Validating the FACTS2 Air Traffic Simulation Framework

Abstract

At the heart of the modern air traffic management system there is the communication infrastructure that enables efficient aircraft guidance and safe separation in all phases of flight. However, although current systems are mature and generally providing a good service, they are suffering from the VHF band’s increasing saturation in high density areas. The EU and US, representing the two areas experiencing the most pressure, strive therefore for the sustainable modernization of the aeronautical communication infrastructure. Air traffic management communication shall transition from analog VHF voice communication to more spectrum efficient digital data communication supported by automated decisions of computer systems. This digitization of the air-ground communications infrastructure has to be evaluated carefully against the expected future air traffic to ascertain its sustainability and future-proofness. The accepted approach to this endeavor is to employ large-scale computer simulations. The most used method - generating synthetic air traffic with simplified flight trajectories from extrapolated flight plan databases - is largely accepted by the community as a good compromise between constant aircraft populations (too simplistic) and recorded real-world data (not available for the future). A combination of great-circle routes and simplified altitude profiles is deemed to provide sufficient fidelity for the simulation of long-range communication systems. However, the validity of this approach has yet to be investigated in detail. Although this investigation is certainly not possible in the general case we think that it can be performed for selected areas. In this paper we investigate the validity of synthetic air traffic generation for aeronautical communication system evaluation by comparing the results of our FACTS2 simulator to recorded flight data of Germany. FACTS2 is the German Aerospace Center's framework for aeronautical communication system evaluation.