Appendix B: MAINTENANCE ALLOCATION CHART THREE LEVELS OF MAINTENANCE CONCEPT

TM 55-4920-405-13&P

APPENDIX B

MAINTENANCE ALLOCATION CHART

THREE LEVELS OF MAINTENANCE CONCEPT

B-1. MAINTENANCE ALLOCATION CHART.

modules/components and end items beyond the re-

pair capability of AVUM to the supporting AVIM.

a. This Maintenance Allocation Chart (MAC) as-

(b) Less than Company Size Aviation Units:

signs maintenance functions in accordance with the

Three Levels of Maintenance concept for army air-

Aviation elements organic to brigade, group, battalion

headquarters and detachment size units are normally

craft. These maintenance levels, Aviation Unit

small and have less than ten aircraft assigned.

Maintenance (AVUM): Aviation Intermediate Main-

tenance (AVIM) and Depot Maintenance are depicted

Maintenance tasks performed by the aircraft crew

on the MAC as:

chief or assigned aircraft repairman and will

normally be limited to preventive maintenance, in-

O - AVUM

spections, servicing, spot painting, stop drilling,

F - AVIM

application of nonstress patches, minor adjustments,

module/component fault diagnosis and replacement

D - DEPOT

of selected modules/components. Repair functions

b. The maintenance to be performed below depot

will normally be accomplished by the supporting

AVIM unit.

and in the field is described as follows.

(2) Aviation Intermediate Maintenance (AVIM) -

(1) Aviation Unit Maintenance (AVUM) - AVUM

AVIM provides mobile, responsive "One Stop" main-

activities will be staffed and equipped to perform high

tenance support. (Maintenance functions which are

frequency "On-Equipment maintenance tasks re-

not conducive to sustaining air mobility will be as-

quired to retain or return equipment to a serviceable

signed to depot maintenance.) Performs all main-

condition. The maintenance capability of the AVUM

tenance functions authorized to be done at AVUM.

will be governed by the Maintenance Allocation

Repair of equipment for return to user will emphasize

Chart (MAC) and limited by the amount and com-

support or operational readiness requirements.

plexity of support equipment, facilities required,

Authorized maintenance includes replacement and

and number of spaces and critical skills available.

The range and quantity of authorized spare modules/

repair of modules/components and end items which

components will be consistent with the mobility re-

can be accomplished efficiently with available skills,

quirements dictated by the air mobility concept.

tools, and equipment. Establishes the Direct Ex-

(Assignment of maintenance tasks to divisional

change (DX) program for AVUM units by repairing

company size aviation units will consider the overall

selected items for return to stock when such repairs

maintenance capability of the division, the require-

cannot be accomplished at the AVUM level. Inspects,

ment to conserve personnel and equipment resources

t r o u b l e s h o o t s , tests, diagnoses, repairs, adjusts,

calibrates, and aligns system modules/components.

and air mobility requirements.)

Module/component disassembly and repair will sup-

port the DX program and will normally be limited to

(a) Company Size Aviation Units: Perform

tasks requiring cleaning and the replacement of

those tasks which consist primarily of preventive

seals, fittings and items of common hardware. Un-

maintenance and maintenance repair and replace-

serviceable reparable modules/components and end

ment functions associated with sustaining a high level

items which are beyond the capability of AVIM to

of equipment operational readiness. Perform main-

repair will be evacuated to Depot Maintenance.

tenance inspections and servicing to include daily,

This level will perform special inspections which

intermediate, periodic and special inspections as

exceed AWM capability. Provides quick response

authorized by the MAC or higher headquarters.

maintenance support, on-the-job training, and

Identify the cause of equipment/system malfunctions

technical assistance through the use of mobile main-

using applicable technical manual troubleshooting

tenance contact teams. Maintains authorized opera-

instructions, built-in-test equipment (BITE), in-

tional readiness float. Provides collections and

stalled instruments, or easy to use/interpret

classification services for serviceable/unservice-

diagnostic/fault isolation devices (TMDE). Replace

able material. Operates a cannibalization activity

worn or damaged modules/components which do not

i n accordance with AR 750-50. (The aircraft

require complex adjustments or system alignment

maintenance company within the maintenance bat-

and which can be removed/installed with available

skills, tools and equipment. Perform operational

talion of a division will perform AVIM functions

consistent with air mobility requirements and con-

and continuity checks and make minor repairs.

s e r v a t i o n of personnel and equipment resources.

Perform servicing, functional adjustments, and

Additional intermediate maintenance support will

m i n o r repair/replacement. Evacuate unserviceable

B-1