Loss of redundant group (for example, Port SW/BD)
- DP Event
- Published on 18 December 2025
- Generated on 2 November 2026
- DPE 03/25
- 4 minute read
Drill Scenario
DP emergency drill scenarios are included to assist DP vessel management and DPOs / Engineers and ETOs to conduct DP drills onboard. The intent is that the template can be used on any DP vessel, so specific details regarding the technical outcome are not included. The benefit of using this template is to monitor and learn from the human reactions of key DP personnel. It is also important that the crew are familiar with various DP system set-ups, including their failure modes.
Refer to IMCA M117 Code of practice for the training & experience of key DP personnel, Appendix G.
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EXERCISE SCENARIO LOSS OF REDUNDANT GROUP (e.g. PORT SW/BD) |
Objective:To observe the reaction of the crew and verify vessel’s remaining capability following loss of any one redundant group. |
Method:With the vessel in full auto DP control; power plant configured according to the vessel’s DP FMEA and DP Operations Manual (and respective decision support tool); all other vessel equipment and systems set up in accordance with applicable DP checklists: Vessel in a safe location. Simulated location and activities agreed and communicated to all participants. Simulate the failure by tripping online generators on the applicable redundant group. Observe reaction of DPO crew, DP technical personnel, the equipment, DP system behaviour and potential vessel position/heading excursions. |
Prior to Executing, Discuss the Expected Results:
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Observations During Exercise:
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Actual Results Witnessed:EXAMPLE: DP system loses redundant group thrusters. System allocates thrust so there is no loss of heading or surge control, the vessel maintains position with remaining thrusters. If vessel is set up with due regard to applicable ASOG parameters, thruster and generator loads are within acceptable limits. |
Discussion Points (post-Exercise):
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Conclusion:Based on the results of the exercise and related discussions before and after, any suggestions for follow up including any corrective actions deemed appropriate should be accurately detailed and managed to close out. |
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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.
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