TM 55-2840-241-23
A P P E N D I X
B
MAINTENANCE ALLOCATION CHART
Section I.
INTRODUCTION
B-1. Maintenance Allocation Chart
a. This Maintenance Allocation Chart (MAC) as-
signs maintenance functions in accordance with the
Three Levels of Maintenance concept for army air-
craft. These maintenance levels, Aviation Unit
M a i n t e n a n c e ( A V U M ) ; A v i a t i o n I n t e r m e d i a t
Maintenance (AVIM) and Depot Maintenance are
depicted on the MAC as:
AVUM which corresponds to the O Code in the
RPSTL
AVIM which corresponds to an F Code in the
RPSTL
DEPOT which corresponds to a D Code in the
RPSTL
b. The maintenance to be performed below depot
and in the field is described as follows:
(1) Aviation Unit Maintenance (AVUM) ac-
tivities will be staffed and equipped to perform high
frequency
On-Aircraft maintenance tasks re-
quired to retain or return aircraft to a serviceable
condition. The maintenance capability of the
AVUM will be governed by the Maintenance Allo-
cation Chart (MAC) and limited by the amount and
complexity of ground support equipment (GSE), fa-
cilities required, and number of spaces and critical
skills available. The range and quantity of author-
ized spare modules/components will be consistent
with the mobility requirements dictated by the air
mobility concept. (Assignments of maintenance
tasks to divisional company size aviation units will
consider the overall maintenance capability of the
division, the requirement to conserve personnel and
equipment resources and air mobility require-
ments.)
(a) Company size Aviation Units perform
those tasks which consist primarily of preventive
maintenance and maintenance repair and replace-
ment functions associated with sustaining a high
level of aircraft operational readiness. Perform
maintenance inspections and servicing to include
preflight, daily, intermediate, periodic and special
inspections as authorized by the MAC or higher
headquarters. Identify the cause of equipment/sys-
tem malfunctions using applicable technical man-
u a l t r o u b l e s h o o t i n g i n s t r u c t i o n s , b u i l t - i n - t e s
equipment (BITE), installed aircraft instruments,
or easy to use/interpret diagnostic/fault isolation
devices (TMDE). Replace worn or damaged mod-
ules/components which do not require complex ad-
justments or system alignment and which can be
removed/installed with available skills, tools and
equipment. Perform operational and continuity
checks and make minor repairs to the electrical sys-
tem. Inspect, service and make operational capacity
and pressure checks to hydraulic systems. Perform
servicing, functional adjustments, and minor re-
pair/replacement to the flight control, propulsion,
power train and fuel systems. Accomplish airframe
repair which does not require extensive disassem-
bly, jigging, or alignment. The manufacture of air-
frame parts will be limited to those items which can
be fabricated with tools and equipment found in
current air mobile tools and shop sets. Evacuate un-
serviceable modules/components and end items be-
yond the repair capability of AVUM to the support-
ing AVIM.
(b) Less than Company Size Aviation
Units: Aviation elements organic to brigade, group,
battalion, headquarters and detachment size units
are normally small and have less than ten aircraft
assigned. Maintenance tasks performed by these
units will be those which can be accomplished by
the aircraft crew chief or assigned aircraft repair-
man and will normally be limited to preventive
maintenance, inspections, servicing, spot painting,
stop drilling, application of nonstress patches,
minor adjustments, module/component fault diag-
nosis and replacement of selected modules/com-
ponents, Repair functions will normally be accom-
plished by the supporting AVIM unit.
(2) A v i a t i o n I n t e r m e d i a t e M a i n t e n a n c
(AVIM) provides mobile, responsible One Stop
m a i n t e n a n c e s u p p o r t . ( M a i n t e n a n c e f u n c t i o n
which are not conducive to sustaining air mobility
will be assigned to depot maintenance). Performs
all maintenance functions authorized to be done at
AVUM. Repair of equipment for return to user will
emphasize support or operational readiness require-
ments. Authorized maintenance includes replace-
ment and repair of modules/components and items
which can be accomplished efficiently with avail-
C h a n g e 5 B -
