Tuesday, 11 March 2008

Emergency steering


So one of the seamanship evolutions we practised on Sunday morning was rigging and using the emergency steering. The Mersey's primary steering system is a hydraulic system which is robust, reliable but ultimately not infallible. A situation could be imagine where a hose splits or a pump fails and this would leave us with no steering. Now in a boat with two engines and two props this is not a major problem provided the steering fails when the rudders are in the centre. However, if they fail with 30 degrees of starboard rudder on it would be handy to be able to bring them back to midships.

For just this situation our steering system is designed so that the hydraulics can be disengaged allowing the rudders to move freely, we then carry two block and tackles which can be rigged onto a lever on the top of the rudder stock to enable the rudders to be moved (because the rudders are semi-balanced and small they are light enough to be moved even at full speed). The system only takes a few minutes to rig but needs two crewmembers to operate who must stand in pretty exposed positions on the rear deck.

Once rigged the system can be used to steer the vessel both at slow speed and high speed but the preferred option is generally to centre both rudders and then steer on the engines. Nevertheless, we often rig it and practise using it as it is good for developing teamwork and highlights the need for good, clear and timely communications.

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