Handling Ground Risks for Road Networks in UAS Specific Operations Risk Assessment (SORA)

This paper proposes a modification to the Specific Operations Risk Assessment (SORA) process to explicitly account for risks wrt. vehicles on road networks, in addition to risks wrt. people, in the determination of a Ground Risk Class for the UAS operation. The definition of a new risk index, the Road Risk Class (RRC), is proposed and expressions for its computation are given. Following the methodology of the actual SORA, these expressions are used to pre-compute a numeric table helping in the determination of the RRC from the UAS characteristics and road traffic data. The proposed risk assessment process is illustrated on an example of long-range mission with a fixed-wing UAV.