TM 55-4920-403-20&P
A P P E N D I X B
M A I N T E N A N C E A L L O C A T I O N C H A R T
S e c t i o n I . I N T R O D U C T I ON
B-1. General.
g.
Install. The act of emplacing, seating or
a.
This section provides a general expla-
fixing into position an item, part, or module (com-
onation of all maintenance and repair functions au-
ponent or assembly) in a manner to allow the
thorized at various maintenance levels.
proper functioning of an equipment or system.
b. The maintenance allocation chart (MAC)
in Section II designates overall responsibility for
the performance of maintenance functions on the
identified end item or component. The imple-
mentation of the maintenance functions upon the
end item or component will be consistent with the
assigned maintenance functions.
B-2. Maintenance Functions.
a. Inspect. To determine the serviceability of
an item by comparing its physical, mechanical
and/or electrical characteristics with established
standards through examination.
b. Test. To verify serviceability and detect in-
cipient failure by measuring the mechanical or
electrical characteristics or an item and com-
paring those characteristics with prescribed stan-
dards,
c. Service. Operations required periodically
to keep an item in proper operating condition, i.e.,
to clean (decontaminate), preserve, drain, paint,
or replenish fuel, lubricants, hydraulic fluids, or
compressed air supplies.
cf. Adjust. To maintain, within prescribed lim-
its, by bringing into or exact position, or by set-
ting the operating characteristics to specified pa-
rameters.
e.
Align. To adjust specified variable ele-
ments of an item to bring about optimum or de-
sired performance.
f. Calibrate. To determine and cause cor-
rections to be made or to be adjusted on instru-
ments or test, measuring and diagnostic equip-
ment 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.
h. Replace. The act of substituting a ser-
viceable like part, subassembly or module (com-
ponent or assembly) for an unserviceable coun-
terpart.
i.
Repair. The application of maintenance
services or other maintenance actions to 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. That maintenance effort (ser-
vices/actions) necessary to restore an item to a
completely
serviceable/operational
conditional
prescribed by maintenance standards (i. e.,
DMWR) in appropriate technical publications.
Overhaul is normally the highest degree of main-
tenance performed by the Army. Overhaul does
not normally return an item to like new condition.
k. Rebuild. Consists of those services/ac-
tions necessary for the restoration of un-
serviceable equipment to a like new condition in
accordance with original manufacturing stan-
dards. Rebuild is the highest degree of material
maintenance applied to Army equipment. The re-
build 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 Maintenance
Allocation Chart.
a. Column 1, Group Number, Column 1 lists
group numbers, the purpose of which is to iden-
tify components, assemblies, subassemblies and
modules with the next higher assembly.
B-1
