Appendix A: AVIATION UNIT MAINTENANCE (AVUM) AND AVIATION INTERMEDIATE MAINTENANCE (AVIM) CONCEPT

TM 55-1730-219-20P

APPENDIX A

AVIATION UNIT MAINTENANCE (AVUM) AND

AVIATION INTERMEDIATE MAINTENANCE (AVIM) CONCEPT

a. This appendix explains the maintenance functions of the Three Levels of Maintenance concept for

Army aircraft. These maintenance levels, Aviation Unit Maintenance (AVUM); Aviation Intermediate Main-

tenance (AVIM); and Depot Maintenance, are shown in the third, fourth, and fifth positions of the SMR

codes of this RPSTL as:

AVUM

AVIM

DEPOT

b. The maintenance to be performed below depot level is described as follows:

(1) Aviation Unit Maintenance (AVUM). AVUM activities will be staffed and equipped to perform

high frequency "On-Aircraft" maintenance tasks required to maintain a level of aircraft readiness. The

maintenance capability of the AVUM will be governed by the Maintenance Allocation Chart (MAC) and

limited by the amount and complexity of ground support equipment (GSE), facilities, and number of per-

sonnel and critical skills available. The range and quantity of authorized spare modules/components will

be consistent with the air mobility concept.

(a) Company Size Aviation Units. These units will perform those tasks which consist pri-

marily of preventive maintenance and repair and replacement functions associated with sustaining a high

level of aircraft operational readiness. Perform maintenance inspections and servicing to include pre-

flight, daily, intermediate, periodic, and special inspections as authorized by the MAC. Identify the cause

of equipment/system malfunctions using applicable technical manual troubleshooting instructions, built-

in-test equipment (BITE), installed aircraft instruments, or easy to use/interpret diagnostic/fault isolation

devices (TMDE). Replace worn or damaged modules/ components which do not require complex adjust-

ments or system alignment and which can be removed/installed with available skills, tools, and equip-

ment. Perform operational and continuity checks and make minor repairs to the flight control, propulsion,

power train, and fuel systems. Accomplish air frame repair which does not require alignment. The manu-

facture of airframe parts will be limited to those items which can be fabricated with tools and equipment

found in current air mobile tool and shop sets. Evacuate unserviceable modules/components and end

items beyond the repair capability of AVUM to the supporting AVIM. (Assignment 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 resoruces, and air mobility requirements.

(b) Less Than Company Size Aviation Units. Aviation elements organic to brigade, group,

battalion headquarters, and detachment size units are normally small and have fewer than ten aircraft as-

signed. Maintenance tasks performed by these units will be those which can be accomplished by the air-

craft crew chief or assigned aircraft repairman and will normally be limited to preventive maintenance, in-

spections, servicing, spot painting, stop drilling. application of nonstress patches, minor adjustments,

module/component fault diagnosis and replacement of selected modules/components. Repair functions

will normally be accomplished by the supporting AVIM unit.

(2) Aviation Intermediate Maintenance (AVIM). AVIM provides mobile, maintenance support to

(Maintenance functions which are not conducive to sustaining air mobility will be assigned to

AVUM.

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 requirements. Authorized

maintenance includes replacement and repair of modules/components and end items which can be ac-