This manual lists spares and repair parts; special
XB Item is not procured or stocked. If not availa-
tools; special test, measurement, and diagnostic
ble through salvage, requisition.
equipment (TMDE), and other special support equip-
ment required for performance of organizational, di-
Cannibalization or salvage may be used as
rect support, and general support maintenance of the
a source of supply for any items source
AN/TNH-23A. It authorizes the requisitioning and
coded above except those coded XA and
issue of spares and repair parts as indicated by the
aircraft support items as restricted by AR
source and maintenance codes.
(2) Maintenance code. Maintenance codes are
assigned to indicate the levels of maintenance au-
This Repair Parts and Special Tools List is divided
thorized to USE and REPAIR support items. The
into the following sections:
maintenance codes are entered in the third and
a. Section II. Repair Parts List. A list of spares
fourth positions of the Uniform SMR Code format as
and repair parts authorized for use in the perform-
ance of maintenance. The list also includes parts
(a) The maintenance code entered in the third
which must be removed for replacement of the au-
position will indicate the lowest maintenance level
thorized parts. Parts lists are composed of functional
authorized to remove, replace, and use the support
groups in numeric sequence, with the parts in each
item. The maintenance code entered in the third posi-
group listed in figure and item number sequence.
tion will indicate one of the following levels of mainte-
b. Section III. Special Tools List. Not applicable.
c. Section IV. National Stock Number and Part
Number Index. A list, in National item identification
0 Support item is removed, replaced, used at the
number (NIIN) sequence, of all National stock num-
bers (NSN) appearing in the listings, followed by a
H Support item is removed, replaced, used at the
list, in alphameric sequence, of all part numbers ap-
general support level.
pearing in the listings. National stock numbers and
D Support items that are removed, replaced, used
part numbers are cross-referenced to each illustra-
at depot, mobile depot, specialized repair ac-
tion figure and item number appearance.
3. Explanation of Columns
(b) The maintenance code entered in the fourth
position indicates whether the item is to be repaired
a Illustration. This column is divided as follows:
and identifies the lowest maintenance level with the
(1) Figure number. Indicates the figure number
capability to perform complete repair (i.e., all author-
of the illustration on which the item is shown.
ized maintenance codes:
(2) Item number, The number used to identify
item called out in the illustration.
b. Source, Maintenance, and Recoverability (SMR)
O The lowest maintenance level capable of com-
plete repair of the support item is the organiza-
(1) Source code. Source codes indicate the man-
ner of acquiring support items for maintenance, re-
H-- The lowest maintenance level capable of com-
pair, or overhaul of end items. Source codes are en-
plete repair of the support item is the general
tered in the first and second positions of the Uniform
SMR Code format as follows:
D-- The lowest maintenance level capable of com-
plete repair of the support item is the depot
PA Item procured and stocked for anticipated or
Z Nonreparable. No repair is authorized.
XA Item is not procured or stocked because the
(3) Recoverability code. Recoverability codes
are assigned to support items to indicate the disposi-
requirements for the item will result in the
tion action on unserviceable items, The recoverabil-
replacement of the next higher assembly.