TM 1-4220-250-12&P
APPENDIX C
AVIATION UNIT MAINTENANCE
REPAIR PARTS AND SPECIAL TOOLS LIST
SECTION I. INTRODUCTION
C.1 SCOPE.
This RPSTL lists and authorizes spares and repair parts; special tools; special test, measurement,
and diagnostic equipment
(TMDE); and other special support equipment required for performance of aviation unit maintenance of the LRU-18/U. It
authorizes the requisitioning, issue, and disposition of spares, repair parts and special tools as indicated by the source,
maintenance and recoverability (SMR) codes.
C.2 GENERAL.
In addition to Section I, Introduction, this Repair Parts and Special Tools List is divided into the following sections:
a. Section II. Repair Parts List. A list of spares and repair parts authorized by this RPSTL for use in the performance
of maintenance. The list also includes parts which must be removed for replacement of the authorized parts. Parts
lists are composed of functional groups in ascending alphanumeric sequence, with the parts in each group listed in
ascending figure and item number sequence.
b. Section III. Special Tools List. A list of special tools, special TMDE, and other special support equipment
authorized by this RPSTL for the performance of maintenance.
c. Section IV. Cross-reference Indexes. A list, in National item identification number (NIIN) sequence, of all
National stock numbers (NSN) appearing in the listing, followed by a list in alphanumeric sequence of all part
numbers appearing in the listing. National stock numbers and part numbers are cross-referenced to each illustration
figure and item number appearance.
C.3 EXPLANATION OF COLUMNS (SECTIONS II AND III).
a. ITEM NO. (Column (1)). Indicates the number used to identify items called out in the illustration.
b. SMR CODE (Column (2)). The Source, Maintenance, and Recoverability (SMR) code is a 5-position code contain-
ing supply/requisitioning information, maintenance category authorization criteria, and disposition instruction, as
shown in the following breakout:
How you get an item
Who can install,
replace or use the item
Who can do complete
repair on the item
Who determined
disposition action on
an unserviceable item
Change 1
C-1
