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Co-Operative Air Traffic Management: Concept and Transition

Co-Operative Air Traffic Management (CO-ATM) is a concept under exploration at NASA Ames Research Center for transformation of aircraft and air traffic management operations towards the Next Generation Air Transportation System (NGATS). A goal of the CO-ATM concept is to provide a scalable framework to significantly increase NAS capacity and efficiency while maintaining safety. A second goal of this concept is to provide airspace users with increased flexibility in managing their operations. The concept aims at achieving substantial capacity and efficiency benefits through improved information exchange and changes in roles and responsibilities. It builds on lessons learned from Distributed Air/Ground Traffic Management (DAG-TM) research, and addresses identified safety, coordination, automation and mixed equipage concerns. CO-ATM provides a transition path from the current system to the next generation with gradual shifts in roles and responsibilities and incentives for aircraft operators to equip. CO-ATM envisions sector controllers controlling conventional aircraft along predictable flight paths and area controllers coordinating strategic trajectory changes with flight crews of equipped aircraft in the same airspace via data link. Area controllers operate with extensive automation support for conflict detection and resolution and traffic flow management. Flight path changes are automatically shared as 4D trajectories between area and sector positions. Routine tasks like handoffs and transfer of communication are conducted by the automation. Equipped aircraft may be cleared to operate at different levels of autonomy. Tasks like aircraft-to-aircraft spacing may be delegated to the flight crews by the controller. Flight crews of equipped aircraft can coordinate preferred trajectories for traffic flow constraints with the area controller or operate at higher levels of autonomy, if desired and authorized. The paper reviews plans and concepts for the NGATS and relevant research findings from DAG-TM studies. It introduces the CO-ATM concept in detail and presents a possible transition path in line with ongoing research at NASA Ames, addressing the integration of trajectory based operations and Airborne Separation Assistance Systems (ASAS). This concept is currently in its definition and exploration phase and is in line with research funded in the NextNAS project of NASA's Airspace Systems Program.