descent. Spencer recovered 980 into
Taegu, South Korea, where the base
commander had already received a call
concerning his special visitor and was
ready to receive the SR-71 and its crew.
The electromagnetic reconnaissance
system (EMR) ‘take’ turned out to
be monumental. In all, 980’s ELINT
sensors had ‘sni ed out’ emissions
from 290 di erent radar. Of even
greater signi cance to Western
intelligence analysts were all the
SA-5 signal characteristics that they’d
successfully captured.Middle East action
Among the SR-71’s longest-duration
missions were those own during the
Arab-Israeli Yom Kippur War. A co-
ordinated attack was launched against
the Jewish state on October 6, 1973,
by Syria to the north and Egypt to the
west. The assault caught both the Israelis
and Western intelligence agencies
completely o -guard. Soviet Kosmos
satellites kept the USSR’s Arab allies
appraised of the Israeli military position,
but US satellites were in the wrong place
to assist Israel.‘HABU’
SENSORS
The SR-71A carried a sideways-looking
airborne radar (SLAR) or high-resolution
radar (HRR) in its interchangeable
nose section. Built by Goodyear
Aerospace, the so-called PIP (product
improvement program) radar, designated
GA-531, received X-band Doppler
phase information via its antenna,
which it stored on a recorder that was
downloaded and analyzed upon landing
— it had a ground resolution of about
10ft. PIP was replaced by the Goodyear
Capability Reconnaissance Radar (CAPRE)
in June 1973, which improved ground
resolution to about 5ft.
Senior Crown’s nal HRR was the Loral
Advanced Synthetic Aperture Radar
System 1 (ASARS-1, pronounced ‘A-sars
one’), which was deployed operationally
in 1983. It is believed to have had a
ground resolution at nadir (a point on
the ground directly below the aircraft) ofless than 12in from a cruising altitude of
80,000ft.
A Fairchild Camera Company F489
downward-looking terrain objective
camera (TROC) provided photo
interpreters (PIs) with ground track
veri cation.
Two Hycon HR-308B technical objective
cameras (TEOCs) using 48in focal-length
lenses imaged onto ne-grain lm (about
8 ISO). These were carried in left and right
underside chine bays and were activated
automatically via the aircraft’s astro-inertial
navigation system (ANS), or manually by
the RSO. They took ‘close-look’ imagery of
targets left and right of the aircraft’s track.
Finally, two Itek Corporation HR-9085
operational objective cameras (OOCs)
were also located in underside chine
bays to gather high-resolution, three-
dimensional panoramic imagery via 13in
focal-length lenses. These cameras were
replaced in 1972 by a nose-mounted
horizon-to-horizon, high-resolution,
panoramic optical bar camera (OBC) —
this initially touted a 24in focal-length
lens but was upgraded to a 30in lens in
November 1973.Essential in the execution of virtually all
SR-71 missions was the role of the KC-135Q
tankers. Here, 964 is taking the fi rst of a
‘split load’ during refueling in the ‘Viking
North’ refueling area off northern Norway.
Paul F. CrickmoreOnce both the J58 engines had completed
trim checks on the runway, wheel chocks
were removed and a green light from the
control tower indicated that the ‘Habu’
was cleared for take-off. Here SR-71 979,
callsign ‘Oil 54’, awaits an early-morning
departure from RAF Mildenhall in October- Paul F. Crickmore
SR-71 serial 964, callsign
‘Minty 23’, during an
operational mission
on October 6, 1981. The
JP-7 fuel is leaking from
innumerable small gaps in
the full ‘wet tanks’.
Paul F. Crickmorehttp://www.combataircraft.net // April 2018 105
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