Swinging load after loss of position
- Safety Flash
- Published on 18 June 2024
- Generated on 17 September 2025
- IMCA SF 12/24
- 2 minute read
PSV suffered loss of position and an uncontrolled swinging load.
What happened?
During backloading of an empty refrigerated container to a Pipe Supply Vessel (PSV), adverse weather conditions, combined with technical issues and the effect of high thrust wash, resulted in a loss of position of the PSV and an uncontrolled swinging load. There was no damage to equipment and no-one was harmed.
This event will also appear as an IMCA DP Incident report.
Container on deck
Container swinging
What went wrong?
- Sudden gusts of wind of around 40 knots created high external forces, which resulted in an increased thruster wash towards the PSV, which caused the PSV to lose position.
- The PSV’s azimuth thruster lost its running DP signal, contributing to the loss of position.
- The PSV was operating outside its Activity Specific Operation Guidelines (ASOG).
- The operational limits of PSVs operating alongside were not considered in the Activity Specific Operation Guidelines (ASOG).
- No-one stopped the job: the operation wasn’t stopped despite alarms indicating the PSV was outside defined operational limits.
Lessons learned
- Review any (project specific) ASOG to include vessel to vessel operations and the effect that thruster wash can have on vessels alongside.
- Review and update procedures for the lifting of cargo to/from PSVs to reflect the potential for loss of position.
- Ensure personnel responsible for DP operations review and consider the requirements of the ASOGs and document their review process.
- Planning, risk assessing and adhering to operational guidelines and limits is crucial to ensuring safe cargo transfer operations.
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