MAINTENANCE ALLOCATION CHART (MAC)
Section 1. INTRODUCTION
B-1. The Army Maintenance System MAC.
a. This introduction (Section I) provides a gen-
eral explanation of all maintenance and repair func-
tions authorized at various maintenance levels under
the standard Army Maintenance System concept.
b. The Maintenance Allocation Chart (MAC) in
Section II designates overall authority and responsibil-
ity for the performance of maintenance functions on
the Identified end item or component. The application
of the maintenance functions to the end item or com-
ponent will be consistent with the capacities and capa-
bilities of the designated maintenance levels, which
are shown on the MAC in column (4) as:
Unit - includes two subcolumns, C (opera-
tor/crew) and O (unit) maintenance.
Direct Support includes an F subcolumn.
General Support - includes an H subcolumn.
Depot - includes a D subcolumn
c. Section III lists the tools and test equipment
(both special tools and common tool sets) required for
each maintenance function as referenced from sec-
d. Section IV contains supplemental instructions
and explanatory notes for a particular maintenance
B-2. MAINTENANCE FUNCTIONS. Maintenance
functions are limited to and defined as follows: (see
18.104.22.168g for ammunition MAC exception)
a. Inspect. To determine the serviceability of an
item by comparing its physical, mechanical, and/or
electrical characteristics with established standards
through examination (e.g.. by sight, sound. or feel)
b. Test. To verify serviceability by measuring the
mechanical, pneumatic, hydraulic, or electrical charac-
teristics of an item and comparing those charac-
teristics with prescribed standards.
c. Service. Operations required periodically to
keep an item in proper operating condition, e.g., to
clean (includes decontaminate, when required), to pre-
serve, to drain, to paint, or to replenish fuel. lubri-
cants, chemical fluids, or gases.
d. Adjust. To maintain or regulate, within pre-
scribed Iimits, by bringing into proper or exact posi-
tion, or by setting the operating characteristics to
e. Align. To adjust specified variable elements
of an item to bring about optimum and desired per-
f. Calibrate. To determine and cause correction
to be made or to be adjusted on instruments or test,
measuring, and d/agnostic equipment used in preci-
sion measurement. Consists of comparisons of two in
struments, one of which is a certified standard of
known accuracy, to detect and adjust any discrep-
ancy in the accuracy of the instrument being come
g. Remove / Install. To remove and install the
same item when required to perform service or other
maintenance functions install may be the act of em-
placing, seating, or fixing into position a spare, repair
part, or module (component or assembly) in a manner
to allow the proper functioning of an equipment or sys-
h. Replace. To remove an unserviceable item
and install a serviceable counterpart in its place. Re-
place is authorized by the MAC and the assigned
maintenance level is shown as the 3rd position code
of the SMR code.