TM 9-2330-271-14&P
APPENDIX D
MAINTENANCE ALLOCATION CHART
Section I. INTRODUCTION
and adjust any discrepancy in the accuracy of the
instrument being compared.
D-1. General
g. Install. The act of emplaclng, seating, or fixing
into position an item, part, or module (component or
a. This section provides a general explanation of all
assembly) in a manner to allow the proper functioning of
maintenance and repair functions authorized at various
an equipment or system.
maintenance categories.
h. Replace. The act of substituting a serviceable
b. The Maintenance Allocation Chart (MAC) in
like type part, subassembly, or module (component or
section II designates overall responsibility for the
assembly) for an unserviceable counterpart.
performance of maintenance functions on the identified
i. Repair. The application of maintenance services
end item or component. The implementation of the
or other maintenance actions to restore serviceability to
maintenance functions upon the end item or component
an item by correcting specific damage, fault, malfunction,
will be consistent with the assigned maintenance
or failure in a part, subassembly, module (component or
functions.
assembly), end item or system.
c. Section III lists the special tools and test
j. Overhaul. That maintenance effort (service/
equipment required for each maintenance function as
action) necessary to restore an item to a completely
referenced from section II.
serviceable/operational condition as prescribed by
d. Section IV contains supplemental instructions
maintenance standards in appropriate technical
and explanatory notes for a particular maintenance
publications (i.e., DMWR). Overhaul is normally the
function.
highest degree of maintenance performed by the Army.
Overhaul does not normally return an item to like new
D-2. Maintenance functions.
condition.
k. Rebuild. Consists of those services/actions
Maintenance functions will be limited to and defined as
necessary for the restoration of serviceable equipment to
follows: (except for ammunition MAC).
a like new condition in accordance with original
a. Inspect. To determine the serviceability of an
manufacturing standards. Rebuild is the highest degree
item by comparing its physical, mechanical, and/ or
of materiel maintenance applied to Army equipment.
electrical characteristics with established standards
The rebuild operation includes the act of returning to zero
through examination.
those age measurements (hours/miles, etc) considered
b. Test. To verify serviceability by measuring the
in classifying Army equipments/components.
mechanical or electrical characteristics of an item and
comparing those characteristics with prescribed
D3. Explanation of Columns in the MAC, Section II
standards.
c. Service. Operations required periodically to
a. Column 1, Group Number Column 1 lists
keep an item in proper operating conditions; i.e., to
functional group code numbers, the purpose of which is
clean (includes decontaminate, when required), to
to identify components, assemblies, subassemblies, and
preserve, to drain, to paint, or to replenish fuel,
modules with the next higher assembly.
lubricants, chemical fluids, or gases.
b. Column 2, Component/Assembly Column 2
d. Adjust. To maintain, within prescribed limits, by
contains the names of components, assemblies,
bringing into proper or exact position, or by setting the
subassemblies, and modules for which maintenance is
operating characteristics to specified parameters.
authorized.
e. Aline. To adjust specified variable elements of
an item to bring about optimum or desired performance.
f. Calibrate. To determine and cause corrections
to be made or to be adjusted on instruments or test,
measuring, and diagnostic equipments used in precision
measurement. Consists of comparisons of two
instruments, one of which is a certified standard of
known accuracy, to detect
D-1
