RADIOTELEGRAPH Radiotelegraph messages are to be sent over the radiotelephone net. The entire radiotelegraph version of the message is to be passed as the text of the radiotelephone message. SHIP/SHORE TRANSMISSION Ship/shore radiotelephone transmissions are to be made according to the International Telecommunications Union Regulations, article 33. MASTER'S COMMUNICATIONS RESPONSIBILITIES The master, like the allied commanding officer, has overall responsibility for all communications maintained by his/her ship. He/she therefore has the authority and the obligation to order or prohibit any transmission being made from his/her ship. He/she decides whether or not to break radio silence and to permit or refuse participation in distress traffic. On arrival in an allied port, the master reports immediately to the NCSO all defects in communica- tions equipment that cannot be repaired on board before the ship sails again. The master is also responsible for ensuring that all communications personnel are knowledgeable of the instructions necessary for the performance of their communication duties, and to ensure that any orders received are passed to them. The master will be furnished with the necessary publications by the NCSO. He/she is responsible for them and must ensure all instructions for the maintenance and security of the pubs are observed and that amendments are inserted. COMMUNICATIONS PLAN The communications plan is an important part of the Sailing Order Folder. Basic radio com- munications organization and procedures for all ships, sailing independently or in convoy, upon which the radio communications plan will be based, are found in the communications supplement of ATP 2, volume II. SIGNALS USED IN CONVOY Ships in convoy are to use the signals provided in ATP 2, volume II, the International Code of Signals or the International Q code. Subject to the transmission policy in force, these signals may be transmitted by voice radio or visually. The majority of the signals required in convoy operations can be found in ATP 2, volume II, chapters 11, 12, and 12A. When warship Signalmen make use of those signals, they will be preceded with the 4^TH substitute. Vocabulary The vocabulary, chapter 12, consists of three- letter signal groups, each starting with the letter X. Groups are arranged in alphabetical sequence for ease of reference. This chapter is used for encoding. Chapter 12A is used for decoding. Maneuvering Signals Chapter 11 contains maneuvering signals, maneuvering instructions, supplementary signals, and single-letter signals. Single-Letter Signals Single-letter signals in ATP 2, volume II, are contained in table 11-VI. Flags T and W will precede the port or starboard pennant and three numerals to indicate the direction of the alteration of course. Single-numeral pennant signals are also found in chapter 11, table 11-VII. NOTE The Code pennant is to precede signals taken from INTERCO. It should be noted that single-letter signals from the INTERCO have different meanings than signals from ATP 2, volume II. CLASSIFIED RECOGNITION SIGNALS Extracts of recognition material will be issued to each ship by the NCSO. The current period signal must be given to the officer of the watch. Ships must identify themselves promptly when challenged by allied warships, aircraft, examination vessels, or the signal station. TIME USED IN SIGNALS GMT is to be used in all communication. Clocks are to be set and so labeled. MAN OVERBOARD A ship that loses a person overboard must immediately make the signal “MAN OVERBOARD” 7-9