24th INTERNATIONAL CONGRESS OF THE AERONAUTICAL SCIENCES CONFLICT DETECTION AND ALERTING IN A SELF CONTROLLED TERMINAL AIRSPACE

A method for Conflict Detection and Alerting (CD&A) was developed as part the Small Aircraft Transportation System, Higher Volume Operations (SATS HVO) program at NASA Langley Research Center. The method addresses the specific problems and conditions of the concept of operations and uses a combination of state vector and procedure-based intent for conflict detection. The SATS HVO concept of operations has been developed to operate in small airports at self controlled terminal areas in near all-weather conditions. The concept uses vehicle-to-vehicle selfseparation logic and centralized ground based sequencing. The self controlled area (SCA) is a volume surrounding a SATS airport where pilots accept responsibility for self-separation. Flights operating in the SCA, during instrument meteorological conditions (IMC), are given approach sequencing information computed by a ground based automated system referred as the Airport Management Module (AMM). All participating aircraft must be Automatic Dependent Surveillance-Broadcast (ADS-B) equipped and able to communicate with the AMM. This paper proposes an innovative conflict detection method that combines linear state projections and intended approach paths based on the concept of aircraft conformance to a published procedure. The conflict alerting logic implements a multi-stage, non-symmetrical technique, also based on the conformance concept, that determines the order and time in which aircraft are notified of an impending conflict. Preliminary batch simulation results have shown that the proposed CD&A technique is as effective as a purely state based logic but issues significantly less false alarms. High fidelity batch simulations and human-in-the-loop experiments are underway to further assess the concept’s performance.