Leak in fuel supply line causes engine to shut down – DP undesired event

Comments from the report:

The vessel was employed within the renewable energy sector, no details were given of the drilling activities.

A fuel leak developed in a corroded supply pipe to the port main engine.  This caused air to be drawn into the system and the engine to shut down.  Redundancy worked as designed.  The split fuel system ensured that only the port side of the engine room was affected and operations were suspended due to loss of redundancy.

Considerations of the IMCA Marine DP Committee from the above event:

• It was noted that 3 DGNSS were selected to DP; clearly this is not in accordance with DP equipment class 2 that requires position reference systems to have at least 2 different principles of operation.
• The vessel was operating closed bus and while the failure did not exceed the vessel’s designed worst case, a different fault on the electrical system may have resulted in a more significant DP system failure.
• Water depth of 45m only provides a small envelope of operation.
• Actions taken in response to the failure appear to be appropriate and in line with good practice.
• The planned maintenance system (PMS) for critical piping systems should be reviewed.  For an F.O. supply line to fail due to corrosion should warrant complete inspection of the rest of the system, and a review of past inspections/maintenance so that similar faults are not missed in the future.