Incident caused by software glitch

  • DP Event
  • Published on 14 May 2020
  • Generated on 22 September 2026
  • DPE 02/20
  • 1 minute read

Incident

This and similar incidents highlight the need for extensive testing of the software at all stages.

DPE 20.02 – DP incident caused by software glitch – Flowchart

Comments

The two metres move command was given in two one-metre steps to the DP system by the operator with a time lapse of a few seconds. This was investigated by the DP system vendor and was identified as a software glitch. Two consecutive incremental move commands before the window screen has time to refresh resets the DP system to a zero position automatically.

Instructions were put in place on-board this and similar vessels until the vendor remedies the software issue.

Considerations

  • This and similar incidents highlight the need for extensive testing of the software at all stages.
  • Many vendors continuously update their software with patches, revisions, etc. Vessel operators must ensure a robust management of change (MoC) procedure and suppliers should provide an appropriate rigorous testing program.
  • The DP operator(s) appear to have initially responded well to the incident and this is a credit to their training and competence.

The following IMCA Guidance would be relevant to this DP incident:

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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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