Maintenance Allocation Chart (MAC)
The Army Maintenance System (AMS)
This introduction provides a general explanation of all maintenance and repair functions
authorized at the two maintenance levels under the Two-Level Maintenance System concept.
The MAC (immediately following the introduction) 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 shall be consistent with
the capacities and capabilities of the designated maintenance levels, which are shown on the
MAC in column 4 as:
includes two subcolumns, Unit C (operator/crew), O (unit/organizational
maintenance), and Direct Support (F) maintenance.
includes two subcolumns, general support (H) and depot (D).
The tools and test equipment requirements (immediately following the MAC) list the tools and test
equipment (both special tools and common tool sets) required for each maintenance function as
referenced from the MAC.
The remarks (immediately following the tools and test equipment requirements) contain
supplemental instructions and explanatory notes for a particular maintenance function.
Maintenance functions are limited to and defined as follows:
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).
Test. To verify serviceability by measuring the mechanical, pneumatic, hydraulic, or electrical
characteristics of an item and comparing those characteristics with prescribed standards on a
scheduled basis, i.e., load testing of lift devices and hydrostatic testing of pressure hoses.
Service. Operations required periodically to keep an item in proper operating condition, e.g.,
to clean (includes decontaminate, when required), to preserve, to drain, to paint, or to
replenish fuel, lubricants, chemical fluids, or gases.
Adjust. To maintain or regulate, within prescribed limits, by bringing into proper position, or
by setting the operating characteristics to specified parameters.
Align. To adjust specified variable elements of an item to bring about optimum or desired
Calibrate. To determine and cause corrections to be made or to be adjusted on instruments
of test, measuring, and diagnostic equipment used in precision measurement. Consists of