A fuzzy-based site selection framework for emergency landings of commercial aircraft

Abstract

It is rare for a commercial passenger aircraft to be forced to carry out an emergency landing. Nevertheless, when such an event occurs, pilots are responsible for selecting a suitable landing site and flying the aircraft towards that site for a safe landing. This study addresses the challenges associated with the selection of the best emergency landing site – in a total loss of thrust scenario – by proposing a fuzzy logic framework which mimics the reasoning and decision-making process of airline pilots. The framework consists of a number of fuzzy logic systems which are used to quantify the risk associated with each landing site (conventional or unconventional) within the remaining gliding distance of the aircraft. The landing sites are then ranked in order of risk and presented to the crew. This risk assessment is not limited to the landing sites themselves, but also accounts for risks associated with the trajectories leading to those sites. Various aspects of the fuzzy logic framework – including the fuzzy variables, fuzzy sets, membership functions and fuzzy rules – were defined with the input of experienced commercial airline pilots and are discussed in this paper. The results of a preliminary evaluation of the proposed framework demonstrate its suitability for the intended scenario.