Safety Considerations for a Distributed Electric Propulsion Aircraft: Lessons Learnt from an Automated Flight-Test Accident Involving a Research Demonstrator
Characterizing the highly complex aero-propulsive interaction in distributed electric propulsion (DEP) aircraft may require automated flight-testing procedures with dedicated maneuvers, which introduce specific safety challenges. This paper investigates an accident involving a distributed electric propulsion research demonstrator, named SwitchMaster, during an automated flight-test mission for aerodynamic model identification. The event occurred during a scheduled pitch excitation maneuver and resulted in a loss of control followed by ground impact. The investigation is based on flight logs, telemetry analysis, and structured accident investigation methods, including the ICAO ADREP taxonomy and the Swiss Cheese Model. The results show that the accident resulted from a combination of open-loop control surface fixation, insufficient real-time safety barriers, ineffective maneuver interruption, and delayed recovery authority. Variable wind speeds and asymmetric trim acquisition are considered possible contributing factors to the aircraft drift from equilibrium conditions. This paper concludes with safety recommendations, software improvements and lessons learnt to enhance the reliability of automated flight testing for DEP aircraft.
This paper outlines observations from an FAA-sponsored research project that examined aviation fly-by-wire (FBW) accidents in helicopters, transport-category airplanes, and powered-lift aircraft. The goal was to identify risk areas that will help guide a focus for FAA certification testing. Part of this study specifica...
Martin Shubert, David Sizoo, Michael Jones· Journal of the American Heli...· 0 citations
The National Transport Safety Board found that Wheels-Up Landing was the second highest defining event for aircraft accidents from 2008 to 2022. The increasing push for sustainable propulsion and accompanying novel airframe architectures present new integration and safety challenges for aircraft design and development,...
Jesse Wallace, D. Quinn, Declan C. Nolan et al.· Aerospace· 0 citations
Traditional aircraft rely on a combination of ailerons, elevators, rudders, and propulsion for flight control. However, a failure in the rudder can significantly compromise lateral-directional control and even be catastrophic, depending on flight phase and the aircraft dynamics. Recent advancements in hybrid-electric p...
Gabriel N. P. Silva, F. Cardoso-Ribeiro, Marco A. O. Alves· Journal of the Brazilian Soc...· 0 citations
Fixed-wing surveillance aircraft built around electric or small internal-combustion propulsion offer good endurance but are speed-limited, which restricts their ability to reposition rapidly over long standoff distances or evade emerging threats. This paper presents the design, integration methodology, and performance...
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This paper describes the first ever flight demonstration of a stability augmentation system using electromechanical inline actuators in a rotorcraft without hydraulic force amplification. A coaxial ultralight helicopter equipped with the stability augmentation system is used as a flight demonstrator. The paper covers...
B. Rothaupt, Walter Fichter, B. Grebing· CEAS Aeronautical Journal· 0 citations
This paper investigates the flight test method for the Minimum Control Speed during Approach and Landing (VMCL) dynamic test of a twin-engine narrow-body mainline airliner undergoing EASA type certification in accordance with CS- 25 requirements. The research identifies the core challenge as the significant energy stat...
