UAS ground-based detect and avoid capability

The New York Unmanned Aircraft Systems (UAS) Test Site is developing a next-generation capability for supporting extended UAS beyond line-of-sight (BLOS) operations in airport terminal areas and in transition airspace. The Test Site has set up an instrumented test range to provide air traffic surveillance. This test range currently extends from the Griffiss International Airport, in Rome, New York, and its Class D airspace to about 40 NM to the north. To safely integrate UAS into civil airspace, a robust detect and avoid (DAA) capability is required. RTCA Special Committee (SC) 228 is incorporating ground-based detect and avoid (GBDAA) into minimum operating performance standards (MOPS) for UAS DAA in the current SC-228 Phase Two. SC-228 is also developing GB primary radar MOPS for detecting noncooperating air traffic. SC-228 Phase Two MOPS development scope supports civil UAS equipped to operate under IFR rules in extended UAS operations in Class D, E, and G, airspace, down to but not including ground operations. The guiding RTCA SC-228 Terms of Reference (TORs) focus on both airborne DAA systems (with sensors onboard the unmanned aircraft) and GBDAA sensors. While the SC-228 DAA MOPS scope is limited to large UAS operating under IFR, this paper makes a case that SC-228 MOPS-compliant GBDAA systems can also support small UAS operations in Very Low Level (VLL) airspace. The New York UAS Test Site Griffiss test range system employs multi-sensor fusion, using a combination of primary radar, wide area multilateration, and ADS-B, to track both cooperative and noncooperative air traffic. The system operates in combination with other dedicated air traffic surveillance sensors, including airborne DAA sensors. The system incorporates data collection, storage, and analysis capabilities supporting UAS integration into terminal and transition airspace, with live, virtual and constructive (LVC) simulation capabilities. By repurposing and leveraging mature systems such as ASDE-X and ASSC, the New York UAS Test Site not only avoids development of completely new prototype systems but also secures the advantage of built-in system health and performance monitoring. This paper supports the argument that dedicated capabilities such as those under development at the New York UAS Test Site are necessary to support development of concepts of operation (ConOps) and performance standards for future certification of UAS DAA systems. An instrumented test range will assist in validation of DAA system performance standards. The paper concludes with an example of how multi-sensor fusion in a range instrumentation system can be employed to make the safety case for beyond line-of-sight (BLOS) UAS operation.