High temperature brushless motor for driving jet liner engine actuator
23 December 2021
Electrification of Aircraft Systems for the Nacelle cowl NExt generation Opening System (NNEOS) project
Image reproduced from The UHBR engine flight testing programme gathers momentum | Clean Aviation (clean-aviation.eu)

First model of the actuator (reproduced from https://cordis.europa.eu/project/id/865197/reporting)
The Clean Sky Joint Undertaking is a public-private partnership between the European Commission and the European aeronautics industry that coordinates and funds research activities to deliver significantly quieter and more environmentally friendly aircraft. The Ultra High Bypass Ratio (UHBR) engine demonstrator, UltraFan® for large aircraft is being developed within this framework to help achieve these goals. In such an engine, the ratio of the air bypassing the core compared to the amount of air passing through the engine core is much higher (between 12 to 20 times) than it is in the best of today’s engines (at 10 to 12 times). This is projected to reduce fuel consumption by 15-17%. Such a design requires engines with much larger diameters, which in turn necessitates reconsideration of design of the pylon (the structure that connects the wing to the engines) and the nacelle (the engine housing).
The Nacelle cowl NExt generation Opening System (NNEOS) project is developing an electromechanical actuator to open and close the nacelle cowls and keep them open during maintenance tasks. This actuator development is being coordinated by Compañia Española de Sistemas Aeronáuticos (CESA), who are a part of Héroux-Devtek. The design of cowls moves towards a split concept, which divides the thrust reverser cowling system in two parts: external and internal cowls. The internal cowls bring new challenges to the cowl opening system, due to the highly constrained space allocation, high temperature and vibratory environment. Temperature constraints are a significant challenge in the development of the NNEOS equipment, having to withstand temperatures as high as 250 °C without degradation of system performance and durability. The available electric motors for such an application are unable to cope with such ambient conditions. This requires the design of a new motor to meet this and other requirements.
Dr Richard Strahan, a researcher at EPECentre UC has succeeded in Héroux-Devtek’s competitive tendering process for the design, build, and test a prototype brushless motor to meet the extreme operational requirements of the NNEOS. The project is expected to continue through to mid-2023.