Reliable Robotics has tested its Detect and Avoid (DAA) system for the Federal Aviation Administration as part of the Broad Agency Announcement program, conducting data collection flights in airport environments. The flight testing was designed to support the integration of large uncrewed aircraft systems (UAS) into the National Airspace System by evaluating their ability to maintain safety and operational efficiency across different classes of airspace, including terminal areas and traffic patterns.
The data gathered is intended to assist the FAA in finalizing certification standards for DAA systems, as well as to inform technical standards under development by industry groups. The testing campaign was conducted in collaboration with Virginia Tech Mid-Atlantic Aviation Partnership and included contributions from Sagetech, Collins Aerospace, and uAvionix.
Reliable Robotics’ DAA system is designed to assist remote pilots in maintaining safe separation from other aircraft by performing functions such as remaining well clear and executing collision avoidance maneuvers. The system is based on the FAA-developed Airborne Collision Avoidance System X (ACAS X), an evolution of the Traffic Alert and Collision Avoidance System II (TCAS II) used in commercial aviation. Variants of ACAS X include ACAS Xu, which is intended for autonomous fixed-wing aircraft.
According to the company, the FAA-contracted tests assessed operational thresholds between en route and terminal airspace environments and evaluated how the DAA system and ACAS X algorithms provide alerts and maneuver guidance to remote pilots in these contexts. The testing included both simulation-based Hardware-in-the-Loop evaluations and live flight scenarios involving scripted aircraft encounters.
One outcome of the testing was the identification of differences in system behavior between en route and terminal environments. The ACAS X algorithm demonstrated adjustments in response depending on the airspace context, reflecting operational differences between instrument flight rules (IFR) and visual flight rules (VFR) traffic. The system also demonstrated the ability to provide collision protection against both cooperative and noncooperative aircraft during low-altitude phases such as takeoff and landing.
Flight operations were conducted at Hollister Municipal Airport in California, where Reliable Robotics executed a series of controlled encounters to generate operational data. The company stated that such real-world data is difficult to replicate in laboratory conditions and is necessary to validate performance requirements for emerging DAA standards.
The collected data has been shared with RTCA Special Committee 228 and RTCA Special Committee 147, which are responsible for developing minimum operational performance standards for DAA systems and related technologies.
