Definition

The Airborne Separation Assurance System is an aircraft system that enables the flight crew to maintain separation of aircraft from one or more aircraft and provides flight information concerning the surrounding traffic.

Background

New concepts for air traffic management, such as the ‘Free Flight’ concept, enable the flexible use of airspace by means of airborne determination of user-preferred trajectories thus allowing direct routing. These concepts are aimed at increased airspace capacity and reduced congestion. They may lead, however, to more complex traffic flows and increased controller workload. A solution might be to delegate the separation task to the pilot. Airborne Separation Assurance Systems (ASAS) can assist pilots in such “self-separation”. It is expected that ASAS will be effective, in terms of conflict resolution and reduced workload.

Observations

Two observations can be made with respect to automated airborne self-separation support: