Appendix B. MAINTENANCE ALLOCATION CHART

TM 55-4920-411-13&P

APPENDIX B

MAINTENANCE ALLOCATION CHART

INTRODUCTION

Section 1.

B-1. MAINTENANCE ALLOCATION CHART.

inspections and servicing to include daily, intermedi-

ate, periodic and special inspections as authorized by

a. This Maintenance Allocation Chart (MAC) as-

the MAC or higher headquarters. Identify the cause of

signs maintenance functions in accordance with the

equipment/system m a l f u n c t i o n s u s i n g a p p l i c a b l e

Three Levels of Maintenance concept for army aircraft.

technical manual troubleshooting instructions, Built-In-

These maintenance levels: Aviation Unit Maintenance

Test Equipment (BITE), installed instruments. or easy

(AVUM), Aviation Intermediate Maintenance

to use Test Measurement and Diagnostic Equipment

(AVIM) and Depot Maintenance are depicted on the

(TMDE). Replace worn or damaged modules/compo-

MAC as:

nents which do not require complex adjustments or

system alignment and which can be removed /installed

AVUM WHICH CORRESPONDS TO THE 0

with available skills, tools and equipment. Perform

CODE IN THE REPAIR PARTS AND SPECIAL

operational and continuity checks and make minor

TOOLS LIST (RPSTL)

repairs. Perform servicing, functional adjustments, and

AVIM WHICH CORRESPONDS TO THE F CODE

minor repair/replacement. Evacuate unserviceable

IN THE REPAIR PARTS AND SPECIAL TOOLS

modules/components and end items beyond the repair

LIST ( RPSTL:)

capability of AVUM to the supporting AVIM.

DEPOT WHICH CORRESPONDS TO THE D

(b) Less than Company Size Aviation Units:

CODE IN THE REPAIR PARTS AND SPECIAL

Aviation elements organic to brigade, group, battalion

TOOLS LIST (RPSTL)

headquarters and detachment size units are normally

small and have less than ten aircraft assigned. Main-

b. The maintenance to be performed below depot

tenance tasks performed by the aircraft crew chief or

and in the field is described as follows:

assigned aircraft repairman will normally be limited to

(1) Aviation Unit Maintenance ( A V U M ) -

preventive maintenance, inspections, servicing, spot

A V U M activities will be staffed and equipped to

painting, stop drilling, minor adjustments, module/

perform high frequency "On-Equipment" mainte-

component fault diagnosis and replacement of selected

nance tasks required to retain or return equipment to a

modules/components. Repair functions wil normally

serviceable condition. The maintenance capability of

be accomplished by the supporting AVIM unit.

the AVUM will be governed by the MAC and limited

by the amount and complexity of support equipment,

B-2. USE OF THE MAINTENANCE ALLOCATION

facilities required, and number of spaces and critical

CHART.

skills available. The range and quantity of authorized

spare modules/components will be consistent with the

a. The MAC assigns maintenance functions to the

mobility requirements dictated by the air mobility

lowest level of maintenance based on past experience

concept. (Assignment of maintenance tasks to divi-

and the following consideration:

sional company size aviation units will consider the

(1) SkiIls available.

overall maintenance capability of the division, the

requirement to conserve personnel and equipment

(2) Time required.

resources and air mobility requirements).

(3) Tools and test equipment required and/or

(a) Company Size Aviation Units: Perform

available.

those tasks which consist primarily of preventive

b. Only the lowest level of maintenance authorized

maintenance and maintenance repair and replacement

to perform a maintenance function is indicated. If the

functions associated with sustaining a high level of

lowest level of maintenance cannot perform all tasks of

equipment operational readiness. Perform maintenance

B-1