Safely Flying BVLOS in the EU with an Unreliable UAS

Safe autonomous Beyond Visual Line of Sight (BVLOS) flight is critical for the widespread exploitation of Unmanned Aerial Systems (UASs). Satisfying safety legislation requires documenting compliance with a raft of substantial requirements, a step which very few commercially available UASs have yet taken. Assessments under BVLOS conditions are required - but illegal for unassessed UASs. We propose to enable safe BVLOS flight tests using an Independent Failsafe System (IFS), which can be added to an Unmanned Aerial Vehicle (UAV) and enable a pilot to remotely monitor flights and terminate them safely via parachute if necessary. Our IFS has been designed for use under the European Union (EU) UAS legislation. In this paper, we describe this IFS and define a systematic approach for integrating its use into the Specific Operations Risk Assessment (SORA) process necessary for BVLOS certification. The use of this IFS to safely fly an (otherwise) unsafe UAV has been approved by the Danish Civilian Aviation Authority (CAA) for BVLOS flights with a range of small multirotor UAVs. The results of experimental evaluations in closed airspace are presented.