Defining Well Clear for Unmanned Aircraft Systems

A key challenge associated with integration of Unmanned Aircraft Systems (UAS) is developing a means to sense and avoid (SAA) other aircraft. One of the main functions of SAA is to remain “well clear” of other aircraft. While human pilots determine “well clear” subjectively, SAA systems need a clear quantitative definition of UAS Well Clear. The Sense and Avoid Science and Research Panel (SARP) brought together key experts, determined guiding principles for UAS Well Clear, and aligned research efforts from NASA, Massachusetts Institute of Technology (MIT) Lincoln Laboratory, and the U.S. Air Force Research Laboratory to evaluate three UAS Well Clear candidates in four modelling and simulation environments. The three Well Clear candidates were evaluated against eight agreed evaluation metrics. The result of the SARP evaluation process led to a recommended quantitative definition for UAS Well Clear, promising to close one of the most urgent research gaps for UAS SAA.