Inadequate communication and planning causes fouled thruster
- DP Event
- Published on 29 March 2017
- Generated on 16 September 2026
- DPE 01/17
- 1 minute read
Undesired event
They did not realise they were isolating the opposite thruster and consequently the thruster closest to the lay chute was still running.
Comments
During the over boarding of the end termination through the starboard aft chute, the cable laying shift supervisor asked the bridge to isolate thruster No.5 (port quarter) instead of thruster No.6 (starboard quarter).
They did not realise they were isolating the opposite thruster and consequently the thruster closest to the lay chute was still running. Moreover, they asked the bridge to move backwards and in the same direction where the end termination was being laid down. This movement contributed to the end termination deployment rope fouling thruster No.6.
Considerations
- There was either a lack of operational planning or it was inadequate.
- The event highlights the need for accurate and verified communication between key control centres.
- With three satellite derived position systems on line and the acoustic system on standby the vessel was not complying with the requirements of IMO Circular 645.
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.