TM 55-4920-404-30&P
MAINTENANCE ALLOCATION CHART
INTRODUCTION
Section I.
like part, subassembly or module (component or as-
B-1. GENERAL.
sembly) for an unserviceable counterpart.
a. This section provides a general explanation of
i. Repair. The application of maintenance ser-
all maintenance and repair functions authorized at
vices or other maintenance actions to restore ser-
various maintenance levels.
viceability to an item by correcting specific damage,
b. The Maintenance Allocation Chart (MAC) in
fault, malfunction or failure in a part, subassembly,
Section II designates overall responsibility for the
module (component or assembly), end item or sys-
performance of maintenance functions on the iden-
tem.
tified end item or component. The implementation
j. Overhaul. That maintenance effort (services/
of the maintenance functions upon the end item or
actions) necessary to restore an item to a com-
component will be consistent with the assigned
pletely serviceable/operational condition as pre-
maintenance functions.
scribed by maintenance standards (i.e., DMWR) in
B-2. MAINTENANCE FUNCTIONS.
appropriate technical publications. Overhaul is nor-
a. Inspect. To determine the serviceability of an
mally the highest degree of maintenance performed
item by comparing its physical, mechanical and/or
by the Army. Overhaul does not normally return an
electrical characteristics with established stan-
item to like new condition.
dards through examination.
k. Rebuild. Consists of those servires/actions
b. Test. To verify serviceability and detect incip-
necessary for the restoration of unserviceable
ient failure by measuring the mechanical or elec-
equipment to a like new condition in accordance
trical characteristics or an item and comparing
with original manufacturing standards. Rebuild is
those characteristics with prescribed standards.
the highest degree of material maintenance applied
to Army equipment. The rebuild operation includes
c. Service. Operations required periodically to
the act of returning to zero those age measurements
keep an item in proper operating condition, i.e., to
(hours/miles, etc.) considered in classifying Army
clean (decontaminate), preserve, drain, paint, or re-
equipments/components.
plenish fuel, lubricants, hydraulic fluids, or com-
pressed air supplies.
B-3. EXPLANATION OF COLUMNS IN THE
MAINTENANCE ALLOCATION CHART.
d. Adjust. To maintain, within prescribed lim-
its, by bringing into or exact position, or by setting
a. Column 1, Group Number. Column 1 lists
the operating characteristics to specified parame-
group numbers, the purpose of which is to identify
ters.
components, assemblies, subassemblies and mod-
ules with next higher assembly.
e. Align. To adjust specified variable elements
of an item to bring about optimum or desired per-
b. Column 2, Component/Assembly. Column 2
formance.
contains the name of components, assemblies, sub-
assemblies and modules for which maintenance is
f. Calibrate. To determine and cause cor-
authorized.
rections to be made or to be adjusted on instruments
or test, measuring and diagnostic equipment used
Column
C. Column 3, Maintenance Functions.
in precision measurement. Consists of comparisons
3 lists the functions to be performed on the item
of two instruments, one of which is a certified stan-
listed in Column 2. (For detailed explanation of
dard of known accuracy, to detect and adjust any
these functions, see paragraph B-2).
discrepancy in the accuracy of the instrument being
d. Column 4, Maintenance Level. Column 4
compared.
specifies, by the listing of a "work time" figure in
g. Install. The act of emplacing, seating or fix-
the appropriate subcolumn(s), the lowest level of
ing into position an item, part, or module (com-
maintenance authorized to perform the function
ponent or assembly) in a manner to allow the proper
listed in Column 3. This figure represents the active
functioning of an equipment or system.
time required to perform the maintenance function
at the indicated level of maintenance. If the number
h. Replace. The act of substituting a serviceable
B-1
