TELSACS will examine collision avoidance technologies which would allow reductions in the standard minimum distances between aircraft to accommodate increased air traffic safely. Safety may be reinforced by inter-operable airborne and ground-based technologies. TELSACS will use identifiable weaknesses in current non-cooperative systems as the basis for a demonstration of novel inter-operable systems for airborne collision avoidance and ground-based short-term conflict alert. It will conclude with recommendations for safety standards for such systems.

To meet the increasing air traffic demand, a more automated Air Traffic Control environment is essential. The CNS/ATM (Communications, Navigation and Surveillance/Air Traffic Management) concept introduced by ICAO and based on new technologies - satellites and data link - will be able to solve the air traffic congestion problems. However, this increased traffic should not be satisfied to the detriment of safety.

Today, aircraft operational regulations restrict traffic by the way of vertical and horizontal separation standards which have been derived both from the limitation of CNS systems on the ground and in the air and from safety requirements. Improvements in CNS and airspace management will enable the introduction of reduced separation to accommodate increased traffic. However even if the rate of accidents is maintained at the current level, such increased traffic will result in a higher volume of accidents. Provision of cooperative airborne and ground safety nets i.e. ACAS (Airborne Collision Avoidance System) and STCA (Short Term Conflict Alert) respectively, will contribute significantly to the safe introduction of reduced separations.

This research addresses the airspace user needs for safety in Europe's crowded skies, by examining the shortcomings in the current technology non-cooperative airborne collision avoidance systems and sensors and ground based short-term conflict alerting systems. It will then demonstrate on an experimental platform, a new high integrity ATM environment characterised by co-operative ACAS and STCA systems and improved precision navigation.

The consortium that has been set up by joining on one side manufacturers and suppliers - for avionics and ground components - and on the other side end users - airlines and controllers - is well-built to lead the TELSACS project with the objective of defining recommendations for standards of safety systems - ACAS and STCA - profitable to the European Industry by the end of the century.

The TELSACS project will be carried out in two parts. Part I will cover the definition of users and system requirements enabling to develop a demonstrator. Part II will come to validation and recommendations for safety standards of ACAS and STCA systems.