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Practical Issues in Contingency Planning for UAVs with Engine Failures

Unmanned Air Vehicles (UAV), also known as Unmanned Air Systems (UAS), are gaining more attention in recent years. Some potential commercial applications with UAVs may include small cargo transport, search and rescue operations, drought and pest monitoring, etc. It is well-known that UAVs are less reliable as compared to manned aircraft. This is probably one of the consequential reasons that Federal Aviation Administration (FAA) is hesitant to open up the national airspace (NAS) and imposes tight restrictions to UAVs. Reliability of UAVs can be improved using engines and equipment with high quality and fault diagnostic algorithms using machine learning and artificial intelligence techniques, and robust and fault tolerant controllers. Despite the above measures, engine and equipment malfunctions may still appear in various applications. In this paper, we summarize some recent research results by us with respect to engine failures encountered in UAVs. Due to engine failure, there is limited hanging time and the mishap UAV needs to land preferably in an unpopulated area. In particular, we explicitly address some practical issues related to engine failures.