The Repair That Was Never Going to Hold: Mazarine on Wolf Rock

An Hour, and a Pipe That Wasn't Going to Fix Itself

Mazarine was bound from Ringaskiddy, Ireland to Zeebrugge, Belgium on 10 July 2023 when a pipe elbow on the main engine's lube oil pump failed with a loud crack, spraying oil across the engine room. The main engine shut down automatically on loss of oil pressure. The Master's estimate: roughly an hour before the vessel, now without propulsion, would drift onto Wolf Rock — then about four nautical miles away.

Parallel, Not Sequential

What happened next is the part of this case worth studying. The Chief Engineer reported the engine's true state to the bridge immediately, including honest doubt that a quick repair would hold. The Master didn't wait to see whether the repair would work before acting — he dropped one anchor with eight shots of chain and notified Falmouth Coastguard that restarting the engine was unlikely, while the engineering team began a jury-rig repair in parallel: chain pullers, epoxy, fibre bandage, rubber mat, metal clamps.

By the time the repair had made partial progress, Wolf Rock was 0.7 nautical miles away. At 1023 the repair failed immediately under pressure, the crack widening all the way around the pipe's circumference. Five minutes later, Mazarine drifted onto Wolf Rock. At 1058 she pivoted free of the rocks, not taking on water, not listing dangerously.

A Second Repair, and an Honest Verdict

The Chief Engineer and Master decided to remove the failed elbow entirely and attempt a proper cast-iron weld repair with correct electrodes and technique. At 1246, after cooling the weld for thirty minutes, they restarted the lube oil pump — it cracked again, this time at only half normal operating pressure. A tug arrived around 1530 and towed Mazarine to Falmouth for drydocking.

What the Investigation Found

Transport Malta's Marine Safety Investigation Unit found no fault with either the bridge or engineering team at any stage. The root cause was the failure of the lube oil pipe elbow itself, which the report concluded caused structural damage in the underwater hull section, including perforations and deformation mostly on the port side. The investigation specifically noted the crew's actions concerning lights, shapes and AIS to show the vessel Not Under Command were timely, warning nearby vessel Ferro and allowing Falmouth Coastguard to notice the situation, and that the subsequent actions around passenger and crew safety and damage assessment were “timely and successful.” The investigation concluded that on-board repair of a crack of this nature on critical equipment was “extremely difficult, if not impossible,” and commended the crew's efforts under exceptionally challenging circumstances.

Recommended Actions

1. Anglo-Eastern Ship Management (NL) BV is recommended to investigate the level of vibration in the lube oil pipe elbow and take corrective action if needed
2. Report the true state of critical machinery to the bridge immediately, including honest uncertainty about whether a repair will hold — not after the repair attempt has concluded
3. Take early defensive action (anchoring, notifying the Coastguard) in parallel with an engineering repair attempt, not sequentially after the repair has failed
4. Display the correct NUC lights, shapes and AIS status promptly to warn nearby traffic and enable shore authorities to track the developing situation