Signalmen must be alert to respond to a flashing light or semaphore call without delay. At night, Signalmen must use extreme care to avoid illuminating the ship's bridges and aircraft. Such illumination reduces the night visual acuity of pilots and conning officers. Whenever practicable during carrier night-flight operations, infrared (IR) systems should be used instead of visible flashing light. LOCATING SHIPS IN FORMATION Before you can send a visual message to another ship, you first must know where that ship is located. A Signalman with a message in hand, not knowing the location of the addressee, would be in the same plight as a postman trying to deliver a letter that has no address. When operating with only one other ship, there is no great difficulty. Operating with a large force, however, does present a problem, and the problem becomes even more complex at night. Infrared communications during darken ship operations would be impossible without some method of keeping track of ships in the formation or locating them. Signalmen on the signal bridge maintain an up-to-date plot of all ships in company. One of the best systems for plotting ships is a formation plot drawn on a maneuvering board. The maneuvering board itself is a compass rose with range circles, containing speed, distance, and time scales. Your only interest in the board at this time is how to use it in plotting and locating other ships in formation. You will learn more about how to solve maneuvering board problems in Signalman, volume II. The different formations and their component stations are contained in Allied Maritime Tactical Instructions and Procedures, ATP 1, volume I. Using the formation in figure 8-1, imagine yourself as the Signalman on USS Farragut (DDG-37) with a message for USS Dewey (DDG-45). By checking the formation plot, you find that Dewey is in station No. 4 and that your own station is No. 8. Place a set of parallel rulers so they intersect your station and that of Dewey (single dashed line in fig. 8-1). Move the parallel rulers to the center of the plot (along the paths of the double lines). Where the parallel rulers cross the outside ring of the maneuvering board is the true bearing (330°T) of Dewey from your ship. The formation course is 050°T, 8-3 so the relative bearing of Dewey is 280° (true bearing less course), or just forward of your port beam. Now that you have located the addressee, you can deliver your message. SPOTTERS When operating in company, spotters are stationed on the signal bridge from dawn to dark to watch for signals from the OTC and other ships in company. They must be alert at all times. Spotters must be able to read flaghoist accurately. They call out each flag in the signal in a loud, distinct voice so that personnel on the flag bags and personnel relaying the signal to those responsible for determining the meaning of the signal can hear the signal clearly. If the originating ship maneuvers in such a manner that its signals cannot be distinguished, the spotter should immediately inform another member of the signal force to spot the ship from another position on the signal bridge. Where there are obstructions such as smoke, haze, fouled flags, or sun glare, the spotter should be given assistance. Regardless of the effort involved or the means necessary, the signal must be obtained with minimum delay. Chapter 5, covered flaghoist terminology used by the spotter. RECORDERS/MESSENGER An important duty of Signalmen and strikers is to record signals and messages being read by another Signalman. The date, time of transmission or receipt, reference numbers, date-time group, means of transmission, transmitting and receiving ships, and relaying ships or stations all must be carefully recorded. Messages are initialed by the operator and supervisor at the time of receipt or transmission. Normally, originals of nontactical messages, after being initialed, the signalbridge messenger, usually the same person that recorded the message, routes it to the OOD or captain, after which a copy is sent to the communications center for write-up and internal distribution. The method for handling tactical signals was discussed in chapter 5. Personnel Qualification Standard for Visual Communications, NAVEDTRA 43354A, section 301 must be completed to perform the duties of signalbridge recorder/messenger.