Valve problem caused loss of steering, grounding

The Portugal/Madeira flagged bulk carrier ran aground on the river Weser while sailing northbound. At the time, both steering gears were running and the helmsman was steering using the hand wheel.

At around 2155, the helmsman intended to return the rudder to midships from an angle of about 15° starboard. Initially nothing happened, despite a correct hand steering wheel position. Instead, the rudder remained at 15° starboard. After a few seconds, the steering control system automatically switched from hand wheel to tiller, accompanied by a clearly audible and visible alarm.

The ship’s command directly switched the controls back to manual steering. At the same time, the rudder angle changed to hard starboard (45°) and again remained there, still without reacting to rudder angle inputs from the hand wheel. The vessel’s rate of turn, already high at that point, accelerated even further.

Despite an immediately initiated full-astern manoeuvre, the Rubina’s bow ran aground within moments. Fortuitously, this happened in a relatively innocuous position on the Weser.

After salvage operations the following day, the Rubina was towed to a waiting pier in Brake and was able to continue its voyage two days later.

The cause of the non-responsive rudder was found to be a pilot valve of steering gear pump no. 2 which had stuck in an open position for a while, perhaps due to contamination. It was not possible to establish conclusively what had caused the pilot valve to stick.

The report is available here.