MAINTENANCE ALLOCATION CHART
Section I. INTRODUCTION
a. This section provides a general explanation of all maintenance and repair functions authorized at various
b. The Maintenance Allocation Chart (MAC) in Section II designates overall authority and responsibility for the
performance of maintenance functions on the identified end item or component. The application of the maintenance
functions to the end item or component will be consistent with the capacities and capabilities of the designated
c. Section III lists the tools and test equipment (both special tools and common tool sets) required for each
maintenance function as referenced from Section II.
d. Section IV contains supplementary instructions and explanatory notes for a particular maintenance function.
Maintenance functions. Maintenance functions will be limited to and defined as follows (except for ammunition
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 characteristics of an
item and comparing those characteristics with prescribed standards.
c. Service. Operations required periodically to keep an item in proper operating condition, i.e., to clean (includes
decontaminate, when required), to preserve, to drain, to paint, or to replenish fuel, lubricants, chemical fluids, or gases.
d. Adjust. To maintain or regulate, within prescribed limits, by bringing into proper or exact position, or by setting the
operating characteristics to specified parameters.
e. Align. 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 and adjust any discrepancy in the accuracy of the instrument being
g. Remove/Install. To remove and install the same item when required to perform service or other maintenance
service or other maintenance functions. Install may be the act of emplacing, 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 system.
h. Replace. To remove an unserviceable item and install a serviceable counterpart in its place. "Replace" is
authorized by the MAC and is shown as the 3rd position code of the SMR code.
Exception is authorized for ammunition MAC to permit the redesignation/redefinition of maintenance
function headings to more adequately identify ammunition maintenance functions. The heading designations and
definitions will be included in the appropriate technical manual for each category of ammunition.