4.1.2 Steering gear control is to be provided:
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For the main steering gear, both on the navigating bridge and in the
steering gear compartment;
-
Where the main steering gear is arranged according to Pt 5, Ch 19, 2.1 General 2.1.4, by two independent control systems, both operable from the
navigating bridge. This does not require duplication of the steering wheel or
steering lever. Where the control system consists of a hydraulic telemotor, a
second independent system need not be fitted, except in a tanker, chemical tanker
or gas carrier of 10 000 gross tonnage and upwards;
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For the auxiliary steering gear, in the steering gear compartment and,
if power operated, it shall also be operable from the navigating bridge and is to
be independent of the control system for the main steering gear.
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Where the steering gear is so arranged that more than one control
system can be simultaneously operated, the risk of hydraulic locking caused by
single failure is to be considered.
4.1.3 Any main and auxiliary steering gear control system operable from the
navigating bridge is to comply with the following:
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Means are to be provided in the steering gear compartment for
disconnecting any control system operable from the navigating bridge from the
steering gear it serves;
-
The system is to be capable of being brought into operation from a
position on the navigating bridge.
4.1.4 The angular position of the rudder shall:
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If the main steering gear is power operated, be indicated on the
navigating bridge. The rudder angle indication is to be independent of the
steering gear control system;
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Be recognisable in the steering gear compartment.
4.1.5 Appropriate operating instructions with a block diagram showing the
changeover procedures for steering gear control systems and steering gear actuating
systems are to be permanently displayed in the wheelhouse and in the steering gear
compartment.
4.1.6 Arrangements for failure detection are to be provided with self-monitoring
capabilities. In the event of failure being detected, an audible and individual visual
alarm is to be initiated on the navigating bridge. See
Pt 5, Ch 19, 5.3 Monitoring and alarms. Where
system failure alarms for hydraulic lock,see
Table 19.5.1 Alarms, are provided, appropriate instructions are
to be placed on the navigating bridge to shut down the system at fault.
4.1.7 In the event of detecting a control system failure, which is likely to
cause uncontrolled rudder movements, see
Table 19.5.1 Alarms, the rudder is to retain its position at the
time of failure without manual intervention. Alternatively, consideration will be given
to the rudder moving to and retaining a position which is necessary for safe navigation
of the vessel or to return to the mid-ship position where technical justification is
submitted and is found to be satisfactory.