RADIOTELEPHONE CALL SIGNS Call signs used in radiotelephone are commonly known as voice call signs. They consist of spoken words, which can be transmitted and understood more rapidly  and  more  effectively  than  actual  names  of  ships and  afloat  commands,  or  phonetic  equivalents  of international   radio   call   signs.   Under   certain circumstances,  however,  the  phonetically  spelled international  call  sign  is  used  in  R/T  for  station identification. At other times, a ship’s name serves as the call sign. R/T  call  signs  may  be  assigned  by  an  operation order  (OPORD),  a  tactical  communication  plan (COMMPLAN),  or  permanently  by  commonly  held communications publications. R/T call signs may be either  permanent  or  temporary,  and  they  may  be internationally usable or locally issued. In any event, call signs are used to identify the station and to establish communications. A station’s call sign can be any of the following: The name of the ship or aircraft tail number; A voice call sign listed in Joint Voice Call Sign Book, JANAP 119; An allied voice call sign listed in  Tactical  Call Sign Book (U), ACP 110; and/or A call sign for ships listed in Call Sign Book for Ships, ACP  113. Voice  Communications,  NTP 5, lists publications that contain encrypted and daily changing call signs. A ship must use its call sign when first establishing a net or when reporting into a previously established net.  After this initial contact, an abbreviated form of communications may be used. If call sign encryption is in effect and a ship or unit name appears in the text, the name should be replaced by the encrypted call sign or address group of the ship or unit. When used in this manner, the call sign or address group may be preceded by the proword CALL SIGN or ADDRESS GROUP, as applicable. ACP 113 CALL SIGNS ACP 113 lists the international call signs and hull numbers for ships under military control. The call signs in this publication are unclassified. International call signs are used for all nonmilitary communications and military  communications  using  unencrypted  call  signs. 2-14 JANAP 119 VOICE CALL SIGNS Voice call signs contained in JANAP 119 are pronounceable words. They are for tactical use and are designed to facilitate speed on tactical radio circuits. Secure voice call signs can be achieved only by a conscientiously applied system for changing call signs on a frequent and periodic basis. CALL SIGNS ON LOCAL HARBOR CIRCUITS JANAP 119 does not assign voice call signs to administrative  shore  activities.    Consequently,  a  ship cannot use a tactical call on administrative ship-shore circuits. When operating on ship-shore R/T circuits, a ship may use its international call sign. Operators must speak the call sign phonetically. For example, you would speak the international call sign NOKB as “November   Oscar   Kilo   Bravo.”   The   procedure described in the next paragraph may also be used. In U.S. ports and U.S.-controlled ports overseas, the name of the ship serves as the voice call sign.  As a rule, the USS prefix, hull designation and number, or the first name or initials of the ship need not be included in the voice call unless essential for clarity. This procedure   also   applies   to   shore   activities   on administrative   nets.   Each   activity   may   use   its administrative title in an abbreviated form, consistent with clarity. For example, Mobile Technical Unit 2 may have a voice call of MOTU on an administrative circuit. Port authorities that control local harbor voice circuits are identified by the word “CONTROL.” For example, let’s say that the Key is entering port in New London, Conn. Key’s initial call to New London Control to check into the local harbor net would be: “Control, THIS IS Key, OVER.” If  Key were to call Fuel Control, its call would be: “Fuel Control, THIS IS Key, OVER.” You  must  remember  that  the  simplified  type  of  call is authorized only in U.S. ports or U. S.-controlled ports. If a ship is in a port not under U.S. control, it must conform   to   the   international   practice   of   using phoneticized international call signs on R/T circuits. RADIOTELEPHONE  CIRCUITS Voice  communications  requirements  are  grouped into  two  basic  categories:  operational  or  tactical,  and administrative.