A third set of tests at NASA’s Armstrong Flight Research Center to develop detect-and-avoid (DAA) technology for unmanned aerial systems (UAS) has delivered promising results, the agency reported Wednesday.

Working with industry partners General Atomics Aeronautical Systems Inc. and Honeywell International Inc., NASA flew the Ikhana UAS—a civilian research version of the General Atomics Predator B—with a prototype system of DAA sensors in concert with airborne and ground-based computers.

General Atomics developed one of the three primary DAA sensors flown on Ikhana which included a prototype radar system. It also contributed the Ikhana system and self-separation and collision avoidance alerting logic software.

The other two sensors included an Automatic Dependent Surveillance – Broadcast (ADS-B) from BAE Systems, and a second-generation Traffic alert and Collision Avoidance System (TCAS) from Honeywell.

Honeywell also provided software that enabled the three sensors to work together, as well as a specially instrumented aircraft to play the role of an intruder encroaching on the Ikhana’s airspace.

During the third in a series of flight test campaigns for NASA’s Unmanned Aircraft Systems Integration in the National Airspace System (UAS-NAS) project, the Ikhana made 11 flights involving more than 200 scripted encounters with approaching aircraft.

“We recorded some valuable data that will take some time to analyze fully, and we expect we’ll need to make some minor refinements to our algorithms,” said Dennis Hines, director for programs at the at the flight research center near Edwards, California. “But from what we saw during the tests, the results look promising.”

Depending on the specific scenario, the Ikhana either detected one or more approaching aircraft and sent an alert to its remote pilot to take action or the Ikhana itself took action on its own by flying a programmed maneuver to avoid a collision—an aviation first, according to NASA.

“The successful completion of this flight test campaign represents the maturity of our detect-and-avoid system,” said Frank Pace, General Atomics president of aircraft systems.

“This phase of flight tests, and our ability to meet the challenge of integrating UAS into the NAS, wouldn’t be possible without the strong partnership that exists between NASA and its aeronautical industry partners,” Hines said.

Information from the data recorded during this phase of UAS-NAS flight tests will help researchers plan the next tests expected to take place in spring 2016 and help organizations developing UAS-related operating standards.