Validation of Extended Hybrid Surveillance

Extended Hybrid Surveillance is a surveillance technique allowing TCAS to track some intruders using ADS-B reports and thus considerably reduce utilization of the 1090 MHz channel. This new surveillance method can be used if the intruder is not projected to be near collision threat and is qualified according to specific criteria. Unlike previously defined Hybrid Surveillance, Extended Hybrid Surveillance may not use active interrogations to validate the passive data. This paper presents first validation results of the system (implemented to meet the recently published standard), which combines using Active (conventional), Hybrid, and Extended Hybrid Surveillance. The validation objective was to assess the overall system behavior as well as evaluate the achievable benefits in terms of saved Mode S interrogations. The presented work is outcome of SESAR project 9.47 entitled “TCAS Evolution”. Data used for validation was recorded during a set of first worldwide flight tests of this capability performed during 2014.