APPENDIX D MAINTENANCE ALLOCATION CHART

TM 10-3930-242-12

APPENDIX D

MAINTENANCE ALLOCATION CHART

Section I. INTRODUCTION

e. Aline. To adjust specified variable elements

D-1. General

of an item to bring about optimum or desired

a. This section provides a general explanation of

performance.

all maintenance and repair functions authorized at

various maintenance categories.

f. Calibrate. To determine and cause corrections

to be made or to be adjusted on instruments or

b. The Maintenance Allocation Chart (MAC) in

test, measuring, and diagnostic equipments used in

section II designates overall authority and responsi-

precision measurement. Consists of comparisons

bility for the performance of maintenance func-

of two instruments, one of which is a certified

tions on the identified end item or component.

standard of known accuracy, to detect and adjust

The application of the maintenance functions to

any discrepancy in the accuracy of the instrument

the end item or component will be consistent with

being compared.

the capacities and capabilities of the designated

maintenance categories.

g. Remove/Install. To remove and install the

same item when required to perform service or

c. Section III lists the tools and test equipment

other maintenance functions. Install may be the

(both special tools and common tool sets) required

act of emplacing, seating, or fixing into position a

for each maintenance function as referenced from

space, repair part, or module (component or as-

section II.

sembly) in a manner to allow the proper function-

d. Section IV contains supplemental instructions

ing of an equipment or system.

and explanatory notes for a particular maintenance

function.

h. Replace. To remove an unserviceable item

D-2. Maintenance Functions. Maintenance func-

and install a serviceable counterpart in its place.

tions will be limited to and defined as follows:

"Replace" is authorized by the MAC and is shown

as the third position of the SMR code.

a. Inspect. To determine the serviceability of an

item by comparing its physical, mechanical, and/or

i. Repair.

The application of maintenance

electrical characteristics with established standards

service1, including fault location/troubleshooting2,

through examination (e.g., by sight, sound, or feel).

removal/installation, disassemble/assembly3 proce-

dures, and maintenance actions 4 to identify

b. Test. To verify serviceability by measuring

troubles and restore serviceability to an item by

the mechanical, pneumatic, hydraulic, or electrical

characteristics of an item and comparing those

correcting specific damage, fault, malfunction, or

characteristics with prescribed standards.

failure in a part, subassembly, module (component

or assembly), end item, or system.

c. Service. Operations required periodically to

keep an item in proper operating condition, i.e., to

j. 0verhaul. That maintenance effort (service/

clean (including decontaminate, when required), to

action) prescribed to restore an item to a completely

preserve, to drain, to paint, or to replenish fuel,

serviceable/operational condition as required by

lubricants, chemical fluids, or gases.

maintenance standards in appropriate technical

publication (i.e., DMWR), Overhaul is normally

d. Adjust. To maintain or regulate, within pre+

the highest degree of maintenance performed by

scribed limits, by bringing into proper or exact

the Army. Overhaul does not normally return an

position, or by setting the operating characteristics

item to like-new condition.

to specified parameters.

Service-inspect, test, service, adjust, aline, calibrate, and/or replace.

Fault locating/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 (UUT).

Diaassembly/assembly encompasses the step-by-step taking apart (or breakdown) of a spare/func-

tional group coded item to the level of its least componency identified as maintenance significant (i.e.,

assigned an SMR code) for the category of maintenance under consideration.

Action welding, grinding, reiveting, straightening, facing, remachining, and/or resurfacing.

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