Towards Handling Qualities and Automation Assessment for Certification of eVTOL Aircraft

Led by the Federal Aviation Administration (FAA), research is being conducted to develop certification means of compliance methods for small aircraft including the emerging class of advanced air mobility vehicles that will transition from thrust-borne flight to wing-borne flight and vice versa. These vehicles typically feature highly augmented fly-by-wire flight control systems that offer advanced flight control modes designed for simplified vehicle operations and in many cases completely autonomous flight operations. The emerging means of compliance methods will feature special classes of flight test maneuvers that address the assessments of the vehicle system, flying qualities, handling qualities, and increasing automation. Inspiration for this approach comes from the Army's Aeronautical Design Standard ADS-33-E-PRF that introduced a mission-oriented approach to address handling qualities via predictive requirements and specified flight test maneuvers - Mission Task Elements. Whereas ADS-33E-PRF prescribes methodologies through a procurement process, the FAA seeks a means to determine that a minimum safety standard has been met by an aircraft presented for certification. Thus, the flight test maneuvers as conceived here form a holistic approach to determine acceptable handling qualities via a process that encompasses the period between Type Certification (TC) application to the point where the TC is granted. To facilitate the process further, a team led by Systems Technology, Inc. (STI) is developing a flight test guide that will support the safe and repeatable execution of these flight test maneuvers. This paper provides an overview of not only the holistic approach to handling qualities assessments, but also the key elements of the flight test guide.