Bad connection causes loss of DGNSS
- DP Event
- Published on 2 June 2017
- Generated on 27 October 2026
- DPE 02/17
- 1 minute read
Observation
There was water ingress at the L-Band connector to the antenna on the vessel's mast.
Comments
After all the checking, it was found that there was water ingress at the L-Band connector to the antenna on the mast. This was dried and cleaned. The connectors were properly sealed with self-bonding electrical tape and cable ties.
Considerations
- This observation reinforces the need for good practice conducting field entry/arrival DP checks making sure all DP systems are operational and healthy.
- It is unclear why the laser-based reference system was not in use but it is assumed the system was not immediately available due to distance or shadowing.
- Several recent reports indicate the use of only two enabled position reference systems (PRS), these are often both DGNSS. It cannot be stressed enough that a mixture of PRS should be used.
- Regular checks of connections which are exposed to the environment need to be carried out and included in planned maintenance systems.
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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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