Development of optimal scheduling strategy and approach control model of multicopter VTOL aircraft for urban air mobility (UAM) operation

Abstract

Urban air mobility (UAM) is emerging as a new alternative to solve the traffic problem in the metropolitan area. Industries and government agencies are preparing for the future UAM system and operation. A new ATC (Air Traffic Control) strategy or aircraft separation method that reflects flight characteristics of multicopter VTOL (Vertical Take-off and Landing) aircraft is required. Particularly, approach control around the vertiport is one of the essential issues for the safe and efficient operation of UAM, and strict safety standards are required for service in populated urban areas. In this study, the concept of holding points where multicopter aircraft can hover is introduced, and three scheduling strategies for arriving aircraft are developed and evaluated by comparing the on-time performance (OTP) with hovering time and ground time. BQA (Branch Queuing Approach), SBA (Sequence-based Approach) and, SBAM (sequence-based approach with moving circles) models are proposed and compared. BQA model prioritizes airspace safety by limiting the aircraft's travel path; SBA model allows the aircraft to move freely within the airspace and prioritizes aircraft's arrival sequence; and finally, SBAM adds the moving circle concept to the SBA model. For each model, OTP and loss of separation (LOS) risk of the proposed models are found and they are compared by simulations. The simulation result shows that SBA and BQA have similar punctuality performance and BQA model with no LOS risk is the most efficient approach control model for multicopter VTOL aircraft of UAM.