Blackout leaves survey vessel drifting with no anchor

The total power-out happened in the Scottish Firth of Forth on the site investigation vessel Kommandor Susan, owned by Gardline Shipping at the time of the incident in January 2025 but by Hays Shipping when she was given a major overhaul in 2019.

The MAIB report says Hays had limited oversight of the overhaul, and it has now been found that the components used were not OEM parts and had not been approved by the OEM manufacturer. They wore out prematurely and in the incident, a diesel generator suffered a catastrophic mechanical failure, which triggered an engine room fire and subsequent loss of all power.

The crew managed to put out the fire but could not deploy anchors because the anchor windlasses relied on electrical power, and the vessel drifted eastwards.

Limited propulsion was eventually restored, allowing the vessel to return to harbour without injuries.

Weak substitutes

“The vessel’s former owner had minimal oversight of the overhaul process and assumed that original equipment manufacturer parts were used,” says the report. “This lack of verification meant that the presence of substitute components remained undiscovered and was not communicated to subsequent owners.

“Additionally, the vessel’s anchoring procedure did not account for the risk of power loss, leaving the anchors inoperable during the emergency.”

The substitute bearings exhibited weaker material bonding than approved OEM parts, while the extended maintenance intervals applied to the engines were only valid for genuine components. Investigators concluded the combination of non-approved parts and extended service intervals was a critical factor in the failure.

The investigation also identified deficiencies in contractor oversight. The vessel’s former owner assumed OEM components had been installed during the overhaul but did not verify this, allowing the substitute bearings to remain undetected through a subsequent change of ownership.

The MAIB also found the vessel’s emergency procedures had not considered the consequences of a total power failure on anchoring capability. The report recommended operators ensure risk assessments address the loss of electrically powered safety-critical equipment and urged owners to strengthen contractor assurance processes to verify that replacement parts meet OEM specifications.

“The vessel’s owner, Gardline Shipping Limited, has since rebuilt the affected engine, and overhauled all other generator engines on board Kommandor Susan, with original equipment manufacturer parts,” the report says.