1 - The Black Vault

THE COMBAT TALON WEAPONS SYSTEM
CRuas sciH {CS] f.ons
'^"-^^fiy^
■ ^' -^ 1.7
Le(t Navlgalsr
Figure 18. Cross-Scan Mode (Source: 1st SOW, CTF Student Study Guide, Hurlburt Field,
Fla., 23 June 1991.)
override. During maximum bank angle turns, ra -
dar altimeters were likely to indicate greaterthan-actual
altitudes and command a dive.
The AN/APQ-122 had a sophisticated fail-safe
circuitry that monitored the system’s performance
and warned its operators when dangerous
(safety of flight) or substandard operating conditions
developed. The logic of the fail system was
such that fail signals were displayed in front of
the operator who was most concerned. Thus,
most fail indicators were presented on the pilot’s
indicator. Somewhat fewer fails were indicated
on the left navigator’s indicator and none on the
right navigator’s indicator. The right navigator,
however, could monitor the fail displays of the
KA band, X band, and antenna controls. All fail
monitoring lights were duplicated on the maintenance
panel, which was monitored by the left
navigator (fig. 19).
Throughout Combat Talon’s existence, the TFR
performed well. It provided a capability that enabled
the crew to accomplish its low-level mission
during adverse weather conditions and allowed
the aircraft to fly beneath the lethal range of most
known threats. Two aircraft losses—on e in 1967
and one in 1981—were partially attributed to
either TFR design or to operator error. In both
instances, however, all flight deck crew members
perished in the resultant crash, thus leaving it to
accident investigators to determine the cause.
The 1967 crash occurred in North Vietnam during
the SEA war and was never investigated to
determine its exact cause. The 1981 crash was
over open water and limited aircraft wreckage
was recovered. Investigators suspected that a
malfunction occurred in the radar altimeter override
system. Operators continue to rely on the
TFR for their worldwide low-level mission and
express confidence in the system’s reliability.
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