Thursday, January 13, 2011

Lessons Learned—Vessel Breaks Mooring Lines, Grounds—Part II

Excerpt from U.S. Coast Guard Proceedings of the Marine Safety & Security Council magazine. Click here for part I.

The Analysis
One A/B was working his first time in Cook Inlet after only 27 days aboard the vessel. As he worked the lines alone, his inexperience, combined with the lack of a seasoned A/B to provide him with the necessary guidance on the vessel’s equipment, contributed to his releasing too much tension. This caused a strain on the other mooring lines, which then compromised the strength of the entire mooring system.

Contrary to Coast Guard ice guidelines, there was no seagoing watch present on the bridge and the engines were not kept in immediate standby.

Additionally, the operations manual at the facility necessitated mooring lines be doubled or tripled during extreme ice conditions, and required that transfer operations should be suspended within two hours of max flood or max ebb currents during ice conditions. The incident occurred within one minute of the calculated max flood.

The master’s failure to ensure that the vessel’s moorings were strong enough to hold during all anticipated conditions resulted in the Coast Guard seeking a two-month suspension of his license and merchant mariner document.

As a direct result of this grounding, the Coast Guard continues to conduct spot-checks of vessels mooring at Cook Inlet facilities to ensure they take adequate extreme weather precautions.

These spot-checks include the following tasks:

  • Affirm proper vessel mooring.
  • Ensure all deck personnel are equipped with protective winter clothing.
  • Conduct an operational test of steering gear.
  • Confirm a properly heated wheelhouse and living quarters.
  • Conduct an operational test of ballast and emergency fire pumps.
  • Conduct an operational test of all deck mooring winches and anchor windlasses.
  • Confirm that a heated medium is available to primary and secondary sea chests to prevent icing.
  • Confirm that all systems and machinery will be operable in ice-filled waters and air temperatures to -40°F.
  • Ensure that the emergency generator is fully fueled and the generator is set to automatic mode and do an operational test of the generator, conducted by setting it to “manual” and back.
  • Conduct a briefing for the vessel’s personnel to discuss the requirements needed to maintain compliance with ice guidelines while at the dock or underway.

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