MAINTENANCE ALLOCATION CHART (MAC)
or module (component or assembly) in a manner to allow
General. This appendix provides a summary of
the proper functioning of an equipment or system.
the maintenance operations covered in the equipment
literature. It authorizes categories of maintenance for
specific maintenance functions on repairable items and
h. Replace. The act of substituting a serviceable
components and the tools and equipment required to
like part, subassembly, or module (component or
perform each function. This appendix may be used as
assembly) for an unserviceable counterpart.
an aid in planning maintenance operations.
The application of maintenance
services (inspect, test, service, adjust, align, calibrate,
functions will be limited to and defined as follows:
replace) other maintenance actions (welding, grinding,
resurfacing) to restore serviceability to an item by
a. Inspect. To determine the serviceability of an
correcting specific damage, fault, malfunction, or failure
item by comparing its physical, mechanical, and/or
in a part, subassembly, module/component/assembly,
electrical characteristics with established standards
end item or system.
b. Test. To verify serviceability and to detect
incipient failure by measuring the mechanical or
(service/action) necessary to restore an item to a
electrical characteristics of an item and comparing those
characteristics with prescribed standards.
prescribed by maintenance standards (e.g., DMWR) in
appropriate technical publications. Overhaul is normally
the highest degree of maintenance performed by the
c. Service. Operations required periodically to
Army. Overhaul does not normally return an item to like-
keep an item in proper operating condition, i.e., to clean
(decontaminate), to preserve, to drain, to paint, or to
replenish fuel, lubricants, hydraulic fluids, or compressed
k. Rebuild. Consists of those services/actions
necessary for the restoration of unserviceable equipment
to a like-new condition in accordance with original
d. Adjust. Maintain within prescribed limits by
manufacturing standards. Rebuild is the highest degree
bringing into proper or exact position, or by setting the
of materiel maintenance applied to Army equipment.
operating characteristics to the specified parameters.
The rebuild operation includes the act of returning to zero
those age measurements (hours, miles, etc.) considered
e. Aline. To adjust specified variable elements of
in classifying Army equipment/components.
an item to about optimum or desired performance.
Explanation of Format
f. Calibrate. To determine necessary corrections
and cause corrections to be made on, or to adjust
a. Group Number. Column I lists group numbers,
instruments or test measuring and diagnostic equipment
whose purpose is to match components, assemblies,
used in precision measurement. Consists of the
subassemblies, and modules with the next higher
comparison of two instruments, one of which is a
certified standard of known accuracy, to detect and
b. Functional Group. Column 2 lists the next higher
adjust any discrepancy in the accuracy of the instrument
assembly group and the item names of components,
assemblies, subassemblies, and modules within the
group for which maintenance is authorized.
g. Install. The act of em placing, seating, or fixing
into position an item, part,