OKLAHOMA CITY – Vigilant Aerospace in Oklahoma City has completed a new series of flight tests of its FlightHorizon PILOT onboard detect-and-avoid (DAA) system, demonstrating new capabilities that support autonomous flights beyond a pilot's visual line of sight.

The company tested two versions of the system. A lightweight configuration uses an onboard transponder receiver and autopilot integration for operations in cooperative airspace, while a larger configuration adds onboard radar to detect aircraft that don’t carry transponders.

The demonstrations are part of a $1 million development project announced earlier this year with Oklahoma State University's Oklahoma Aerospace Institute for Research and Education (OAIRE). The effort also receives support from the Oklahoma Center for the Advancement of Science and Technology (OCAST).

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Detect-and-avoid remains a key hurdle for autonomous flight

As commercial and government drone operations expand, detect-and-avoid technology has become one of the industry's primary technical challenges. Aircraft operating beyond visual line of sight (BVLOS) must be able to detect nearby traffic, assess potential conflicts, and safely maneuver without relying solely on a remote pilot.

FlightHorizon PILOT was originally developed for the U.S. Air Force through a Small Business Innovation Research (SBIR) contract and incorporates technology based on two licensed NASA patents. The system is designed for both military and civilian uncrewed aircraft.

The latest civilian version integrates aircraft detection, target tracking, trajectory prediction, target correlation, and avoidance calculations on a compact single-board computer sized for small uncrewed aircraft.

"The future of aviation will largely be autonomous, which will require automatic onboard safety systems," said Kraettli L. Epperson, CEO of Vigilant Aerospace. "The new rules and standards emerging today are shaping how drones will integrate into the national airspace. Capabilities such as FlightHorizon PILOT are intended to help operators prepare for those requirements."

Flight tests expand onboard capabilities

Recent demonstrations focused on validating the system's ability to detect nearby aircraft, calculate projected flight paths, and generate automated avoidance commands during flight.

Engineers also evaluated radar performance and integrations with both multirotor and fixed-wing aircraft. The software automatically selects avoidance algorithms appropriate for each aircraft configuration.

Most of the testing took place at Oklahoma State University's Uncrewed Aircraft Flight Station.

The cooperative configuration relies on ADS-B traffic data for operations in airspace where aircraft are equipped with transponders. A second configuration adds compact onboard radar, allowing operators to identify non-cooperative aircraft that may not broadcast their position.

Both versions use the FAA's ACAS-X collision-avoidance algorithms to generate alerts and avoidance guidance. The system sends commands directly to the aircraft's autopilot while simultaneously displaying traffic information and recommended maneuvers on a ground-control interface.

Recent flights used an NDAA-compliant Group I hexacopter. Future testing will transition to a larger Group II fixed-wing aircraft capable of carrying payloads exceeding 60 pounds over distances approaching 300 miles. Vigilant Aerospace said the platform is intended for missions such as infrastructure inspection, wildfire response, search and rescue, and long-range cargo delivery.

Preparing for future BVLOS operations

FlightHorizon PILOT combines a single-board computer with onboard sensors, an autopilot interface, an ADS-B receiver, and optional radar. The system continuously tracks surrounding traffic, predicts flight trajectories, and calculates avoidance maneuvers when separation thresholds are threatened.

Flight testing also evaluated the software across multiple computing platforms and radar configurations, while optimizing the system for low SWaP-C requirements. The platform records detailed traffic and avoidance data and is being developed to support industry standards, including RTCA DO-365C and ASTM F3442-25, depending on system configuration.

The testing comes as the FAA continues developing rules for routine BVLOS operations. Draft Part 108 regulations would allow larger drones to conduct low-altitude flights beyond a pilot's visual line of sight under defined operating requirements. Those rules are expected to require some form of detect-and-avoid capability for many operations.

As autonomous aircraft become more common, onboard collision-avoidance systems are expected to play an increasingly important role in enabling routine commercial, public safety, and defense missions.

Development builds on earlier flight programs

FlightHorizon PILOT has undergone multiple development programs during the past several years.

Early flight demonstrations took place under an FAA research project with the Alaska Center for Unmanned Aircraft Systems Integration (ACUASI), where the system supported long-range pipeline inspection flights under an FAA BVLOS waiver.

The technology later advanced through an Air Force Research Laboratory SBIR Phase II program that expanded the system for larger military uncrewed aircraft operating in more complex airspace.

The current OCAST-funded project extends that work by adapting the technology for broader commercial use. Vigilant Aerospace said the resulting product family is intended to support both smaller commercial drones operating in cooperative airspace and larger platforms requiring radar-based detection of non-cooperative traffic.