Items with these codes are not to be requested/requisi-
tioned individually, The parts that make up the assembled
item must be requisitioned or fabricated and assembled at
the level of maintenance indicated by the source code. If
the 3d position code of the SMR code authorizes you to
replace the item, but the source code indicates the items
are assembled at a higher level, order the item from the
higher level of maintenance.
XA Do not requisition XA -coded item. Order its next higher assembly.
(Also, refer to the NOTE below,)
XB If an XB item is not available from salvage, order it using the FSCM and
part number given.
XC Installation drawing, diagram, instruction sheet, field service drawing, that
is identified by manufacturers part number,
XD Item is not stocked, Order an XD coded item through normal supply
channels using the FSCM and part number given, if no NSN is available.
Cannibalization or controlled exchange, when authorized, may be
used as a source of supply for items with the above source codes,
except for those source coded XA or those aircraft support items
restricted by requirements of AR 7501.
Maintenance Code. Maintenance codes tells you the Ievel(s) of mainte-
nance authorized to USE and REPAIR support items. The maintenance
codes are entered in the third and fourth positions of the SMR code as fol-
The maintenance code entered in the third position tells you the low-
est maintenance level authorized to remove, replace, and use an
item. The maintenance code entered in the third position will indicate
authorization to one of the following levels of maintenance.
C -Crew or operator maintenance done within organizational or aviation unit
O -Organizational or aviation unit category can remove, replace, and use the