Near-Term Solution for Efficient Merging of Aircraft on Uncoordinated Terminal RNAV Routes
It is anticipated that controllers will continue to vector traffic for spacing in the near-term where there are Required Navigation Performance (RNP) Area Navigation (RNAV) routes that merge prior to the final approach or on the final approach. Under moderate to heavy demand, this will negate many of the efficiency, throughput, and predictability benefits of keeping aircraft on the RNP RNAV routes.
Given the current level of metering and aircraft equipage, existing decision support automation and avionics capabilities can be used to keep aircraft on the routes and maintain benefits. In an earlier paper, we presented a suite of tools and concepts that address the merging and spacing problems arising from structured RNAV and RNP routes in the terminal environment. This suite of tools and concepts is referred to as Spacing of Performance-based Arrivals on Converging Routes (SPACR). The initial set of tools and concepts addressed the near-term merging and spacing problem, relying on existing cockpit and ground automation capabilities. In this paper, the tools and concepts are extended to the mid-term, requiring modest modifications of existing capabilities. SPACR includes applications of cockpit capabilities such as Flight Management System (FMS) Offsets and Required Time of Arrival (RTA) and ground automation functionalities such as the embedded ghosting function in the Automated Radar Terminal System (ARTS), Standard Terminal Automation Replacement System (STARS), and new STARS Graphical User Interface (GUI) functionalities. The previous paper presented an operational concept along with analytic and human-in-the-loop experiments for SPACR based upon the Converging Runway Display Aid (CRDA), a ground-based decision support tool, and the Lateral Offset capability in the cockpit.
In this paper, we extend SPACR to include a potential use of RTA and present an operational concept using it in conjunction with Lateral Offsets and CRDA. We present analytic results related to ground computation of RTA and matching that with the airborne computation. Results of human-in-the-loop experiments related to using SPACR to manage the final merge using only CRDA are reported. The paper concludes with a discussion of issues.
