High-Compression Engine (HCE) put to the test
The High-Compression Engine (HCE) designed for light helicopters first ran on a dedicated test bench as part of the HIPE AE 440 (Diesel powerpack for a light helicopter demonstrator) research project. The 440-shaft-horsepower demonstrator was planned to eventually power a modified Airbus H120 for flight tests. The HCE is a liquid-cooled, eight-cylinder, four-stroke piston engine fuelled with kerosene. The core engine was designed by a French company that specialises in racing car engines. Its partner in Austria focused on components like the full authority digital engine control and its airworthiness. The HCE has a total installed weight of ~ 250 kg. For an equivalent level of performance, a turboshaft would weigh ~130 kg. However, the HCE can retain its performance from sea level to 2 500 m and up to International Standard Atmosphere (ISA) temperature + 20, which a turboshaft cannot support. The developers of the HCE demonstrator – itself part of Clean Sky's Green Rotorcraft Integrated Technology Demonstrator – believed in the use of this kind of engine on a light helicopter. The reduced fuel consumption (up to -50 %) will enable to nearly double the range of the Helicopter for the same payload. After extensive trials of the test bench, HIPE AE 440 engineers assessed the way it interacts with the airframe in terms of vibration and validated its reliability. The HCE was powered up gradually to avoid unexpected failures and proved to meet performance expectations. Lastly, the HCE was integrated into a demonstration helicopter and the maiden flight was successfully performed in November 2015. During flight test, the HIPE AE 440 engine burned ~40 % less fuel than conventional turbine. Importantly, fuel savings resulted in substantially less exhaust and noise emissions.
Keywords
Diesel engine, aviation, light helicopters, HIPE AE 440, iron bird, turboshaft
