201914 Emergency slowdown override to the rescue

The vessel was inbound and the Master/Pilot exchange had just been completed. Suddenly, the auto emergency slowdown alarm for the main engine sounded and the RPMs began dropping. As the vessel was in the channel and there was traffic nearby the emergency slowdown override was activated and vessel was steered clear off all traffic. Then, in consultation with the pilot, the main engine telegraph was brought to Stop.

Crew already stationed at the bow were asked to lower the starboard anchor to water level for immediate use. The bridge was then informed that the automatic slowdown was caused by a crack in the main engine unit number two cylinder jacket cover, which had caused a loss of pressure in the cooling water system. The vessel was maintained in safe waters on the bank of the channel using the bow thruster and helm. Tugs were called for additional safety. The propulsion was restored by isolating the number two unit and the vessel brought to berth.

 

Lessons learned

• The investigation found that one of the four screws that secured the jacket had not been tightened correctly. This in turn had affectedthe gap between the cooling jacket and the screw head, causing the cooling jacket to crack.
• Irrespective of the actual cause of the failure, the bridge team reacted with aplomb by overriding the automatic slowdown for the time needed to place.