UAVOS Inc. and Stratodynamics Aviation Inc. have successfully completed the next stage of flights tests for their HiDRON stratospheric aircraft.

Reaching an altitude of 82,000 feet, the HiDRON carried an atmospheric measurement system onboard, as a result of a collaboration with researchers from the University of Kentucky.

The night-time flight, which was conducted in collaboration with the regional Air Traffic Control Agency, lasted four hours. There was a one-hour weather balloon launch period that had an average climb rate of 22 feet per second. At release altitude, the HiDRON was 22 miles away from the launch site where it headed home and was above launch area at an altitude of 59,000 feet.

Following this, the HiDRON glided near the home position with a descent rate much slower than a comparable parachute-born instrument. The return flight home lasted approximately three hours.

“This is the first time that this kind of atmospheric-sensing equipment has been integrated into a balloon-launched, unmanned glider and the results will enable the evolution of new UAV technology and in-situ observation methodologies,” says Travis Schuyler, a researcher from the University of Kentucky.

The mission team says that the HiDRON performed well in standard operational modes, as well as in challenging beyond visual line of sight (BVLOS) conditions. Operating in headwinds up to 112 miles per hour and in a temperature of -76 degrees Fahrenheit, the aircraft experienced wing icing, but still managed to return home, landing autonomously.

The main objectives of the mission were the HiDRON’s flight stabilization after balloon release and tuning the UAS controls and components for stratospheric flight. Operators also checked the performance of the HiDRON’s avionic systems, flight characteristics, safety features, instrument integration, and auxiliary tracking systems including a transponder during the flight.

The HiDRON’s payload collected meteorological data. The atmospheric instruments were integrated with the autopilot telemetry and the sensors were custom fitted to the aircraft. Data was collected at the ground station in real-time, and put together with the flight records.

Areas for further refinement were identified, but the team notes that the HiDRON and onboard measurement system performed well and demonstrated operability in high winds, cold temperatures, and low air density conditions. The performance data collected during the flight will be used for the next stage of testing, which will take place at an altitude of 98,000 feet.

“The HiDRON performed well in challenging winter winds and night conditions,” says Gary Pundsack, Stratodynamics Aviation Inc. founder and CEO. “The test demonstrated the HiDRON’s aerodynamic capabilities and avionic system reliability.”