Going Public - GPS Declassified: From Smart Bombs to Smartphones - page 84

the Soviet Union, in the early hours of September 1, 1983, became a milestone
in Cold War superpower relations as well as a catalyst for the spread of gps
technology from military to civilian use.
Despite having triple-redundant inertial navigation systems (ins) on board,
the pilot and copilot of Flight ke007 lacked what millions of motorists using
gps today take for granted—the positional awareness that comes from seeing
a moving icon on a map. The pilots blindly trusted that the automatic pilot was
faithfully executing, with ins guidance, the coordinates they had programmed
into it.
Navigation methods have always relied on measuring a traveler's movement
against a fixed reference point, such as the sun, a star, or the magnetic pole.
ins uses gyroscopes to maintain that fixed reference point within the airplane
itself, calculating latitude, longitude, and altitude electronically and feeding
the information into the automatic pilot. At the time of the shoot down, com-
mercial airplanes had been using ins for about a decade with no known simul-
taneous failure of all three systems. 3 The Flight ke007 incident led to
speculation about how two experienced pilots could fly a civilian jetliner 360
miles of course over Sakhalin Island, home to one of the Soviet Union's most
sensitive military installations. Explanations ranged from equipment malfunc-
tion to pilot error to conspiracy theories that the flight was on a covert spy mis-
sion. Numerous books and articles have examined the flight and these theories
in detail, but it was not until 1993, after the breakup of the Soviet Union and a
decade after the incident, that Russian Federation president Boris Yeltsin turned
over the black boxes to investigators. The cockpit voice recording proved con-
clusively that the pilots were unaware they were off course (undoubtedly the
reason Soviet military officials never acknowledged finding the black boxes
and withheld the evidence). The most plausible explanation is that the pilots
“armed” the ins but it never fully “engaged.” This could have happened,
because early in the flight the airplane was already several miles farther off
course than the maximum distance the autopilot computer was programmed
to accept when transitioning to automatic ins. 4 That left the airplane on a mag-
netic compass heading that carried it farther and farther off course. Having
earlier sailed over Soviet territory above Kamchatka Peninsula and later fail-
ing to respond to radio contact on a frequency they were not monitoring or to
notice bullets fired past the craft in the darkness, the pilots appeared to Soviet
fighters to be executing an evasive maneuver with their routine “step-climb,”
a move that sealed the flight's fate.