Munich Company Achieves “Decisive Milestone” in Electric Aircraft Revolution
Munich, Bavaria, Germany – MTU Aero Engines, a leading German aircraft engine manufacturer, has announced a significant step forward in its ambitious project to revolutionize air travel with electric propulsion. The company successfully tested the hydrogen and air supply systems for its Flying Fuel Cell (FFC) technology, bringing emission-free regional flights closer to reality. This achievement is described by the company as a “decisive milestone” in the development of hydrogen fuel cell aircraft.
How the Flying Fuel Cell Works
The FFC system operates on a simple yet powerful principle: hydrogen flows in from one side, and oxygen from the ambient air enters from the other. Inside the fuel cell, electricity is generated to power an electric motor, which in turn drives the propeller via a gearbox. Crucially, this propulsion system emits neither carbon dioxide, nitrogen oxides, nor soot particles. Instead, its primary emission is water, making it an exceptionally clean alternative to conventional jet engines.
Successful Tests and Next Steps
MTU Aero Engines has now successfully completed the initial phase of testing the hydrogen and air supply components. The company is currently preparing the first integrated demonstrators, which will mark a pivotal phase in the project. For the first time, fuel cells, hydrogen systems, air supply, cooling, control mechanisms, and the electric motor will operate together under conditions simulating actual flight. This comprehensive testing aims to validate the system’s performance and safety.
In the fuel cell, hydrogen molecules are separated at an electrode into positively charged particles and electrons. These electrons then travel through a circuit, providing the electrical energy for propulsion. The hydrogen particles pass through a membrane to a second electrode, where they combine with oxygen and the returning electrons to form water. Heat is also generated as a byproduct of this process.
Since a single fuel cell produces only a low voltage, MTU stacks hundreds of these cells to create what are known as “stacks.” The first near-production stack, designed to deliver 350 kilowatts of power, is currently being built in Munich. Concurrently, the company is constructing a demonstrator for the entire system, anticipating the commencement of initial test campaigns later this year, in 2026.
High Efficiency and Reduced Noise
To facilitate extensive testing, MTU is commissioning two fuel cell test stands. One facility will analyze individual stacks with outputs exceeding 500 kilowatts, while the second will evaluate the complete powertrain. This rigorous testing environment will ensure that all components can react within seconds to changes in power demand, requiring immediate adjustments in hydrogen and oxygen supply to the fuel cell, as well as efficient heat dissipation from the cooling system.
According to MTU, the accompanying electric motor weighs approximately 40 kilograms and provides a continuous output of 600 kilowatts, boasting an efficiency of over 96 percent. This motor is designed to drive the propeller without the need for complex additional inverters. While the propeller remains the primary source of noise, the FFC system is expected to significantly reduce overall aircraft noise compared to current turboprop engines.
Future Applications and Partnerships
For larger regional aircraft, a single stack will not suffice. To address this, MTU is collaborating with several partners on the European research project HEROPS to develop a system with 1.8 megawatts of power. This modular technology is planned to scale up to two to four megawatts in the future. Such an electric hydrogen propulsion system could be deployed on shorter regional routes as early as 2035, with subsequent generations capable of handling short and medium-haul flights.
MTU and Airbus have recently announced a joint venture to bring this development to market. In early July, the two companies revealed their plans to establish a joint entity focused on the development, testing, production, certification, and customer support of fuel cell propulsion systems. Stefan Weber, MTU’s Chief Development Officer, hailed this collaboration as a “decisive milestone” on the path to the first hydrogen propulsion system and a demonstration of “true European technological leadership.”
Regulatory Challenges and Parallel Development
Despite the rapid technological advancements, a suitable regulatory framework for hydrogen-powered aircraft is yet to be established. Existing certification regulations were primarily designed for kerosene-burning engines, and an aircraft utilizing liquid hydrogen, fuel cells, and electric propeller propulsion presents unique requirements. These include secure tanks, pipelines, ventilation systems, and protection concepts for potential leaks.
To address this, MTU has been working closely with the European Union Aviation Safety Agency (EASA) since 2021. Their innovation agreement was extended in February 2026, ensuring that technical development and regulatory guidelines progress in parallel. Only when the complete system demonstrates its performance and safety under realistic conditions can the Munich demonstrator be transformed into a propulsion system for passenger aircraft.
