A Method of Detecting Potential Loss of Separation in Oceanic Airspace from Surveillance Data for Airspace Evaluation

Abstract

Step climbs of flights in oceanic airspace may be delayed by potential conflicts with other traffic for extended periods of time, with a resulting fuel burn penalty, and nearly 30% of oceanic flights departing from Tokyo facing delay in receiving step climb request approvals. Fast-time simulation evaluation of proposed changes to oceanic airspace design or flight operations requires a method that can identify potential step climb-blocking from track data. This study proposes a new algorithm to detect potentially conflicting traffic that may block step climbs from track data with high reliability by incorporating complex performance-based oceanic procedural separation rules. The proposed algorithm was able to detect conflicting traffic in two thirds of cases where step climb requests were not approved by air traffic control, similar to the performance of a human expert. The algorithm was also applied to the detection of PLoS (Potential Loss of Separation) in oceanic airspace. Comparison of the algorithm with a previous PLoS detection method using flight trajectories generated by fast-time simulation showed that the previous method could underestimate the number of PLoS events and their duration by as much as 25-60%. The new algorithm will therefore contribute to more accurate fast-time simulation studies of oceanic air traffic control by improving both step climb blocking detection and PLoS evaluation.