Changes in roles/responsibilities of Air Traffic Control under precision taxiing

In support of the NASA NGATS (Next Generation Air Transportation System) ATM (Air Traffic Management) Airportal Program, a realtime simulation study investigated the changes in roles and responsibilities for tower controllers brought about by the introduction of a new automation tool to achieve precision taxiing. The prototype tool, GoSAFE (Ground Operation, Situation Awareness and Efficiency Flow), is part of a future surface concept. This future surface concept envisages that future surface operations will involve taxi clearances containing precisely timed taxi routes. The study was conducted in two parts: (1) the first phase was used to identify issues with the original control jurisdiction that arose due to the introduction of increased surface traffic and automation in the tower, and (2) the second phase was used to design new areas of jurisdiction in coordination with the introduction of the automation technology and to test this new partnership. Four retired controllers participated in a Human-in-the-Loop real-time simulation study based on the Dallas/Fort Worth (DFW) International Airport (East side only). The controllers interacted with the tool under two conditions - one using datalink and another using voice to issue and deliver clearances to the pilots. Phase-1 data analysis results showed a significant difference in the average workload reported at different controller positions, with the local east controller being particularly busy. Phase-2 data analysis results indicated a more balanced redistribution of workload and communications among the controller positions. Comparison of the two phases has been described in the results section, which includes an analysis of the dependent measures of workload, situation awareness, and nature of communications. Comparison of the two conditions was also done for phase-2, for some of the dependent measures. The results suggested that changes in roles of new automation and human operators will need to be considered - when designing procedures.