NAVELEX EE 181-AA-OMI-13A/E121 R1861-T1257
b. PART NUMBER INDEX. Part numbers in this index are listed by part number in ascending alphanumeric
sequence (i.e., vertical arrangement of letter and number combination which places the first letter or digit of
each group in order A through Z, followed by the numbers 0 through 9 and each following letter or digit in
(1) FSCM column. The Federal Supply Code for Manufacturer (FSCM) is a 5-digit numeric code used to
identify the manufacturer, distributor, or Government agency, etc., that supplies the item.
(2) PART NUMBER column. Indicates the primary number used by the manufacturer (individual, firm,
corporation, or Government activity), which controls the design and characteristics of the item by
means of its engineering drawings, specifications standards, and inspection requirements to identify an
item or range of items.
(3) STOCK NUMBER column. This column lists the NSN for the associated part number and
manufacturer identified in the PART NUMBER and FSCM columns to the left.
(4) FIG. column. This column lists the number of the figure where the item is identified/located in
Sections II and III.
(5) ITEM column. The item number is that number assigned to the item as it appears in the figure
referenced in adjacent figure number column.
5. SPECIAL INFORMATION
Usable On Code. T h e u s a b l e o n c o d e a p p e a r s i n t h e l o w e r l e f t c o r n e r o f t h e D e s c r i p t i o n
Column heading. U s a b l e o n c o d e s a r e s h o w n a s " U O C : . . . . " i n t h e D e s c r i p t i o n C o l u m n
(justified left) on the first line applicable item description/nomenclature.
Uncoded items are applicable to all models. Identification of the usable on codes
used in the RPSTL are:
The usable on codes used in the RPSTL are:
6. HOW TO LOCATE REPAIR PARTS.
a. When National Stock Number or Part Number is NOT Known.
(2) First. Using the table of contents, determine the assembly group or subassembly group to which the
item belongs. This is necessary since figures are prepared for assembly groups and subassembly
groups, and listings are divided into the same groups.
(2) Second. Find the figure covering the assembly group or subassembly group to which the item belongs.
(3) Third. Identify the item on the figure and note the item number.
(4) Fourth. Refer to the Repair Parts List for the figure to find the part number for the item number
noted on the figure.
(5) Fifth. Refer to the Part Number Index to find the NSN, if assigned.