Enabling Advanced Continuous Descent Approaches: Results of the European Project OPTIMAL

Abstract

This paper describes the development and implementation of environmentally efficient CDA techniques in a future operational environment. It consists of two parts. The first part reports about operational aspects of integrating CDAs in an Amsterdam Airport Schiphol high density traffic scenario. The efficient CDA operation in such a busy traffic environment is promoted by the combined use of new and/or already available enabling airborne and ATM technology. This in-cludes airborne tools, such as FMS CDA functions, cockpit display cues, and im-proved ATC tools by means of accurate arrival management, air-ground data-link and controller sequencing aids. The simulations involved both flight crews and air traffic controllers showed promising results with respect to the feasibility of the concept to achieve high density CDA traffic flows. Whereas this kind of operation still puts some restrictions on aircraft flying the CDA and thus, do not allow for a fully optimised approach profile, the second part of this paper explains opera-tional concepts and airborne functions that will allow optimised CDAs in high density traffic situations. It demonstrates that with the developed FMS functions an optimised CDA can be flown in 4D so that e.g. in a “Late-Merging-Point” sce-nario, a given RTA can be met with high accuracy. Flight trials with DLR’s test aircraft ATTAS, a modified VFW 614 and with DLR’s Advanced Flight Man-agement System onboard, proved a highly accurate predictability of 4D optimised CDA trajectories.