Formal Analysis of the Operational Concept for the Small Aircraft Transportation System

The Small Aircraft Transportation System (SATS) is a NASA project aimed at increasing access to small non-towered non-radar airports in the US. SATS is a radical new approach to air trafficmanagement where pilots flying instrument flight rules are responsible for separation without air traffic control services. In this paper, the SATS project serves as a case study of an operational air traffic concept that has been designed and analyzed primarily using formal techniques.TheSATS concept of operations is modeled using non-deterministic, asynchronous transition systems, which are then formally analyzed using state exploration techniques. The objective of the analysis is to show, in a mathematical framework, that the concept of operation complies with a set of safety requirements such as absence of dead-locks,maintaining aircraft separation, and robustness with respect to the occurrence of off-nominal events. The models also serve as design tools. Indeed, they were used to configure the nominal flight procedures and the geometry of the SATS airspace. Acronyms AMM Airport Management Module FAF Final Approach Fix HVO Higher Volume Operations IAF Initial Approach Fix IF Intermediate Fix IMC Instrument Meteorological Conditions MAHF Missed Approach Holding Fix PVS Prototype Verification System SATS Small Aircraft Transportation System SCA Self-Controlled Area