Signalman 1 & C - Historic Naval Ships Association

CHAPTER 6INTERNATIONAL SIGNALINGIn wartime and peacetime, communications arenecessary between U.S. Navy ships and merchantmensailing throughout the world. Vessels of many nationscome in contact with one another, exchangingmessages of varying degrees of importance.This chapter discusses some of the facets ofinternational signaling, such as the manner of callingand answering, message construction, and use ofprocedure signals and signs. International signalingprocedures are in many respects similar to those usedby allied naval units. Every signalman must be aware,however, there are significant differences.When communicating with a merchantman, youmust remember to use international procedure.Merchantmen do not have access to all of ourpublications, nor are they required to know Navyprocedure. So take a little extra time and learn how tocommunicate with merchantmen.Much of the information you will need to know tocommunicate with merchantmen is contained in theInternational Code of Signals, Pub 102.SIGNALING INSTRUCTIONSLEARNING OBJECTIVES: Explain theprocedure for signaling from the InternationalCode of Signals, using explanation and generalremarks, definitions, and general instructions.Explain the procedures for signaling usingflags, flashing lights, sounds, radiotelephones,and hand flags or arms to communicate withmerchantmen.EXPLANATION ANDGENERAL REMARKSThe purpose of the International Code of Signalsis to provide ways and means of communication insituations related essentially to safety of navigationand persons, especially when language difficultiesarise. In the preparation of the Code, account wastaken of the fact that wide application ofradiotelephony and radiotelegraphy can providesimple and effective means of communication in plainlanguage whenever language difficulties do not exist.The Code consists of four chapters, an appendix, andtwo indexes:1.2.3.4.5.6.Chapter l—Signaling InstructionsChapter 2—General Signal CodeChapter 3—Medical Signal CodeChapter 4—Distress and Lifesaving Signals andRadiotelephone ProceduresAppendix—U.S/Russia Supplementary Signalsfor Naval VesselsIndexes—Signaling Instructions and GeneralSignal Code, and Medical Signal CodeDEFINITIONSWhen a man-of-war and a merchant ship desire tocommunicate, it is extremely important for thoseinvolved in the use of the Code to follow theprescribed terminology. The following terms have themeanings indicated:1. Sound signaling: Any method passing Morsesignals by means of siren, whistle, foghorn, bell, orother sound apparatus.2. Identity Signal: The group of letters and figuresassigned to each station by its administration.3. Station: A ship, aircraft, survival craft, or anyplace at which communications can be effected by anymeans.4. Station of origin: Station where the originatorsubmits a signal for transmission, regardless of themethod of communication used.5. Station of destination: Station in which thesignal is finally received by the addressee.6. Receiving station: The station by which a signalis actually being read.7. At the dip: A hoist or signal is said to be at thedip when it is about half of the full extent of the halyards.8. Group: Denotes more than one continuous letterand/or numeral that together compose a signal.6-1