LEARNING OBJECTIVE Discuss the common pyrotechnic devices currently in use on modem Navy surface ships.

Pyrotechnic is the Greek word for fireworks. The Navy uses fireworks not for celebration, but for illumination, marking, and signaling. An example is the illuminating projectile, or star shell, used to illuminate targets for gunfire. A star shell actually is a pyrotechnic device, although it is encased in a projectile body of standard external shape and is fired from a standard rifled gun.

In the following sections we will discuss the common pyrotechnic devices currently in use on modern Navy surface ships. For further information on these and other pyrotechnic devices used by the Navy, refer to Pyrotechnic, Screening, Marking, and

Countermeasure Devices, NAVSEA SW050-AB-MMA-010. All the pyrotechnics we study here are intended for signaling and marking. In the following sections, we will discuss common

1. marine location markers,

2. marine illumination signals and the pyrotechnic pistols and projectiles used in firing them, and

3. distress and hand signals.

Also, at the end of this section on pyrotechnics, we will provide some basic information on the proper handling and stowage of these devices.

MARINE LOCATION MARKERS

Marine location markers are used as night or day long-burning referenee markings on the surface of the ocean. They are dropped over the side from surface ships for man-overboard marking, navigation drills, and other similar operations. These markers may also be dropped from aircraft for search and rescue operations. The two marine location markers currently in use are the Mk 58 and the Mk 6.

Mk 58 Marine Location Marker

The Mk 58 marine location marker is the primary marine location marker found aboard surface vessels. It is approximately 21 1/2 inches long and weighs about 123/4 pounds. It contains a battery squib, some starter mix, two pyrotechnic candles, and a transfer fuse between the two candles. Before launching, the tear tape over the water port must be removed so that seawater can enter to activate the battery. Battery current energizes the electric squib, which ignites the starter mix, which, in turn, lights the pyrotechnic candle. When the first candle has burned out (in 20 to 30 minutes), the second candle is started by the transfer fuze for a total burning time of approximately 40 to 60 minutes. The Mk 58 currently is available in two versions: the Mod O and the Mod 1. The Mod O is a hermetically sealed can that is opened with a twist key. Figure 1-4 shows this

Figure 1-4.-The Mk 58 Mod 0 marine location marker.

marker. The Mod 1 (fig. 1-5) is capped with a replaceable polyethylene cover.