SAFETY LOGIC SYSTEM ALERTS
Pilot/Controller Glossary with JO 7110.65BB, Change 3, effective July 9, 2026 · Official text on faa.gov
- ALERT-
- An actual situation involving two real Safety Logic tracks (aircraft/aircraft, aircraft/vehicle, or aircraft/other tangible object) that the Safety Logic System has predicted will result in an imminent collision, based upon the Safety Logic parameters.
- An actual situation involving a single Safety Logic track arriving to, or departing from, a closed runway.
- An actual situation involving a single Safety Logic track arriving to a taxiway.
- FALSE ALERT-
- Alerts generated by one or more false surface radar or cooperative surveillance targets, that the ASDE system has interpreted as real tracks and placed into Safety Logic.
- Alerts in which the Safety Logic System did not perform correctly, based upon the design specifications and Safety Logic parameters.
- Alerts generated by surface radar targets caused by moderate or greater precipitation.
- NUISANCE ALERT- An alert in which one or more of the following is true:
- The alert is generated by a known situation that is not considered an unsafe operation, such as LAHSO or other approved operations.
- The alert is generated by inaccurate cooperative surveillance data received by the Safety Logic System.
- One or more of the aircraft involved in the alert is not intending to use a runway/taxiway (helicopter, pipeline patrol, non-Mode C overflight, etc.).
- VALID NON-ALERT- A situation in which the Safety Logic System correctly determines that an alert is not required, based upon the design specifications and Safety Logic parameters.
- I NVALID NON-ALERT- A situation in which the Safety Logic System did not issue an alert when an alert was required, based upon the design specifications and Safety Logic parameters.