I
T’S SOBERING TO think that the
Lockheed SR-71 — widely known
as the ‘Blackbird’ by those outside
the program — fought and won
its rst critical battle six months
before the US Air Force received its
rst operational A-model.
The Central Intelligence Agency
(CIA) had very reluctantly become
involved in high-altitude strategic
reconnaissance of the Soviet Union,
following recommendations to President
Eisenhower from a highly in uential
US government think-tank known as
the Land Panel. Comprised of leading
scientists, industrialists and academics,
it believed, to the chagrin of the
USAF’s Strategic Air Command, that a
civilian agency rather than a military
organization should undertake such
sensitive missions. The premise was
that should a military reconnaissance
aircraft be forced down deep within
Soviet territory, it might be construed as
an act of war. This point resonated with
the President, a former US Army four-
star general.
The panel also recommended that
a strange, glider-like jet, designed by
Lockheed’s legendary Skunk Works,
should be built to conduct such missions,
as opposed to two rival designs backed
by the USAF. As a result, the CIA began
ying the Lockheed U-2 on over ight
missions of the USSR in July 1956.
However, radar detection of these ‘covert’
ights led — not surprisingly — to Soviet
objections to this blatant violation of
their sovereign airspace.U-2 successor
In response, Eisenhower temporarily
suspended the U-2 over ight program
and simultaneously challenged Lockheed
and the CIA to make the aircraft invisible
to Soviet radar. In a project codenamed
Rainbow, the Skunk Works boss,
aeronautical design genius Clarence L.
‘Kelly’ Johnson, and his team worked
closely with their CIA customer to develop
U-2 radar ‘camou aging techniques’.
However, these were of limited success
and the decision was made to build a
U-2 replacement — the Lockheed A-12.
Known as the Oxcart program, a contract
for just 12 aircraft (including one twin-seat
pilot trainer) was placed by the CIA on
February 11, 1960.
These exotic, extremely expensive
aircraft would be much more di cult
for Soviet radars to acquire and track,
generating a radar return of just 12square yards (10m^2 ) at early warning
radar frequencies (200-400MHz), and 2.4
square yards (2m^2 ) at air-to-air frequencies
(10GHz). These results, dramatic for the
time, would be achieved by reducing
the aircraft’s radar cross-section (RCS)
by blending its shape and incorporating
radar-absorbing materials (RAM) in its
construction. To further guard against
successful airborne or surface-to-air
missile (SAM) interceptions, the A-12
would y at sustained altitudes and
speeds dramatically greater than those
of the subsonic U-2. During operational
missions, Oxcarts ew up to 86,000ft and
Mach 3.2, compared to the U-2’s 76,000ft
and Mach 0.62.
On February 18, 1963, the USAF
ordered six Lockheed R-12s, on the
understanding that an additional 25
would be ordered by July 1. Later that
year the aircraft was redesignated as the
SR-71. Essentially these aircraft were a
two-seat version of the single-seat A-12,
but whereas Oxcart primarily gathered
photographic intelligence (PHOTINT) the
SR-71 was equipped with an enhanced
array of sensors that could include
panoramic and ‘close-look’ cameras or, if
weather conditions required, a powerful
ground-mapping radar to collect radar
intelligence (RADINT).
Known within the air force as the
Senior Crown program, the SR-71 was
allocated to SAC and operated initially
by two squadrons, the 1st Strategic
Reconnaissance Squadron (SRS) and the
99th SRS (the latter was deactivated as
an SR-71 unit and its assets absorbed by
the 1st SRS on April 1, 1971). Both were
under the auspices of the 9th Strategic
Reconnaissance Wing (SRW), based at
Beale Air Force Base near Sacramento,
California. Although Beale was the SR-71’s
home base, most of its operational
missions were own from two forward
operating locations, or detachments.
Just three months after Lockheed was
awarded the A-12 contract, an event
occurred that had a profound impact on
Oxcart. Despite his misgivings, Eisenhower
continued to sanction a limited number
of U-2 over ights on the basis of necessity
and the ongoing failure of the Corona
satellite reconnaissance program. On May
1, 1960, Soviet radar and SAM technology
nally caught up with the U-2 program
when CIA pilot Francis Gary Powers
was shot down by an SA-2 ‘Guideline’
missile in the vicinity of Sverdlovsk and
taken prisoner. The action vindicated
building a stealthy, high-performanceLEGEND
OF THE
U-2 replacement. However, Eisenhower
assured Soviet premier Khrushchev
that there would be no more manned
over ights for the duration of his
administration, an assurance upheld by
every subsequent US President.Okinawa debut
By the time the A-12 became operational
in June 1965, it had been overtaken
by world events. As the US became
increasingly embroiled in the Vietnam
War, instead of over ying the Soviet
Union three aircraft were deployed to
Kadena AB on the Japanese island of
Okinawa in May 1967. From there they
conducted Operation ‘Black Shield’ —
reconnaissance-gathering missions,
primarily over North Vietnam. As the war
intensi ed, increasing SA-2 SAM defenses,
particularly around the capital Hanoi, had
rendered it a no-go area for USAF U-2s.FEATURE ARTICLE // ‘SKUNK WORKS’ AT 75
100 April 2018 //^ http://www.combataircraft.net
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