Joint effort seeks to help reduce anchor losses, related damage

A new investigation suggests many anchor losses are avoidable and shed light on a potentially bigger issue: the need for crews to be aware of the environmental loads for which equipment is designed.

A rising number of anchor losses reported over the last several years prompted an investigation. The investigation was carried out by DNV GL, which provides classification and technical assurance, and software and independent expert advisory services to the maritime, oil and gas and energy industries; Gard, a shipowner-controlled provider of protection and indemnity, marine and energy insurance products; and The Swedish Club, a mutual insurance company owned and controlled by its members. 

“The root cause of many groundings and collisions, lost anchors are among the top five reasons for claims costs,” notes a joint statement issued last week. “Anchor and chain loss can often lead to collisions and grounding, which can result in additional damage to a vessel. Adding to the costs of anchor loss is the increasingly common requirement from port authorities that lost anchors are recovered,” the statement adds.

“One of the key takeaways of our investigation is the importance of the officers and crew being aware of the environmental loads their equipment is designed for,” says Håkon Skaret, senior principal engineer at DNV GL. “If these limits are not taken account of in shipboard anchoring procedures, there can be significant damage to the vessel – even beyond the loss of anchor and chain. Many anchor losses are avoidable, if the proper maintenance and handling procedures are adhered to,” Skaret contends.

Based on an analysis of damage cases involving anchor and anchor chain losses, the project partners identified the most frequent technical and operational causes, as well as some steps crews and operators can take to address them. Their observations include the following:

• The D-shackle is the technical component with the highest loss-causing failure rate, indicating it should be inspected whenever possible, with special attention paid to the taper pin. Securing the anchor tightly in the hawse pipe during voyage can help to avoid excessive vibrations that can cause the pin to come loose.
• The windlass brake is essential to control the pay-out of the chain, and many anchor losses are reported as a result of loss of brake power and uncontrolled release of the chain. Corrosion of the drum and wear of the brake band lining reduces brake capacity and it is, therefore, essential that brake tension is adjusted and liners replaced in accordance with the manufacturer’s instructions.

“The crew and officers need to be aware of the risks and assess them thoroughly, especially in heavy weather,” Skaret emphasizes.

“In almost half of the cases, we saw that environmental risk factors, such as the weather, strength of the currents and water depth, played a significant role in the loss,” he points out. “To help shipboard personnel in this respect, shipping companies can make sure that procedures for safe anchoring operations are implemented in their safety management systems.”