202035 Anchor lost in heavy winds

13 May 2020 MARS

A tanker in ballast dropped anchor and six shackles of chain in the early evening to await a berth for loading. Winds were force 4, but stronger winds were forecast so the main engines were kept on standby.

Early the next morning, with winds now gusting to force 6-7, the OOW deduced that they were dragging anchor as the vessel had departed its swing circle. The anchor party mustered on the foredeck, but by the time they had done so, the vessel had already reached a speed of about 2.8 knots.

Once at the anchor station, the personnel realised that the vessel was not dragging anchor, but that the anchor had been lost. The main engine was engaged and the vessel was able to safely make its way out of the anchorage.


Lessons learned

  • Anchors and associated gear are for holding ships in light to moderate weather conditions. For more adverse weather, drifting or slow steaming (hove-to) would be the safer option.
  • Vessels in ballast are particularly vulnerable to wind effects. This should be considered when anchoring.
  • Information concerning loads on anchor systems can be found at https://bit.ly/3gKVqlV