3. The aircraft should be maneuvered into a favorable position so that the signaler can have an unobstructed view for as long a period as possible. 4. Accurate training of the light by the operator at all times is most important. Aircraft are called by the means of the prosign AA, the unknown station. Many aircraft cannot signal by flashing light, and an answer should not always be expected. If no answer is seen, the message is to be made through at least twice; repetitions are to be preceded by the prosign IMI. Receipt may be indicated by the aircraft rocking its wings. INFRARED COMMUNICATIONS Infrared communications are divided into two forms: directional and non-directional. Directional is the use of the standard searchlight fitted with the H hood. Non-directional is the use of the AN/SAT 2 system located on the yardarm. Infrared communication between separate ships is generally directional. A station having traffic for wide distribution will normally use non-directional procedures. The OTC may prescribe calling periods during which infrared traffic may be passed without a special signal to attract attention. For example, stations may be required to monitor for infrared signaling for 15 minutes beginning on the hour and half hour. Such instruction may be found in the operation orders, communications plan, or message traffic calling periods. At the beginning of the calling period, the OTC may transmit the appropriate operating signal and the call signs of the stations the traffic is for. Stations not included in the traffic list may secure their equipment unless they have traffic for the OTC or other units in company. To transmit infrared traffic outside calling periods or when calling periods have not been prescribed, the stations may be alerted by the code word NANCY HANKS on voice radio, the appropriate signal from ATP 1, volume II, or an operating signal. The point of train (POT) light is a steady infrared light used to assist the sender in locating the receiving station and in keeping his/her light properly trained. It is turned on to indicate that a station is communicating or is ready to communicate with infrared. It is turned off at all other times. In the event of non-directional procedure, the originator's POT lights will become its Nancy beacons, and the receiving stations will be able to train their receivers on the actual transmission. SEMAPHORE PROCEDURES LEARNING OBJECTIVES: Explain the procedure for calling, receipting, and requesting repetitions, interruptions, and relays by semaphore. Explain procedure for transmitting, rate of signaling, and the use of numerals. List special characters and semaphore abbreviations. Semaphore and flashing light can be used interchangeably. Semaphore is much faster and generally more secure than flashing light for short-distance transmission in clear daylight. Semaphore may be used to transmit messages to several addressees at once if the sender is in a suitable position. Because of its speed, it is better adapted for long messages than other visual methods. Semaphore can be used at night with the use of wands attached to flashlights. See appendix II for semaphore drills and procedures. Semaphore signaling procedures are similar to those used in flashing light. The general rules of visual responsibility apply; call signs are the same; and message parts are unchanged. Because of the different equipment used, some differences in procedure do exist. Care is to be exercised in selecting a good background from which to send a semaphore message. The better the background, the greater the signaling distance. The characters are to be formed in the same plane as the sender's shoulders, with staffs at their full extent, forefingers along the staff. When the sender is making the front sign, the flags should be crossed in front of the body. A distinct pause is to be made at each character according to the rate of signaling. When transmitting prosigns, operating signals, and abbreviations, make this pause of double duration. A double-duration pause is also recommended when sending coded messages. The front sign is made at the end of each word, group, prosign, or operating signal. Where double letters occur, the arms are to be dropped to the front 4-10