Tool for Quantitative Risk Assessment During UAS Approach and Departure

PI: Dr. Robert A. Canfield
Co-PIs: Tombo Jones and Robert Briggs (MAAP)

The U.S. Navy is interested in evaluating UAS safety targets and airworthiness standards that provide an acceptable level of safety to third parties on the ground. Manned aircraft airworthiness requirements, standards, and safety targets have been developed to minimize the likelihood of loss of life to persons on-board the aircraft in the event of a crash. With UAS, there are no aircrew or passengers on board, so the risk is shifted only to third parties on the ground. In civil airworthiness codes, FAA Advisory Circular AC 23-1309 and FAA AC 25-1309 provide safety targets for individual catastrophic failure conditions. These safety targets have been established based on civil aircraft mishap rates. These safety targets have been used by military airworthiness authorities to establish UAS safety targets with the aim of establishing airworthiness requirements that provide the minimum acceptable level of safety to third parties on the ground. NATO UAS Airworthiness Requirements contained in STANAGs 4671, 4702, and 4703 provide safety targets for military UAS. There are related efforts in Europe (EASA, JARUS) to identify methods and standards for safety targets for UAS (primarily those less than 55 lbs.). The major effort has focused on fully defining the quantitative risk assessment method of UAS approaching and departing a predefined area as well as scoping the level of effort required to develop a tool to implement the assessment.