TM 55-1680-358-12 & P
3-20. Listing of Similar Assemblies. When similar
assemblies contain approximately ninety percent or
more identical parts, the assemblies are combined and
listed as follows. Otherwise the assemblies are listed
All assemblies (figure and index numbers, part
numbers, descriptions, quantities, codes) are listed first,
followed by the detail parts.
A part common to all assemblies in the same
quantity is listed once.
A part common to all assemblies in different
quantities is listed once for each quantity. It is also
identified as to which assembly each listing pertains.
Peculiar parts are listed once. They are also
identified by a usable on code as to which assembly
3-21. Maintenance Parts List. The following
information applies to the Maintenance Parts List.
(FSCM). Federal Supply Codes for Manufacturers
(FSCM) are listed in the FSCM column. All code
numbers are in accordance with the Federal Supply
Code for Manufacturers Cataloging Handbook H4-1 and
Units per Assembly Column. The listings in this
column indicate the quantity of parts required per next
higher assembly. The abbreviation REF indicates that
the part is listed for reference purposes only.
Usable On Code. The usable on code column
contains codes to indicate the configurations of similar
assemblies listed in and illustrated by a common
breakdown. Commonly it is used to differentiate
between components of leftand righ-hand assemblies.
The absence of a usable on code in this column
3-22. Numerical Index. This index contains an alpha-
Maintenance Parts List.
3-23. Visual Index. Figure 3-1 provides an assembled
view of the Helicopter Helicopter Internal Cargo
Handling System Assembly. A description of each
major component is provided. Also included are figure
numbers in which that component is broken down.
Opposite hand assemblies are shown in the same
3-24. How To Use This Illustrated Parts Breakdown.
Refer to the following page for instructions in using the
Illustrated Parts Breakdown.