DP trial leads to partial blackout
- DP Event
- Published on 29 November 2016
- Generated on 18 September 2026
- DPE 04/16
- 1 minute read
Undesired event
The 230v supply breaker was open and the two uninterruptible power supply (UPS) batteries completely discharged.
Comments
It was discovered that the 230v supply breaker was open and the two uninterruptible power supply (UPS) batteries completely discharged.
Warning alarms generated by the DP system regarding the condition of UPS 2 were overlooked. An additional checklist item was added to the field arrival trials to check UPS 1, 2 and 3 are clear of alarms and operating as normal.
Vessel maintained position throughout.
Considerations
- The lessons to be learnt from the above are obvious and barriers preventing such errors are essential.
- Alarms presented to operators must be acknowledged and acted on.
Latest DP incidents
-
Know your equipment, or at least where to find the answers
During an update in the Follow Target Mode, the crew noticed an anomaly with joystick control.
DPE 02/26
1 September 2026
Observation
-
New equipment, unexpected consequences
During the operation, a loss of DGNSS correction signals was experienced across multiple vessel DGNSS units.
DPE 02/26
1 September 2026
Incident
-
A chain of small failures leads to a major consequence
While conducting cargo operations on DP a vessel experienced a partial blackout caused by an unexpected shutdown of generator 3
DPE 02/26
1 September 2026
Incident
-
Holding position, losing references
While approaching a turret-moored, weather-vaning offshore installation (FPSO), in preparation for cargo operations, a DP equipment class 2 vessel experienced significant rolling of up to 15–20° due to a long-period swell close to the vessel’s natural roll period, resulting in a resonance effect
DPE 02/26
1 September 2026
Observation
-
DP drill scenario – Loss of seawater cooling pump redundancy
Exercise scenario – Loss of seawater cooling pump redundancy
DPE 02/26
1 September 2026
Drill Scenario
The case studies and observations above have been compiled from information received by IMCA. All vessel, client, and operational data has been removed from the narrative to ensure anonymity. Case studies are not intended as guidance on the safe conduct of operations, but rather to assist vessel managers, DP operators, and technical crew.
IMCA makes every effort to ensure both the accuracy and reliability of the information, but it is not liable for any guidance and/or recommendation and/or statement herein contained.
Any queries should be directed to DP team at IMCA. Share your DP incidents with IMCA online. Sign-up to receive DP event bulletins straight to your email.