4D-trajectory-based operations (where "D" stands for Dimensional) are proposed by SESAR 1 and NGATS 2 as the fundamental cornerstones of Air Traffic Management (ATM) system improvements of the future. Various research initiatives such as PHARE 3 [1] have long described and prototyped these ideas of integrated air-ground ATM. However, because the broad implementation of this concept requires significant harmonized development of both air-and ground-based technology, progress has been limited. Nonetheless, the avionics industry has implemented initial capabilities to manage the fourth dimension, i.e. time, called Required Time of Arrival (RTA). The paper summarizes the results obtained from a EUROCONTROL study on the availability, characteristics and performance of the Required Time of Arrival (RTA) function in existing Flight Management Systems (FMS).The RTA study is first discussed in the context of ATM, proposing some guiding premises as to how the time management function should be developed. As a consequence, the RTA study focused on performance during descent, using different FMS modes. A brief discussion of related EUROCONTROL projects has also been added. Test results from a number of sessions on Boeing 737 and Airbus A320 flight simulators are then presented. The evaluation included an assessment of the impact of wind on RTA, as well as some observations about the human machine interface aspects. Lastly, conclusions and recommendations for further development are proposed.
4D-trajectory-based operations are proposed by SESAR 1 and NextGen 2 as fundamental cornerstones of Air Traffic Management (ATM) system improvements of the future. An airborne Required Time of Arrival (RTA) function is seen as an initial enabler to allow better and more accurate planning of aircraft arriving, for example, at airspace sector boundaries or at the entry of a Terminal Area (TMA). Today, not all aircraft are equipped with RTA. In addition, aircraft have varying FMS trajectory prediction performances, varying levels of flight guidance functions (for example VNAV) and some aircraft do not have auto-thrust. All these factors may have an impact on the ability of an aircraft to fly a trajectory with a time constraint.To assess the feasibility of implementing arrival time control in an existing aircraft without excessive hardware modifications, an experimental FMS with RTA capability was developed and coupled to an existing Airbus A330 flight simulator at the scientific research facility of the Berlin Institute of Technology.A series of flight simulations was performed, using the RTA function in combination with different vertical profiles and different levels of flight guidance and automation. Some flights were flown using manual pitch control and without auto-thrust. Nearly all flights achieved an arrival time error of less than 10 seconds. Minimum flight guidance requirements were identified as an indication of the required calibrated airspeed (CAS) in the primary field of view of the pilot and an indication of the deviation from the reference vertical profile (VDEV). Finally a new RTA algorithm was designed to reduce the magnitude of the speed variations and was tested by means of fast-time simulation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.