In every tanker of 10,000 tons and above and every other ship of 70,000 tons and above the main steering gear shall have two or more identical power units complying with the requirements.
The main steering gear in every tanker of 10,000 tons and above shall, subject to the requirements and be so arranged that in the event of loss of steering capability due to a single failure in any part of one of the power actuating systems, other than seizure of a rudder actuator. Steering capability shall be regained in not more than 45 seconds after the loss of one power actuating system. The main steering gear shall comprise of.
- two independent and separate power actuating systems each capable of meeting the requirements of clause of meeting the requirements or
- at least two identical power actuating systems which shall be capable of meeting the requirements and when acting simultaneously in normal operation. Interconnection of the hydraulic power actuating system shall be provided, if necessary, for compliance with this requirement.
The loss of hydraulic fluid from one system shall be capable of being detected and the defective system automatically isolated so that the other actuating system or systems remain fully operational.
In any tanker of 10,000 tons and above but of less than 1,00,000 tones deadweight the main steering gear may be constructed in such a way that the single failure criterion required and is not applied to the rudder actuator or actuators;