authority. This authority can be your work center
Failure Analysis
supervisor, division chief, division officer, or the
After locating the faulty part, review your
engineer officer. They will use the information that you
troubleshooting procedures before making the repair.
p r o v i d e to help eliminate future problems. The
This step will help you determine exactly why the fault
information you provide can form the basis for changes
had a certain effect on the equipment. It will also help
in design, application, or method of operation. It should
you make certain that the fault you found is actually the
now be apparent to you why a complete and thorough
c a u s e of the malfunction, not the result of the
inspection is extremely important.
malfunction. For example, a faulty transistor may have
TESTING AND TROUBLESHOOTING
caused the loss of a certain function. Upon analysis, you
ELECTRICAL AND ELECTRONIC
may determine that inadequate cooling of the transistor
COMPONENTS
caused it to fail. The real culprit could simply be a dirty
air filter or an improperly installed heat sink. In addition
On gas turbine-powered ships, a large part of the
to replacing the faulty transistor, the cause of the
ship's ability to complete its mission depends on the
overheating also must be corrected.
efficiency of the electronics of the engineering plant. As
the technician responsible for these systems, you are the
INSPECTING EQUIPMENT
focal point in ensuring their reliability. If a system fails,
CASUALTIES AND REPORTING
it is your responsibility to repair the system in an
DAMAGE
accurate and timely manner. Whether troubleshooting
or doing PMS, you must test and repair various types of
When casualties or damage occur to electrical or
electrical and electronic components. The information
electronic equipment, you must thoroughly inspect the
in this section is presented so you can become more
equipment and make the proper reports. Damaged or
a w a r e of the various electrical and electronic
deranged equipment or circuits present possible safety
components commonly found in gas turbine
hazards to personnel inspecting the casualties. When
engineering systems.
inspecting or working on damaged electrical equipment,
obey all electrical precautions. During the inspection,
A basic principle you should observe is to
follow all precautions for maintenance on energized
troubleshoot an equipment failure to the component
c i r c u i t s until it is verified that the circuits are
level. Usually, GSEs are expected to troubleshoot and
deenergized.
identify a faulty module or printed wiring board (PWB).
In some cases, the GSE must troubleshoot and identify
INSPECTING EQUIPMENT
faulty components. A quick glance at the Navy's concept
of operation explains why you must troubleshoot to the
Your inspection of damaged equipment should not
faulty component level.
b e limited to a visual examination. A thorough
A deployed ship is a self-sustaining unit. Storage
inspection includes your touching and shaking the
space for bulky items or electronic modules to be used
e l e c t r i c a l connections and mechanical parts. Pay
as ready spares is limited. Therefore, it is logical that the
particular attention to the following points:
ship must store only individual components that are
1. Make certain all electrical connections and
common to several pieces of equipment. Some of these
mechanical fastenings are tight. Overtightening can be
components are discussed in the following sections.
as detrimental as undertightening.
RELAYS
2. See that mechanical parts are free to function.
3. Check the condition of control wiring. Check the
Relays are electrically operated control switches.
wiring for frayed or broken leads.
They are classified according to their use as control
relays or power relays. Control relays are usually simply
4. Check the ventilation paths of rheostats and
known as relays. Power relays are called contractors.
resistors for obstructions.
Contractors are mostly found in controllers.
REPORTING DAMAGE
As a GSE, you will deal mostly with control relays.
Control relays are used in the control of low power
After performing a thorough inspection, you must
circuits. The LM2500 gas turbine engine (GTE) fire
r e p o r t the results of your examination to higher
detection system, for example, uses control relays. On
5-4
