Unfamiliarity with DP system leads to an undesired event
- DP Event
- Published on 13 June 2019
- Generated on 6 November 2026
- DPE 02/19
- 2 minute read
Undesired event
Vessel specific familiarisation programmes and operation manuals should make allowances for crew members not being familiar with systems.
Comments
Both DPOs had several years’ experience but with a different DP control system where it is common to stop the vessel during a move by reducing speed to 0.0kts.
However, on the system fitted to this vessel a retardation factor is used so speed is reduced automatically when the stop request is made.
Setting a speed at 0.0kt led to an unstable situation. The master instructed DPOs to keep a minimum speed on DP of 0.1kts and not set speed to 0.0kts.
Considerations
- Vessel specific familiarisation programmes and operation manuals should capture and make allowance for crew members not being familiar with systems. Each system/vessel has peculiarities which must be taught and learned by the crew onboard.
- The DP system manufacturer should be involved as it should not be possible for the operator to apply a valid setting which then causes an unstable DP system.
- It is recognised practice to slow down during a move, but it is not considered good practice to use zero speed.
- The use of the present position would maintain the vessel in the wanted position.
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