Field Evaluation of the Tailored Arrivals Concept for Datalink-Enabled Continuous Descent Approach

Abstract

Allowing aircraft to descend uninterrupted at low engine power, continuous descent operations promise to maximize fuel efficiency while minimizing environmental impact. Tailored arrivals is a concept for enabling continuous descents under constrained airspace conditions by integrating advanced air and ground automation through digital datalink. Operational trials were completed in January 2007 involving transpacific flights into San Francisco during early morning hours. Leveraging newly deployed Federal Aviation Administration automation in the oceanic environment, trajectory-based clearances were transmitted by datalink to Boeing 777 aircraft equipped with future air navigation system avionics. NASA's prototype ground-based automation for high-density arrival management tailored trajectory clearances to accommodate artificially imposed metering constraints. Upon sharing wind and descent-speed-intent data, ground-based and airborne automation were found to predict meter-fix arrival times to within a mean accuracy of 3 s over a 25 min prediction horizon. Corresponding mean altitude and alongtrack prediction errors of ground-based automation were 500 ft and 1:3 n mile, respectively, in comparison with surveillance truth. A benefits analysis suggests Boeing 777 fuel savings of between 200 and 3000 lb per flight (depending highly upon baseline traffic conditions) together with a corresponding reduction in CO 2 emissions of between 700 and 10,000 lb per flight.

Flight management system prediction and execution of idle-thrust descents

“…Most of the previous error analysis has focused on the distribution of the difference between operational arrival time at a waypoint and its prediction by the FMS or ground automation. A few such as [2,5] have 1.C.4-2 also considered the operational TOD prediction error. Using a simulator in the current research simplifies understanding how individual factors affect FMS predictions, which is beneficial in specifying accuracy requirements for the factors.…”

“…Due to the potential fuel savings and emissions reductions, enabling continuous descents is being pursued by several research groups [2][3][4][5][6]. Most of the previous error analysis has focused on the distribution of the difference between operational arrival time at a waypoint and its prediction by the FMS or ground automation.…”

Estimating Controller Intervention Probabilities for Optimized Profile Descent Arrivals

“…[1][2][3][4][5][6][7][8][9][10][11] The Efficient Descent Advisor [6][7][8][9][10][11] (EDA) is a decision-support tool for air-traffic controllers that can generate trajectory-based clearance advisories that define continuous descent approaches (CDAs). The advisories could also be generated so that they satisfy arrival-scheduling constraints and satisfy minimum separation requirements with respect to the predicted locations of other traffic.…”

CDA with RTA in a mixed environment

“…The Tailored Arrivals trials in San Francisco, Amsterdam, and Australia (in Sydney and Melbourne) have been using CPDLC route clearances generated dynamically and communicated to aircraft using the existing FANS CPDLC capability available on some equipped aircraft. [10][11][12] ADS-C is a means of extracting surveillance information from aircraft automatically, with the ground and airborne systems interacting without the need to bother the pilot or controller. The existing ADS-C functionality is focused on extracting current aircraft state information and some limited predicted state information.…”