Alerts iconMix of absolute and relative position reference systems – DP incident

Comments from the Report: It was considered that the movement towards the drill ship could have been caused by a combination of position reference system degradation and interaction from the Drill ship’s thrusters.  There was an advisory regarding service disruption from the DGNSS supplier in force at the time.  It was stated that the DPO … Continue reading “Mix of absolute and relative position reference systems – DP incident”

Alerts iconOperating outside DP equipment class 2 requirements – DP incident

Comments from the report: Although DP checklists were completed, the availability of the standby operator station was not confirmed.  The most probable cause for DPOS2 to freeze and not auto changeover was traced to a faulty IO controller on DPOS2.  The vessel replaced the controller with a spare held on-board.  At the time of the … Continue reading “Operating outside DP equipment class 2 requirements – DP incident”

Alerts iconSoftware update caused loss of generators in separate redundant groups

Case narrative A DP2 platform supply vessel (PSV) was set up on auto DP whilst conducting trials in open water after extensive upgrades.  The redundancy concept was based on two redundant groups with power generation, thruster supplies, and all DP consumers equally split between them.  Bow thruster 1 was supplied from a dual drive which … Continue reading “Software update caused loss of generators in separate redundant groups”

Alerts iconMaintenance during DP operations leads to – DP undesired event

Comments from the report: The oil level gauge was not reading the actual level.  The duty Engineer did not inform Bridge/DPO`s of maintenance on the header tank of stern thruster.  Future instruction was that the engine room would inform the bridge of scope of work of any maintenance to be carried out whilst the vessel … Continue reading “Maintenance during DP operations leads to – DP undesired event”