Alerts iconCase study – Switching from auto DP to IJS (independent joy stick) mode caused loss of control

Case narrative A vessel collided with the working platform on a wind turbine transition piece. The incident occurred during worsening weather conditions. The vessel was on auto DP, when it was decided to pull off. Whilst moving away from the turbine, the DP operator switched from auto DP to independent joy stick (IJS) mode. The … Continue reading “Case study – Switching from auto DP to IJS (independent joy stick) mode caused loss of control”

Alerts iconLeak in fuel supply line causes engine to shut down – DP undesired event

Comments from the report: The vessel was employed within the renewable energy sector, no details were given of the drilling activities. A fuel leak developed in a corroded supply pipe to the port main engine.  This caused air to be drawn into the system and the engine to shut down.  Redundancy worked as designed.  The … Continue reading “Leak in fuel supply line causes engine to shut down – DP undesired event”

Alerts iconRoutine maintenance leads to loss of thruster – DP undesired event

Comments from the report: During a routine weekly maintenance operation, a ships engineer took an oil sample from the starboard azimuth thruster sample point, which is a small valve located on the line to the pressure switch.  The location of the oil sample point on the line to the pressure switch creates a risk of … Continue reading “Routine maintenance leads to loss of thruster – DP undesired event”

Alerts iconElectrical fault causes loss of thruster – DP undesired event

Comments from the report: One of the three frequency converters on the port azimuth thruster was found to be burnt out.  Initial actions:  The thruster was isolated and faulty converter dismantled. Under the instructions from the manufacturer, the thruster was set up to work up to a maximum of 60% of the load. The activity … Continue reading “Electrical fault causes loss of thruster – DP undesired event”

Alerts iconA retrofitted capacitor caused a bow thruster frequency drive to overheat – DP observation

Comments from the report: A wrongly installed extra capacitor at the bow thruster frequency drive caused overheating of this equipment. The extra capacitor was installed by the electrical designer and supplier of this equipment. It was also removed following consultation with the original equipment supplier. Considerations of the IMCA Marine DP Committee from the above … Continue reading “A retrofitted capacitor caused a bow thruster frequency drive to overheat – DP observation”