Vessel Makes Contact with Installation
From the Marine Safety Forum
A vessel was heading towards an installation in preparation for setting up cargo operations. As the officer of the watch closed the platform, he moved the controls in order to swing the vessel but it had no effect. He turned the controls further and increased power, still with no effect. Finally he turned the controls 180° to give reverse thrust and further increased power, but this had the unwanted effect of increasing the vessel’s speed and, subsequently, it made contact with the platform.
The vessel is fitted with 360° azimuth propulsion units and not a conventional propeller arrangement. In order to steer using this system, the whole unit is moved and pointed to create thrust in the required direction.
Each unit can be operated independently giving great manoeuvrability and flexibility. Direction of thrust astern or forward is solely dependant on the direction the azimuth units are pointing in. In addition, on this particular vessel the auto pilot has priority over the controls so, when engaged, rotating the manual controls has no effect on the direction of propulsion at all.
The officer of the watch had forgotten to disengage the auto pilot before entering the 500m zone resulting in the auto pilot continuing to control the direction of the vessel despite the officer of the watch’s attempts to manoeuvre, and in increasing power he just exacerbated the problem.
The investigation identified several failings that lead up to this incident:
• The officer on watch entered the 500m zone of the platform without completing a pre-
500m zone checklist, as required by company and client procedures as detailed in the
• He did not call an additional person up to the bridge before entering the 500m zone.
• He left the vessel on auto pilot when he entered the 500m zone.
Several actions resulted from the recommendations of the accident report:
• Formal company written checklist to be drawn up and made mandatory for all 500m
entry operations across the fleet. Checklist to be retained on board in dedicated folder
and to be checked during audit and client / management visits.
• Clarification of document control process for ensuring client information is placed on
• Fit audible and visible alarms that cut in if attempts are made to use the controls whilst
the autopilot is engaged.