A Detect And Avoid concept for UAS operations near Hospital Emergency Medical Services helipads in uncontrolled urban airspace

This work presents a Detect And Avoid (DAA) concept which was used to enable drone healthcare logistics flight tests adjacent to a Hospital Emergency Medical Services (HEMS) helipad in Denmark.The flights tests were conducted in uncontrolled airspace above a city, where medical helicopters land on average 1-2 times a day.The DAA concept utilizes ground-based ADS-B and FLARM receivers to establish situational awareness of the adjacent airspace.The DAA concept together with an associated risk assessment was included in a Specific Operations Risk Assessment (SORA) based application, which received a flight authorization from the Danish Civilian Aviation Authority (CAA).During a 3 month period, a total of 354 flight tests were conducted totaling 69 hours in air.The operation was inspected by the Danish CAA who have expressed no concerns about the safety of the flight tests.