1Shared-Separation: Empirical Results and Theoretical Implications

The concept of free flight is intended to provide increased flexibility and efficiency throughout the global airspace system. This idea could potentially shift aircraft separation responsibility from air traffic controllers to flight crews creating a ‘shared-separation ’ authority environment. A real-time, human-in-the-loop simulation study was conducted using facilities at the National Aeronautics and Space Administration (NASA) mes Research Center and the Federal Aviation Administration (FAA) William J. Hughes Technical Center. The goal was to collect data from controllers and pilots on shared-separation procedures, information requirements, workload, and situation awareness. The experiment consisted of four conditions that varied levels of controller and flight crew separation responsibilities. Twelve controllers and six pilots were provided with enhanced traffic and conflict alerting systems. Results indicated that while safety was not compromised, pilots and controllers had differing opinions regarding the application of these new tools and the feasibility of the operational concept. These results are discussed within the theoretical framework of the Hollnagel (1993) Contextual Control Model. Future research in the shifting of separation authority and the requirement for intent information is recommended