Tactical Conflict Alerting Aid for Air Traffic Controllers

The Tactical Separation-Assisted Flight Environment (TSAFE) is designed to alert air traffic controllers to imminent conflicts (predicted loss of separation within approximately 3 minutes). It generates constant-velocity ("dead-reckoning") trajectory predictions similar to those generated by Conflict Alert, the legacy system that currently performs the tactical alerting function in the United States. Unlike Conflict Alert, however, it also generates predictions based on pilot intent as specified in the latest flight-plan route and assigned altitude. The intended route is not always known, however, because controllers sometimes neglect to enter route amendments into the host computer. Hence, both the constant-velocity predictions and the flight-plan-based predictions are checked for conflicts. To reduce false alerts, the time horizons of the two predicted routes are a function of the degree of conformance to the current flight-plan route. Alerting performance was tested using archived tracking data for 100 actual operational errors, and TSAFE was found to provide timely warnings significantly more consistently than Conflict Alert. When tested on a sample of general traffic data, TSAFE was found to produce substantially fewer false alerts than Conflict Alert.