i. Repair. The application of maintenance services including fault location/troubleshooting, removal/installa-
tion, 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.
j. Overhaul. The maintenance effort (service/action) prescribed to restore an item to a completely serviceable/
operational condition as required by maintenance standards in appropriate technical publications (i.e., DMWR).
Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not normally return
an item to like new condition.
k. Rebuild. Consists of those service/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 (hours, miles, etc.) considered in classifying Army equipments/components.
B-3. Explanation of Columns in the MAC, Section II.
a. Column 1, Group Number. Column 1 lists functional group code numbers, the purpose of which is to identify
maintenance significant components, assemblies, subassemblies, and modules with the next higher assembly. End
item group number shall be 00.
b. Column 2, Component/Asssembly. Column 2 contains the names of components, assemblies, subassemblies,
and modules for which maintenance is authorized.
c. Column 3, Maintenance Function. Column 3 lists the functions to be performed on the item listed in Column
2. (For detailed explanation of these functions, see paragraph B-2.).
d. Column 4, Maintenance Category. Column 4 specifies, by the listing of a work time figure in the appropriate
subcolumn(s), the category of maintenance authorized to perform the function listed in Column 3. This figure
represents the active time required to perform that maintenance function at the indicated category of maintenance.
If the number or complexity of the tasks within the listed maintenance function vary at different maintenance
categories, appropriate work time figures will be shown for each category. 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/quality control
time in addition to the time required to perform the specific tasks identified for the maintenance functions authorized
in the maintenance allocation chart. The symbol designations for the various maintenance categories areas follows:
Aviation Unit Maintenance
Aviation Intermediate Maintenance
e. Column 5, Tools and Equipment. Column 5 specifies, by code, those common tool sets (not individual tools)
and special tools, TMDE, and support equipment required to perform the designated function.
f. Column 6, Remarks. This column shall, when applicable, contain a letter code, in alphabetic order, which
shall be keyed to the remarks contained in Section IV.