When Anchors Fail: A Real-Life Case of Dragging Anchor and Chain-Reaction Collisions
February 2024 brought to light another sobering reminder of how critical anchoring practices are to maritime safety. In a recent case study shared by the Britannia P&I Club, a seemingly routine bunkering stop turned into a multi-ship incident involving structural damage, communication lapses, and avoidable risk—all due to one critical failure: a dragging anchor.
⚓ The Incident: One Anchor, Three Ships, and a Chain Reaction
A 2,840 GT general cargo ship (referred to as Ship A) was en route to the River Humber for bunkering. Already compromised by the loss of its port anchor during a prior storm, Ship A was under a Condition of Class (CoC) directive to keep its main engine on standby while at anchor. Despite this, poor judgment and insufficient watchkeeping led to critical delays in responding to anchor dragging.
In worsening weather conditions and tidal currents of 2.7 knots, Ship A's anchor failed to hold at its designated anchorage. Within minutes, the vessel began to drift—heading straight toward a nearby research and survey vessel (Ship B) anchored just three cables away.
At 03:12, despite attempted evasive action, Ship A collided with Ship B, entangling anchor chains and leading both vessels to drift toward a third vessel, Ship C. By 03:20, a second collision occurred—this time, Ship A struck Ship C as the entangled trio struggled against wind and tide.
⚠️ What Went Wrong?
This was not simply a case of bad weather. Several systemic and operational failures were identified:
Inadequate Watchkeeping: The officer on duty failed to detect anchor dragging for nine critical minutes.
Poor Communication: There was no immediate alert to nearby vessels or the harbor authority.
Non-compliance with CoC: The master shut down the main engine against explicit instructions.
Inconsistent Company Procedures: Conflicting actions between Ship A and another company vessel, Ship C, highlighted a lack of standardized engine readiness protocols.
📚 Lessons Learned: Bridging Gaps in Anchor Safety
This incident provides vital lessons for fleet operators, shipmasters, and port authorities:
Anchor Watch Vigilance: Continuous, short-interval monitoring of position is essential—ideally with GPS anchor alarms enabled.
Engine Readiness Compliance: When under CoC or in adverse conditions, main engines must remain ready for immediate use.
Crew Training & SMS Clarity: Safety Management Systems (SMS) must clearly define readiness protocols and bridge responsibilities.
Proactive Communication: In any sign of anchor failure, prompt communication with nearby vessels and VTS is non-negotiable.
💡 Final Thoughts
This case serves as a cautionary tale of how one overlooked procedure can lead to a multi-vessel emergency. It underscores the real-world risks of dragging anchors, particularly in congested waters and rough conditions.
As maritime technology advances, solutions like A R G U S AnchorTAG that offer real-time subsurface awareness and anchor status feedback could become vital tools in preventing such incidents. Knowing what your anchor is doing—before it’s too late—can make all the difference.
📖 Source:
Case Study No. 22 – Dragging Anchor Leading to Multiple Collisions
© Britannia P&I Club, February 2024
Read the original report