Damage control communications are vital to a ships survival during emergency conditions. Each repair party is required to keep DCC informed of the damage status within its area. At the same time, each repair party needs to monitor the reports from all the other repair parties. By monitoring these reports, each repair part y will be able to assume the duties of DCC if DCC becomes a battle casualty. If adequate DC communications are not maintained, the entire DC organization could break down rapidly and fail to perform its primary functions.

The following communication methods are used for DC communications:

4. Ships loud speaker or general announcing system

Figure 2-7.-A pegboard. 2-14

As a Damage Controlman you must be familiar with the communication systems used by the damage control organization on your own ship. Detailed information on communications can be found in the Ship Information Book for your ship. Various communication methods will be discussed in this chapter. However, the information given here must be regarded as general in nature; it does not apply to all types of ships.

BATTLE TELEPHONE CIRCUITS

The battle telephone circuits are soundpowered circuits. Therefore, they require no outside source of electrical power. The transmitter of a sound-powered telephone transforms sound waves into electrical energy. The receiver transforms this electrical energy back into corresponding sound waves.

Each sound-powered circuit provides communication between certain designated stations. Each circuit consists of telephone jack outlets connected by a line or lines. The connection may be direct or it may be through intermediate equipment such as switchboards, switch boxes, or transfer switches. Some of the vital circuits can be cross-connected with other circuits.

The sound-powered battle telephone system is made up of five types of circuits: primary, auxiliary, supplementary, emergency, and miscellaneous. Sound-powered telephones are also classified according to the type of control, as follows:

1. Switchboard-type circuits are controlled from a switchboard at a central location.

2. Switch box-type circuits are controlled from a switch box located at the station exercising operational control over the circuit.

3. String-type circuits have all stations connected in parallel, with no switching provided.

The primary, auxiliary, and supplementary circuits of the ship's battle telephone system are permanently installed. These circuits have outlets located at numerous critical locations throughout the ship. The emergency circuits are string-type circuits which have permanently installed jack boxes.

Primary Circuits

The number of primary circuits used within the sound-powered battle telephone system varies among ships. The choice of circuits is largely determined by the size and type of the ship. The primary circuits discussed here are normally found on large combatant ships. Not all of these circuits are found on smaller ships. The circuits discussed here include only those that are of particular importance in damage control communications.

CIRCUIT 2JZ is the damage and stability control circuit. This circuit provides vital communication between damage control central, secondary damage control central, engine rooms, repair stations, antiaircraft stations, weapons control center, and draft gauge. Each repair party circuit has an outlet in DCC. This maybe through a selector switch, through individual jack boxes, or through a combination of both. The latter arrangement is preferred because it permits the manning of each circuit by individual phone talkers. When the combination of the selector switch and individual jack boxes is used, the 2JZ circuit is preferably used as an outgoing circuit. Information and orders from DCC are passed to the repair parties. Each individual repair party circuit thus becomes an incoming circuit into DCC. Therefore, the DCA either receives information or orders action to be taken on any message carried over any individual repair party circuit.

When individual repair party circuits come into DCC only through a selector switch, or when individual phone talkers are not available, the system must be reversed so that the 2JZ circuit becomes the incoming channel for information. The individual repair party circuits receive only such information or orders from DCC that are intended specifically for them. This may prevent repair party officers from receiving all of the information being sent to other repair parties.

In smaller ships, only a single circuit may be available. In this situation, both incoming and outgoing messages must be handled over it. It is also possible that this circuit will not be primarily or entirely a damage control circuit. Therefore, it is imperative that control of this circuit be established by the major controlling station. This will ensure an orderly flow of communication. The circuit must never be allowed to get out of control as a result of cross-talk when more than one station assumes priority. The controlling station must be able to clear the circuit immediately and establish priorities for messages whenever the need arises.

CIRCUIT 3JZ provides communication between Repair 1 and DCC, secondary DCC, topside battle dressing station and each unit patrol station associated with Repair 1.

CIRCUIT 4JZ provides communication between Repair 2 and DCC, secondary DCC forward battle dressing station, each unit patrol station forward of engineering compartments, fire pump controllers (except aircraft carriers), and fog-foam injection stations (aircraft carriers only).

CIRCUIT 5JZ provides communication between Repair 3 and DCC, secondary DCC, after battle dressing station, each unit patrol station associated with Repair 3, remote-operated valve control stations aft of the engineering compartments, fire pump controllers (except aircraft carriers), and fog-foam injection stations (aircraft carriers only).

CIRCUIT 6JZ provides communication between Repair 4 and DCC, secondary DCC, amidship battle dressing station, each unit patrol station associated with Repair 4, remote-operated valve control stations amidship, fire pump controllers (except on aircraft carriers), and fog-foam injection stations (aircraft carriers only).

CIRCUIT 7JZ provides communication between Repair 5 and DCC, secondary DCC, engine rooms, firerooms, and each unit patrol station associated with Repair 5.

CIRCUIT 8JZ provides communication between Repair 8 and DCC, secondary DCC, primary and secondary fly control, auxiliary fly control, and each unit patrol station associated with Repair 8.

CIRCUIT 9JZ provides communication between forward Repair 6-F and DCC, secondary DCC, gunnery control station, remote sprinkling control station and each manual sprinkling valve control unit.

CIRCUIT 10JZ provides communication between after Repair 6-F and DCC, secondary DCC, gunnery control station, remote sprinkling control stations and each manual sprinkling valve control unit.

CIRCUIT 12JZ provides communication for the operating orders for fire pump control and the maintenance of firemain pressure in the event of damage. Communication facilities are provided between such stations as DCC, secondary DCC, each conflagration station and hangar deck lighting control station, and the controllers for each fire pump.

CIRCUIT JA is the captain's battle circuit. This circuit provides communication between such stations as the open bridge, pilot house, captain plot, secondary corm, combat information center (CIC), gunnery control stations, antiaircraft stations, weapons control center, fire control plotting rooms, DCC, secondary DCC, and flag plotting station.

Auxiliary Circuits

Most ships have auxiliary circuits, which duplicate primary circuits. The wiring for the auxiliary circuits is installed as far away as possible from the wiring for the primary circuits. This helps to minimize the danger of both the primary and the auxiliary circuits being placed out of commission at the same time. The auxiliary sound-powered circuits are identified by an X in front of the circuit designator. Examples of auxiliary circuits are X2JZ and X1JV.