Automatic Ground Collision Avoidance and Loss of Control Prevention Systems for General Aviation using Run-time Assurance

Flight safety has been a fundamental objective for all of aviation for decades with a variety of enhancement measures being undertaken globally to mitigate aviation risks. Aircraft terrain collision results in a majority of the fatalities and serious injuries for general aviation aircraft accidents contributing to its high risk. Terrain collision can be further decomposed into two major categories leading to the event: controllable terrain collision and uncontrollable terrain collision. In controllable terrain collision, which are often classified as Controlled Flight Into Terrain (CFIT), the aircraft has functional control surfaces with a sufficient degree of control authority to maneuver, however, loss of situational awareness leads to terrain collision. In uncontrollable terrain collision, typically classified as Loss of Control Inflight (LOC-I), a poor energy state coupled with loss of aerodynamic control and lift, leads to terrain collision. Both CFIT and LOC-I are the two leading factors for total losses and number of fatalities in general aviation aircraft incidents. This paper proposes a unique framework utilizing a run-time assurance (RTA) architecture to successfully prevent both CFIT and LOC-I during concurrent and conflicting activation in general aviation aircraft. This research focuses on the systematic analyses of design selections and impacts on the safety and accuracy of a combined Automatic Ground Collision Avoidance System (Auto GCAS) and Automatic Loss of Control Prevention (Auto LOCP) system for a fixed-wing general aviation aircraft performed in a real-time six degree of freedom (6DoF) flight simulation using a Cessna 172 aircraft model.