Study of Parametric Rolling Event on a Panamax Container Vessel

Abstract

In January 2003 the Maersk Carolina, a Panamax container vessel, encountered a storm in the North Atlantic en route from Algeciras, Spain, to Halifax, Nova Scotia, Canada. The vessel experienced gale-force winds and seas in excess of 10 m. During one particularly violent rolling and pitching event, the vessel quickly and unexpectedly began rolling upwards of 47 degrees. During this incident 133 containers were lost overboard, and 50 others sustained moderate to severe water damage but remained on board. Cargo claims exceeded $4 million. The vessel itself sustained moderate structural damage. Results of a simulation and modeling study of the event are presented, and they indicate that the vessel had experienced parametric rolling, a little-understood and unexpected risk for certain container vessel designs. The simulation further showed that in tiers where containers were lost, excessive compression forces acting on the lower on-deck container tiers exceeded the strength of the corner posts, which would cause containers in these tiers to collapse and result in a catastrophic failure of the lashing system. All simulation results correspond closely to what was observed on the vessel. A brief introduction to vessel design and weather factors leading to parametric rolling is provided. New wave sensing technology, advanced on-board analysis software similar to that used in the Maersk Carolina study, and precise vessel motion measurement technology currently under development are described. These innovations will allow masters to make more informed navigational decisions and avoid parametric rolling events in the future.