TM 9-2350-247-20-3
MAINTENANCE ALLOCATION CHART (MAC)—Continued
0540 00
NOTE
The following definitions are applicable to the “repair” maintenance function:
• Services — Inspect, test, service, adjust, align, calibrate, and/or replace.
• Fault location/troubleshooting — The process of investigating and detecting the cause of
equipment malfunctioning; the act of isolating a fault within a system or Unit Under Test
(ET).
• Disassembly/assembly — The step-by-step breakdown (taking apart) of a spare/functional
group coded item to the level of its least component, that is assigned an SMR code for the
level of maintenance under consideration (i.e., identified as maintenance significant).
• Actions — Welding, grinding, riveting, straightening, facing, machining, and/or surfacing.
(10) Overhaul. That maintenance effort (service/action) prescribed to restore an item to a completely serviceable/
operational condition as required by maintenance standards in appropriate technical publications. Overhaul is
normally the highest degree of maintenance performed by the Army. Overhaul does not normally return an item to
like new condition.
(11) Rebuild. Consists of those services/actions necessary for the restoration of unserviceable equipment to a like new
condition in accordance with original manufacturing standards. Rebuild is the highest degree of material
maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero those age
measurements (e.g., hours/miles) considered in classifying Army equipment/components.
Explanations of Columns in the MAC
Column (1) — Group Number. Column (1) lists FGC numbers, the purpose of which is to identify maintenance significant
components, assemblies, subassemblies, and modules with the Next Higher Assembly (NHA).
Column (2) — Component/Assembly. Column (2) contains the item names of components, assemblies, subassemblies, and
modules for which maintenance is authorized.
Column (3) — Maintenance Function. Column (3) lists the functions to be performed on the item listed in column (2). (For a
detailed explanation of these functions refer to “Maintenance Functions” outlined above.)
Column (4) — Maintenance Level. Column (4) specifies each level of maintenance authorized to perform each function listed
in column (3), by indicating work time required (expressed as man-hours in whole hours or decimals) in the appropriate
subcolumn. This work time figure represents the active time required to perform that maintenance function at the indicated
level of maintenance. If the number or complexity of the tasks within the listed maintenance function varies at different
maintenance levels, appropriate work time figures are shown for each level. The work time figure represents the average time
required to restore an item (assembly, subassembly, component, module, end item, or system) to a serviceable condition under
typical field operating conditions. This time includes preparation time (including any necessary disassembly/assembly time),
troubleshooting/fault location time, and quality assurance time in addition to the time required to perform the specific tasks
identified for the maintenance functions authorized in the MAC. The symbol designations for the various maintenance levels
are as follows:
C — Operator or crew maintenance
O — Unit maintenance
F — Direct support maintenance
H — General support maintenance
D — Depot maintenance
Column (5) — Tools and Equipment Reference Code. Column (5) specifies, by code, those common tool sets (not individual
tools), common Test, Measurement and Diagnostic Equipment (TMDE), and special tools, special TMDE, and special support
equipment required to perform the designated function. Codes are keyed to the entries in the tools and test equipment table.
Column (6) — Remarks Code. When applicable, this column contains a letter code, in alphabetical order, that is keyed to the
remarks table entries.
0540 00-2
