5. Localizing trouble to the circuit. You will do extensive testing in this step to isolate the trouble to
a specific circuit.
6. Failure analysis. This step is multipart. Here you determine which part is faulty, repair/replace
the part, determine what caused the failure, return the equipment to its proper operating status,
and record the necessary information in a recordkeeping book for other maintenance personnel
in the future. While not a part of this step, the technician should reorder any parts used in repair
of the faulty equipment.
Sometimes you may run into difficulty in finding (or troubleshooting) the problem. Some hints that
may help in your efforts are:
Observe the equipment's operation for any and all faults
Check for any defective components with your eyes and nose
Analyze the cause of the failure for a possible underlying problem
Classes of Overhaul Work
There are five classes of equipment overhaul (A, B, C, D, and E). The class defines the type and
scope of work to be done on each equipment by the overhauling activity. (Do not confuse equipment
overhaul with the term regular overhaul.)
CLASS A OVERHAUL.A class A overhaul includes overhaul, repair, and/or modification; for
example a modification could be an Ordnance Alteration (ORDALT), Special Program Alteration
(SPALT), Ship Alteration (SHIPALT), or a field change that will sustain or improve the performance of a
system or component to meet its most-recent design and technical specifications. The end product should
be like new in appearance and operation.
CLASS B OVERHAUL.A class B overhaul includes overhaul and repair that will restore the
performance of a system or component to its original design and technical specifications. Modifications
or alterations are not done unless specified by the customer.
CLASS C OVERHAUL.A class C overhaul includes only repair work on a system or component
specified by a work request or work required to correct malfunctions specified by the customer.
CLASS D OVERHAUL.A class D overhaul includes work related to the open, inspect and report
type of work request. It is intended to be diagnostic in nature and may require various tests. It is normally
associated with preoverhaul test and inspection (POT& I).
CLASS E OVERHAUL.A class E overhaul includes work required to incorporate all alterations
and/or modifications specified for a system or component.
Alterations and Modifications to Equipment
Alterations and modifications to shipboard systems and equipment may take several forms. Some of
these are Ship Alterations (SHIPALTS), Ordnance Alterations (ORDALTS), Special Program Alterations
(SPALTS), and Air Alterations (AIRALTS). These alterations (with the exception of electronic
equipment field changes) are categorized as follows: