UK-based global major power and propulsion systems group Rolls-Royce on Monday reported that its new small gas turbine, intended to form part of a turbogenerator system that will be used to power hybrid-electric aircraft, was ready to start tests. This new gas turbine has been developed by Rolls-Royce Deutschland and will be tested, using sustainable aviation fuels (SAF), at its new test facility in Dahlewitz, near Berlin in Germany. The development of the engine has been partly funded by the German Federal Ministry for Economic Affairs and Climate Action.

“Rolls-Royce will be the leading provider of all-electric and hybrid-electric power and propulsion systems for Advanced Air Mobility,” said Rolls-Royce president: electrical Olaf Otto. “The Pass-to-Test of our brand-new small engine that will power our turbogenerator system is an important step forward. This product will enable our customers to extend the routes that electric flight can support and means more passengers will be able to travel further on low to net zero emissions aircraft.”

The turbogenerator system, of which the new gas turbine will form the heart, is aimed at powering a range of aircraft, from electric vertical take-off and landing urban air mobility aircraft (“flying taxis”) up to 19-seat commuter aircraft. The system will be able to provide scalable power outputs ranging from 500 kW to 1 200 kW. Using SAF, and (when it becomes available) hydrogen fuel, it will support operations on routes that are currently too long for all-electric (battery) powered aircraft to manage.

The new small engine has been developed using recent technological advances. Rolls-Royce reported that these have allowed it to achieve a “step change” in the efficiency of gas turbines of this size.

The development of the complete turbogenerator system brings together the group’s competencies in both gas turbines and electrical systems. The turbogenerator will be able to be used in parallel or serial hybrid applications. It is designed to be able to both recharge batteries and to directly power electrical propulsion units, and will allow aircraft to switch between power sources while in flight.

The group is developing complete all-electric and hybrid-electric power and propulsion systems. Those currently being designed will make use of leading-edge technologies, including those in the areas of power generation, electric motors, energy storage, and power electronics and control systems.