Aircraft in the future ATM system - exploiting the 4D aircraft trajectory

The aircraft in the future ATM system (AFAS) project investigated the possibilities to safely integrate and put into operation a selection of technologies considered beneficial for executing short-haul flights within European airspace in the near future. The project was set within the Fifth Framework Programme for Competitive and Sustainable Growth of the European Commission, with airbus being the leader of a consortium incorporating the expertise of companies in the fields of avionics, ground equipment technology, airline operations, air traffic management (ATM) research and other related fields. The present paper will describe the elaboration of the AFAS operational concept. This concept is based on: strategic datalink services for sharing of information and negotiation of planning constraints between air traffic control (ATC) and the aircraft in order to ensure planning consistency; use of the 4D aircraft trajectory information in the flight management system for ATC operations. Furthermore, the paper presents the results of human-in-the-loop real-time simulation exercises carried out at two European ATM research institutes. The simulations investigated the ground infrastructure necessary to support the new avionics package. It could be shown that the use of 4D-trajectory information in combination with refined methods for flight planning and execution will lead to more precise flight operations for aircraft that have to satisfy narrow arrival constraints. In addition, it was possible to demonstrate in conjunction with a number of fast-time simulations, that the necessary methods for prioritisation of such constrained flights do not have any negative effects on the remaining traffic.