Impact of RNAV terminal procedures on controller workload

Human factors studies have identified message frequency, message complexity (amount of information transmitted), and specific types of information as determinants of operational errors resulting from high workload. Miscommunications, at the very least, have the potential of narrowing the margin of safety. Reducing the number of routine controller-pilot communications, the amount of routine information transmitted, and the need for communicating information that is susceptible to errors helps foster a safe airspace environment and may also minimize workload incurred by the controller. This goal is supported by area navigation (RNAV) terminal procedures which capitalize on the enhanced navigation capabilities of current avionics technology. RNAV reduces the vectoring of aircraft from the terminal radar approach control (TRACON) boundary to the final approach for arrivals and from the runway to the TRACON boundary for departures through the design of fixed flight routes. A voice communication analysis was conducted for the terminal departure, terminal approach, and local tower controller positions at Hartsfield-Jackson Atlanta International airport. The analysis is comprised of three principle areas: 1) the amount of required communications; 2) the amount of information conveyed; 3) and the type of information conveyed. Voice data analysis results show up to 40% reduction in the amount of two-way communications and up to 50% reduction in the amount of information required.