TM55-2840-251-23
APPENDIX B
Section I INTRODUCTION (Continued)
j. Overhaul. The maintenance effort (service/action) necessary to restore an item to a completely
serviceable/operational condition as prescribed by maintenance standards (i.e. DMWR) in the appropriate technical
publication. Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not
normally return an item to like new condition.
k. Rebuild. Consists of those services/actions necessary for the restoration of unserviceable equipment to a like
new condition in accordance with original manufacturing standards. Rebuild is the highest degree of materiel
maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero, those age
measurements (hours/miles, etc.) considered in classifying Army equipments/components.
B-4 STANDARD GROUPS
The standard groupings shown below are used, as applicable, throughout this MAC. Maintenance manuals and
RPSTLs will reflect these standard groupings as individual chapters with sections in each chapter relative to the
individual complete systems, subsystems, modules, components, assemblies, or specific parts noted.
B-5 SYMBOLS
The letters "AVUM, AVIM, and DEPOT" as placed on the Maintenance Allocation Chart indicate the level of
Maintenance responsible for performing the particular maintenance function based upon assigned skills, tools and test
equipment and time required to accomplish maintenance.
B-6 FUNCTIONAL GROUPS
GROUP
NUMBER
DESCRIPTION
0400
ENGINE SYSTEM
0401
ENGINE GENERAL
Servicing, handling, inspection requirements, lubrication charts, overhaul & retirement
schedules. (As applicable).
0402
COMPRESSOR SECTION
Rotor, blades, vanes, impeller, stators, inlet guide vanes, main frame, particle separator, bleed
valve, bearings, seals, external lines & hoses.
B-5
