InCAS is a PC-based interactive simulator for replaying and analysing Airborne Collision Avoidance System (ACAS) during close encounters between aircraft. It is designed for case-by-case incident analysis by investigators. InCAS reads radar data and provides an interface to examine these data in detail, removing any anomalies that may be present. The cleaned data are used to simulate trajectories for each aircraft at one-second intervals and these data are fed into a full version of the logic in the Traffic Alert and Collision Avoidance System, TCAS II (versions 6.04a, 7.0 and 7.1).
InCAS was developed by EUROCONTROL. As of January 2020, InCAS is no longer maintained nor distribiuted. A replacement tool Collision Avoidance Validation and Evaluation Tool (CAVEAT), incorporating ACAS X logic and featuring advance modelling functions has been developed.