Collision Avoidance for Unmanned Aircraft: Proving the Safety Case

Abstract

The MITRE Corporation and Lincoln Laboratory have collaborated on this paper because we believe that it is important to articulate the system safety studies needed. Our two organizations bring a wealth of knowledge and experience associated with the development and implementation of TCAS. We were directly involved and/or closely associated with a significant portion of the system safety analysis that supported RTCA, FAA, Eurocontrol, and International Civil Aviation Organization (ICAO) decisions related to TCAS2 standards and certification. Section 2 of this paper describes the safety analysis process. It gives a high level description of each step in the process, with emphasis on issues unique to UAS. Sections 3 through 5 describe selected areas in more detail. Section 3 addresses sensors and algorithms, which are specific aspects of the Concept of Operations. Section 4 describes encounter model development. Sections 5 describes the combination of fault tree analysis and dynamic simulation to assess UAS collision avoidance performance. Section 6 gives a summary.