Everything about Kc-97 Stratotanker totally explained
The
Boeing KC-97 Stratotanker was a
United States strategic
tanker aircraft. For many years, it was the backbone of the
United States Air Force's tanker fleet until replaced by the
KC-135.
Design and development
The KC-97 Stratotanker was an
aerial refueling tanker variant of the
C-97 Stratofreighter, greatly modified with all the necessary tanks, plumbing, and "flying boom." The cavernous upper deck was capable of accommodating oversize cargo accessed through a very large left-side door, or transferrable jet fuel was contained in tanks on the lower deck. Both decks were heated and pressurized for high altitude operations.
Operational history
The USAF began operating the KC-97 in 1950. It purchased a total of 816 KC-97s from
Boeing, as opposed to only 74 of the C-97 cargo version. The KC-97 used
piston engines, fueled by
aviation gasoline, but it carried
jet fuel for its
refueling mission. It therefore used independent systems for both types of fuel.
These tankers were vitally important to the world-wide
B-47 strategic operations. An example is the support of Arctic reconnaissance flights from
Thule Air Base. The struggle to start and operate this complex airplane at temperatures of -40
o F was a triumph. Navigation in the Arctic conditions required great skill.
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,
TAC added J-47 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 TAC, the
Air Force Reserves, and
Air National Guard units. They were finally retired completely in
1978, when the
Texas and
Utah Air National Guards exchanged their KC-97Ls for
C-130s and
KC-135s, respectively.
Variants
KC-97A » Three C-97As were converted into aerial refueling tankers with rear loading door removed and a flight refulling boom added. After the design was proven, they were converted back into the standard C-97A configuration.
;KC-97E » Production aircraft were factory-built as aerial refueling tankers with rear loading doors permanently closed, 60 built
KC-97F » As KC-97Es but with 3800hp R-4360-59B engines and minor changes, 159 built
;KC-97G » Production aircraft were factory-built as dual-role aerial refueling tankers/cargo transportation aircraft. KC-97G models carried underwing fuel tanks. Many models were converted into full transport (for example aeromedical) or rescue roles, 592 built, 135 later had refuelling equipment removed and designated C-97G.
GKC-97G » Five KC-97Gs were used as ground instruction airframes.
;JKC-97G » One aircraft was modified to test the underwing J47 jet engines, and was later designated KC-97L.
KC-97H » One KC-97F was experimentally converted into a hose-and-drogue refueling aircraft.
;KC-97L » 81 KC-97Gs were modified with a pair of J47 turbojet engines on underwing pylons.
Operators
