Question 1

The cargo operations were eventually completed safely. No contact was made with the platform. The master is reviewing reporting obligations. The blackout caused: total loss of DP for 4 minutes, drift to 42m from the platform, and manual joystick recovery with two thrusters. No injury and no damage.

Which bodies must be informed of this incident and within what timeframe?

Accepted Answer

Reporting obligations include: the flag state (many require DP incidents to be reported regardless of outcome), the vessel's classification society (loss of class-relevant system capability), IMCA (if the operator is a member — voluntary reporting is how the industry learns), the client/installation (they were directly involved), and the company SMS non-conformity system. Timeliness varies by flag state but most require initial report within 24 hours A total blackout on a DP2 vessel drifting to 42m from a live gas platform is a significant DP incident regardless of the absence of contact. Flag states increasingly require DP incidents to be reported — the UK MCA, Bahamas, Marshall Islands, and others have issued DP incident reporting guidelines. Class societies need to know because the blackout may reveal FMEA non-conformities requiring investigation. IMCA's industry incident reporting system (which generated 217 submissions in 2024) depends on companies reporting events like this one — the learning value to the entire offshore industry is the mechanism that prevents the next vessel from drifting into a platform. "No damage" is not the reporting threshold — the incident is the reporting threshold.

Question 2

EMERGENCY SCENARIO — DP2 PLATFORM SUPPLY VESSEL

Vessel: Offshore PSV, DP2 class. Location: 80m from a fixed gas platform, holding position to deliver equipment. DPO on watch. Three DGNSS references active, two gyros operational (Gyro 3 offline for calibration). Sea state: 1.8m, wind 22 knots SW. Thruster configuration: full complement, open bus, consequence analysis test passed 90 minutes ago.

Work through the following 10 decision points in sequence — each builds on the last.

--- POINT 1 OF 10 ---

Without warning, the main generator (G1) trips offline. The DP system sounds an alarm. The bus is still open. The remaining generators (G2, G3) are online and picking up load. Position is currently stable.

What is the DPO's first action?

Accepted Answer

Immediately check the power status panel to confirm which generators are online, verify the bus is still open, and assess whether the remaining power configuration still meets DP2 WCF requirements in the current conditions The DPO's immediate response to any system alarm is active assessment — not passive waiting. Waiting for auto-restart risks losing 30 seconds of situational awareness during which the power situation may worsen. Closing the bus tie immediately is the most dangerous response — it connects both power sections and creates a common cause failure risk. Waiting for the engine room assessment before taking DP action passes decision authority to a team who cannot see the DP system status. The DPO must immediately understand what power is available and whether DP2 capability is maintained with the current thruster configuration and reduced generation.

Question 3

20 seconds after G1 tripped, G2 begins overloading as it attempts to absorb G1's load. G2's frequency is dropping. The power management system (PMS) is attempting to auto-shed non-essential loads. The DPO has confirmed that DP2 WCF may not be maintained if G2 also trips.

What is the DPO's priority action at this point?

Accepted Answer

Inform the master immediately, declare a DP Alert, begin controlled manual thruster reduction on the most loaded thrusters to reduce electrical demand and help stabilise G2, while simultaneously monitoring position At this point the scenario is escalating — the DPO cannot wait for automated systems to resolve it. The master must be informed immediately (this is now a DP Alert situation). Controlled manual reduction of thruster demand on the highest-loaded thrusters removes electrical load while preserving position-keeping capability better than an across-the-board minimum power command (which removes all fine control). Closing the bus in a G2 overload situation is the worst possible action — a fault propagating from G2 would then take out all power simultaneously. The PMS may not shed enough load fast enough; DPO manual intervention is appropriate.