Investigating the causes of vessel besetting in the ice channel in the Baltic Sea using AIS data and Sentinel imagery

Icebreaking assistance in ice-covered waters involves the use of icebreaker(s) to create an ice channel for the assisted vessel(s), which facilitate the vessel(s) navigation in ice conditions. However, assisted vessels that follow the icebreaker may become beset in the ice channel. In April 2021, vessel A navigated in the Baltic Sea with the assistance of icebreakers B and C, during which vessel A experienced three instances of besetting within the ice channel. This research endeavors to examine the underlying causes of vessel besetting within the ice channel by analyzing automatic identification system (AIS) data and ice condition data. The preliminary findings indicate that the primary factors that contributed to that besetting were the severe ice conditions and considerable distances between the icebreaker and the vessel. Evidence to suggest that the channel radius influenced the besetting have not been found, but it is hypothesized that the curvature of the ice channel may have impacted the maneuvering capabilities of icebreaker C in the third beset instance.