This document provides information on the Army/Navy designation system codes. It explains that codes beginning with "AN/" refer to the Army/Navy designation system. The first letter of the three letter code indicates the installation or function, such as manned aircraft, submarine, carrier, etc. The second and third letters provide more specific information about invisible light, communications, direction finding, etc. A number following the letters uniquely identifies the equipment model. Variations may include hardware configuration, plugins, or cryptographic designations.

1. Designation System Codes
AN = Army/Navy
Example AN/ = Army/Navy Designation System
Installation Information Function FIRST LETTER SECOND LETTER THIRD LETTER
A:
B:
C:
D:
E:
F:
G:
H:
I:
J:
K:
L:
M:
N:
O:
P:
Q:
R:
S:
T:
U:
V:
W:
X:
Y:
Z:
Manned Aircraft Invisible Light, Heat Radiation Auxiliary Assembly
Submarine Comsec - NSA Reserved Bombing
NSA Reserved Carrier - Electronic or Signal Communications
Pilotless UAV/D rone Ionizing Radiation Direction Finding/Recon
Lazer Ejection and/or Release
Fiber Optics
Ground Fixed
General Ground Use Telegraph or Teletype
Fire Control or Searchlight Directing
Recording and/or Reproducing
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Interphone and Public Address
Electromechanical
Amphibious Telemetering Computing
Countermeasures
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Ground Mobile Meteorological Maintenance
Manned Aircraft
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Human Portable
Radar
Sonar and Underwater Sound
Radio
Special or Combination
Special or Combination
Receiving or Passive Detecting
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Active Surface Ship Detecting, Search
Ground Transportable
General Utility - Multi Use
Vehicle
Telephone Transmitting
Visual, Visible Light
Water Miscellaneous Weapons Remote Control
Television or Fax Identification or Recognition
Computing - Data Processing
Targeting Tracking, Fire Control
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NSA Reserved Communications-NSA Reserved Secure-NSA Reserved
The numbers following the three letters and dash (-)
uniquely identifies the equipment. Variations of same
equipment and more may follow the numbers.
(V)# = Hardware Configuration
P = Plugin or Component
C = Crytographic T = Training
DUOTECHSERVICES.COM
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Ref: en.Citezendium
AN/APG-66
A = Manned Aircraft P = Radar G = Fire Control 66 = Model