Vessel Motions and Work Interruptions Aboard a Fast Rescue Craft

Abstract

A set of field trials were carried out aboard a Canadian Coast Guard fast rescue Rigid Hull Inflatable Boat. The vessel was outfitted with a data acquisition system to collect vessel and engine performance data and trialled in three wave conditions (approx. Beaufort 2 to 7). This paper focusses on the methodologies and results for calculating and investigating Motion-Induced Interruptions (MIIs). MIIs due to lateral and longitudinal overbalancing and sliding were investigated using the counting of motion events which are expected to cause an interruption, supported by a statistical analysis and examination of the distribution of the MII data. We conclude that MII assessments of small, light, high-speed craft such as the one studied should include longitudinal acceleration and pitch angle, typically assumed to be non-influential in MII assessments. Statistical treatments have promise for analysis of field-acquired MII data.