Figure 10-2.--Propeller order indicator-transmitter (circuit M).

No. 2 that a change in propeller revolutions has been

ordered.

Engine Order System

The engine order system (circuit MB) transmits

the required shaft direction orders (ahead/back) and

the ordered speed of each shaft from the pilothouse to

each propulsion gauge board.

An engine order indicator-transmitter for each

shaft (1MB for starboard shaft and 2MB for port shaft)

is mounted in the upper section of the ship's control

console. An operating handle is attached to each

indicator-transmitter, The lee helmsman operates the

handles whenever a change in shaft direction or speed

is ordered by the OOD. There is also a push button and

Figure 10-2.--Propeller order indicator-transmitter

a bell located on the console for each indicator-

(circuit M).

transmitter. The push buttons are used to alert the

appropriate engine room of a change in orders. The

bells alert the lee helmsman that the order has been

console, it is received and indicated on this propeller

acknowledged by the appropriate engine room.

order indicator-transmitter. The throttleman in engine

room No, 1 acknowledges the change by transmitting

Each engine room has one indicator-transmitter

the order back to the propeller order indicator-

(fig. 10-4) for its associated shaft. After receiving an

engine order, the throttleman acknowledges the order

transmitter in the ship's control console. In the event

by turning the knob and matching its transmitter to the

of an engineering casualty or specific test, the

received order. A push button is located on the

throttleman in the engine room can reverse the

procedure by requesting specific revolutions per

minute.

A propeller order indicator (fig. 10-3) is mounted

on the gauge board of engine room No. 2. This

indicator is used to inform the watch in engine room

Figure 10-3.--Propeller order indicator (circuit M).

Figure 10-4.--Indicator-transmitter (circuit MB).