CAUSES OF A VESSEL NAVIGATION DISRUPTION EVENT IN PACK ICE ON THE UMIAK I DURING MARCH 29-31, 2016

摘要

Pack ice pressure events and heavily deformed shear zone and land-fast ice conditions can cause serious disruption to vessel navigation through ice-infested waters, resulting in operational delays and increased costs due to downtime. Understanding the causes behind ice-related vessel navigation disruption events is critical to efforts to build predictive models for such events. These models will help offshore operators prepare for and avoid such events, thus decreasing downtime, lowering operational costs, and improving safety. This paper examines a three-day period during which operations of the Umiak I, an ice-strengthened vessel owned and operated by Fednav Limited, were repeatedly disrupted by extreme ice conditions in the shear zone offshore Voisey's Bay, Labrador. During March 29-31, 2016, the Umiak I was unable to make significant progress through the 9-10/10ths concentration ice in the shear zone and land-fast ice east of Voisey's Bay, and engaged in prolonged backing and ramming maneuvers in order to break through the pack. This study examines the regional metocean factors during the two months prior which led to the extreme conditions in the shear zone and caused the vessel navigation disruption event.