After maintenance, turbofan engines are subjected to a performance acceptance test in an indoor test-cell to demonstrate that corrected performance thresholds are met. The same indicators are also monitored after on-wing installation. Despite corrections for operation conditions, differences are observed between test-cell and subsequent on-wing performance. A comprehensive list of potential root causes for those differences was investigated using data-driven analyzes, theory and simulations. The main root causes are thermal effects, resulting from the lack of thermal stabilization during on-wing operation, and seal run-in, resulting from the initial decrease of effectiveness of replaced seals. Aircraft sensor bias and test-cell correction factors are expected to also contribute considerably. Engine bleed air and power extraction effects are negligible. The impact of inaccurate or missing throttle, temperature and humidity corrections was eliminated by application of proposed engine-specific customized corrections, which served as a successful proof of concept for improved on-wing monitoring accuracy.

Following in the footsteps of the automotive industry with the successful implementation of Formula E, the E-SPARC design is the world’s first all-electric racing aircraft. E-SPARC’s mission is to proof the feasibility of a sustainable and high performance alternative for the current state-of-the-art in aerobatic racing. Thereby, the aim is to present a design worthy of competing in the popular Red Bull Air Races. Given the combination of being the world’s fastest growing international motorsport with the commitment towards reducing the carbon footprint [1], Red Bull Air Races provide the optimal platformfor the E-SPARC design. The leading design question is therefore whether an all-electric racing aircraft can be designed with performance characteristics equal to or exceeding the performance characteristics of the current competition. This report describes the design decisions and outcomes taken during the preliminary design phase, continuing upon the pusher canard configuration that was selected during the conceptual design phase...