On Vessel Schedule Delay and Its Recoveries in Liner Services Using AIS Data

Maintaining the reliability of maritime transport is important as it plays an essential role in the world’s logistics. Shipping companies must also ensure the quality of liner service from the viewpoint of punctuality, as failure to take appropriate action against transport delays can lead to significant financial losses. This study quantitatively analyzes the behavior of containerships in response to global transport delays in 2021 caused by the COVID-19 pandemic using Automatic Identification System (AIS) data and port call history data. This study first comprehensively reveals the delay of containerships in 2021 by highlighting the increased variability in vessel arrival times, decreased handling capacities in specific ports, and increased navigation and anchorage times. Subsequently, this study clarifies how vessels recovered their schedule by increasing ship speeds or skipping some ports. We found vessel speeds susceptible depending on their delay in some specific voyages, such as long-distance cross-regional navigation.