Appendix B. MAINTENANCE ALLOCATION CHART

TM 55-4940-353-13&P

APPENDIX B

MAINTENANCE ALLOCATION CHART

Section I. INTRODUCTION

level of equipment operational readiness Perform

B-1. Maintenance Allocation Chart.

maintenance inspections and servicing to include daily,

intermediate, periodic and special inspections as

a. This Maintenance Allocation Chart (MAC)

authorized by the MAC or higher headquarters Identify

assigns maintenance functions in accordance with the

the cause of equipment/system malfunctions using

Three Levels of Maintenance concept for army aircraft.

applicable technical manual troubleshooting instructions,

These maintenance levels: Aviation Unit Maintenance

Built-In-Test Equipment (BITE), installed instruments, or

(AVUM), Aviation Intermediate Maintenance (AVIM) and

easy to use Test Measurement and Diagnostic

Depot Maintenance are depicted on the MAC as

Equipment (TMDE).

Replace worn or damaged

modules/components which do not require complex

AVUM which corresponds to the O code in the Repair

adjustments or system alignment and which can be

Parts and Special Tools List (RPSTL).

removed/installed with available skills, tools and

equipment. Perform operational and continuing checks

AVIM which corresponds to the F code in the Repair

and make minor repairs. Perform servicing, functional

Parts and Special Tools List (RPSTL).

adjustments, and minor repair/replacement. Evacuate

unserviceable models/components and end items

DEPOT which corresponds to the D code in the Repair

beyond the repair capability of AVUM to the supporting

Parts and Special Tools List (RPSTL).

AVIM

b. The maintenance to be performed below depot

(b) Less than Company Size Aviation

and in the field is described as follows:

Units. Aviation elements organic to brigade, group,

battalion headquarters normally small and have less

(1) Aviation Unit Maintenance (AVUM).

than ten aircraft assigned.

Maintenance tasks

AVUM activities will be staffed and equipped to perform

performed by the aircraft crew chief or assigned aircraft

high frequency "On Equipment" maintenance tasks

repairman will normally be limited to preventive

required to retain or return equipment to a serviceable

maintenance, inspections, servicing, spot painting, stop

condition The maintenance capability of the AVUM will

drilling, minor adjustments, module/component fault

be governed by the MAC and limited by the amount and

diagnosis

and

replacement

selected

complexity of support equipment, facilities required, and

modules/components. Repair functions will normally be

number of spaces and critical skills available. The

accomplished by the supporting AVIM unit.

range

and

quantity

authorized

spare

models/components will be consistent with the mobility

(2) Aviation Intermediate Maintenance

requirements dictated by the air mobility concept

(AVIM). AVIM provides mobile, responsive "One Stop"

(Assignment of maintenance tasks to divisional

maintenance support. (Maintenance functions which are

company size aviation units will consider the overall

not conductive to sustaining air mobility will be assigned

maintenance capability of the division, the requirement

to depot maintenance)

to conserve personnel and equipment resources and air

mobility requirements)

(a) Company

Size

Aviation

Units.

Perform those tasks which consist primarily of

preventive maintenance and maintenance repair and

replacement functions associated with sustaining a high

B-1