Equipment-level testing generally concerns power
levels, frequencies, servos, special features, and output
functions. The equipment PMS may require special
external stimulating equipment and special- or
general-purpose test equipment for test measurements.
These test measurements are often time-consuming and
difficult to complete, but are always checked by the
SERT in their effort to ensure optimum readiness.
The goal of fault isolation is to determine
systematically the part or condition responsible for a
fault or degraded operation during testing or tactical
operation. The process often involves impact
evaluation. Impact evaluation requires considering
whether to (1) ignore the problem for the time being; (2)
switch to alternate equipment; or (3) perform corrective
maintenance right away. Impact evaluation information
is provided in the CSTOM.
The CSTOM provides fault isolation procedures
both for faults that were detected during operations and
for faults that were known before the operations. After
a fault has been isolated to a specific unit or interface,
corrective action in the form of repair, replacement, or
alignment must be taken. In the integrated maintenance
concept, alignment is considered as corrective
maintenance only and, like other corrective action,
should be performed only when a fault is indicated.
Fault isolation leads to corrective maintenance. The
corrective maintenance performed may or may not bring
the system back to an operable condition. There may
have been more than one fault contributing to the
out-of-tolerance condition that started the fault isolation
process. The possibility of faulty replacement parts and
incorrect adjustment or alignment also exists.
Corrective maintenance may not have solved the
problem, and may even have added to it. Therefore, each
corrective action must be followed by verification.
Verification normally is done by re-creating the test
environment and rechallenging the function. Where
alignments are concerned, the verification process is
complicated by a requirement that the effect of the
maintenance upon other elements of the combat system
Combat System Technical Operations Manual
(CSTOM) for FFG-7 Class Ships with Lamps Mk
III, S9FFG-BC-CSM-(010, 020, 040)/FFG-7,
Naval Ship Weapon Systems Engineering Station,
Port Hueneme, Calif., 1983.
COMNAVSURFLANT Combat Systems Officers
Manual Instruction 9093.3, Naval Surface Force,
U.S. Atlantic Fleet, Norfolk, Va. 1986.
COMNAVSURFPAC Maintenance Manual, Instruction
4700. 1A, Naval Surface Force, U.S. Pacific Fleet,
San Diego, Calif. 1986.