November 3, 2025
As part of the Etna project, supported by France 2030, Viraj Aero announces the successful completion of a ground test campaign on a gas turbine fully adapted to operate with pure gaseous hydrogen. The tests were carried out at the H2Pulse facilities, located on the Francazal airfield in southern Toulouse.
This technological milestone demonstrates the feasibility of a modular retrofit approach, enabling existing propulsion architectures to be converted to hydrogen without a complete redesign of the engine. The turbine was equipped with injectors specifically developed by Viraj Aero, designed to meet the unique challenges of hydrogen combustion. All test sequences, ignition, ramp-up, steady-state operation, and shutdown, were successfully completed under 100% hydrogen fuel.
This achievement places Viraj Aero among the very few teams, both nationally and internationally, to have operated a fully hydrogen-retrofitted turbine.
Beyond this technical success, the campaign marks a new step in Viraj Aero’s development trajectory, as the company advances its work on steam injection systems for aeronautical turbines. These systems are designed to offer a solution compatible with conventional fuels, sustainable fuels, and, ultimately, hydrogen.
Our technology, based on the principle of steam injection, is initially developed to improve the efficiency of engines running on conventional fuels. But this principle shows even greater potential with hydrogen, which produces about 2.5 times more water than kerosene during combustion. That’s why we’re preparing this transition today, so that we’ll be ready when the market and infrastructures are in place,” said Joseph Risson, President of Viraj Aero.
The same prototype had already undergone steam and water droplet injection tests last year, validating the thermodynamic performance gains associated with the concept developed by the company.
Viraj Aero extends its gratitude to BPI France, ISAE-Supaero and H2Pulse for their valuable contribution to the project.
