Analysis of Alert Rate Changes and Protection Associated with Active BCAS (Beacon Collision Avoidance System) Threat Criteria

摘要

Protection afforded by active BCAS is analyzed in terms of the possible violation of a prescribed minimum allowable miss distance standard. Part of the analysis is based on a theoretical distribution of aircraft velocities at low altitudes in a terminal area. This velocity distribution is taken from a mathematical model of air traffic similar to one used previously to fit the Mitre Los Angeles Standard Traffic Model. It is shown that the present version of the mathematical traffic model fits data derived from the Houston Intercontinental Airport environment. That dat was originally extracted from ARTS tapes and processed by Mitre to determine, among other things, the effect of various BCAS alert logic parameter choices on alert rates that would have occurred at Houston if the aircraft involved had been equipped with BCAS. This paper demonstrates that the mathematical model can be used to predict accurately changes in the Houston alert rates due to changes in BCAS alert logic parameters. Keywords: BCAS (Beacon Collision Avoidance System), Air Traffic control terminal areas, Midair collision avoidance, Alarm rate, Alert criterion, Alarm criterion, Air traffic model, Modified tau, Vertical avoidance maneuver.