AwSim Flight Data Processor Architectural Highlights


The purpose of the Flight Data Processor (FDP) is to provide the core services of an ATC system: ICAO or NAS message parsing, syntax checking, route conversion, fix time estimation, conformance monitoring, and creation and updating of a flight database with the capability of exporting updated 4D-profiles to any external clients.


The program is a platform independent console application written in C++ using Object Oriented technology. FDP supports two run modes: a) a real-time process connected to a live data feed used primarily as an operational ATC system, and b) an off-line batch mode used for data analysis, live data re-play, and as a source of 4D-trajectories for the AwSim metrics pipeline. FDP keeps a flight database in memory that is updated with any movement coordination and/or control message received by the system. Running in real-time mode, FDP uses socket interfaces to receive ATC messages (input) and to send trajectories (output) to the client application. The main output produced by FDP is trajectories. Trajectories are generated every time a new flight enters the database and every time a flight is updated as a result of processing a message received for the flight. As an off-line tool FDP uses file i/o. Configuration of the system is done via *.ini files. The primary input to FDP is a stream of ICAO Air Traffic Services messages text messages, and with the addition of the ASD Driver process FDP can also handle the US ETMS message set.

The Flight Data Processor (FDP) together with the ASD driver adds the capability of connecting to live traffic and subsequent generation of trajectories resulting from processing of flight plans and related ETMS messages. ASD is the main driver that provides an interface with the FAAs Volpe Feed (live data source for the ETMS system). FDP is the Flight Data Processor where NAS and ICAO flight plans are processed to produce trajectories. Having the capability to capture live traffic is useful to a) establish air traffic baselines, b) fine tune the trajectory simulator (TRS) to make its output more realistic, c) provide a trajectory database for a 'bootstrap' generation mechanism, d) perform systematic metrics studies of current air traffic.

The ASD driver establishes a socket connection to the FAAs Volpe Center ASDI Server over a TCP/IP enabled client. All NAS ETMS messages (AF, AZ, DZ, FZ, RZ, TZ, and UZ) are read from the socket port and passed to FDP. FDP parses these messages, performs syntax checking, route conversion, boundary crossing, and fix time estimation. The end product of FDP is a 4-dimensional Trajectory object ready to be sent to the rest of the AwSim pipeline. FDP requires adaptation data (i.e. fixes, airports, airways, airspaces, etc), which the user customarily provides and maintains. FDP is provided with an initial (US) adaptation and maintenance of this can be provided under engineering service.