a. This section provides a general explanation of all maintenance and repair functions authorized at the
various maintenance levels.
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 Ill lists the tools and test equipment (both special tools and common tool sets) required for each
d. Section IV contains supplemental instructions and explanatory notes for a particular maintenance function.
Maintenance functions will be limited to and defined as follows:
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
characterist 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. 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 d iagnostic 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 compared.
g. Remove/lnstall To remove and install the same item when required to perform 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 third position of the SMR code.
i. Repair. The application of maintenance services, including fault location/troubleshooting,
removal/Installation, and disassembly/assembly procedures and maintenance actions to identify troubles and
restore serviceability to an item by correcting specific damage, fault, malfunction, or failure in a part, subassembly,
module (component or assembly), end item, or system.