956, SAC began phasing out the KC-97 in favor of the KC-135. KC-97s continued operating with Tactical Air Command, the Air Force Reserve, and the Air National Guard. The KC-97 was finally retired completely in 1978, when the Texas Air National Guard and Utah Air National Guard exchanged their KC-97Ls for C-130s and KC-135s, respectively. [Wiki}