gPC Methods for Validation of Future Air Traffic Management Concepts

The NASA Aeronautics Research Mission Directorate (ARMD) is supporting the development of a number of different concepts of airspace operations from trajectory based operations (TBO) to UAS traffic management (UTM) to urban air mobility (UAM). While these air traffic management concepts differ greatly in the details, the validation goal remains the same. To achieve safe operation, one must minimize flight risk. The current NAS relies on the cognition and decision-making capabilities of human actors to minimize flight risk. In order to realize the future air traffic management concepts described above, new validation strategies are required that can replace the safety assurances currently provided by the human actors in the system. The overall goal of the proposed research program is to develop a new validation strategy for future air traffic management concepts that is based on a probabilistic modeling methodology called generalized polynomial chaos (gPC). As measures of safety in aviation are inherently probabilistic, gPC provides a unique advantage over other methodologies that can isolate worst-case behavior but cannot necessarily quantify the likelihood of a hazardous/catastrophic event. During Phase I, Barron Associates will: (1) identify near-term, mid-term, and long-term air traffic management concepts, (2) define the operating space (e.g. variations in the airspace environment) and safety metrics for each concept, (3) compute a gPC model that maps the operating space for a given air traffic management concept to the set of metrics that characterize system safety, and (4) analyze the gPC model to quantify how the operating space impacts the safety metrics. While the Phase I program is structured to support a traditional validation process that occurs before fielding a new technology, Barron Associates will outline how the same techniques (with a few minor modifications) can be used to support In-Time System-wide Safety Assurance (ISSA).