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Our unique hybrid-electric propulsion technology.

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(Power up to)

1 MW

(Fuel savings up to)


(CO2 emissions up to)



Unique technology for more sustainable aviation

Sterna is a modular, scalable system that combines two energy sources to progressively reduce aircraft emissions and achieve in-flight Net Zero.

a man working on a propeller in a factory

A cost-effective system based on the use of sustainable aviation fuel now, with a switch to hydrogen (burned or in fuel cells) as soon as the technology is ready and certified.

(Our technology)

Hybrid electric propulsion

A modular and scalable combination of two sources of energy (fuel + battery).

A hybrid-electric aircraft uses a mix of two energy sources: electric batteries, used during take-off and climb, to benefit from the instantaneous release of optimized, high-power engines that can run on Jet-A1, and sustainable aviation fuel or hydrogen tomorrow, for low-energy phases of flight, such as cruise.

Conventional aircraft

Aircraft equiped with Sterna


A conventional aircraft engine is usually sized for take-off and climb thrust requirements. This leads to an oversized engine for cruise flight, where most of the fuel is burned. Thanks to Sterna, we can decouple these 2 phases and optimize them to reduce overall fuel consumption over the entire flight.


During take-off and climb, the battery is used to provide high power for short periods. Thus, the powertrain does not need to provide the power during this phase, and take-off and climb rating can be removed and/or the powertrain downsized.


During cruising, the powertrain is used at maximum efficiency, as it is now specifically sized to achieve this level of performance.

a black and white photo of a propeller on a tripod
electric boost

Where innovation
takes flight

What does Sterna look like in an airplane?

Sterna is a set of technologies and components for aircraft and rotorcraft OEMs to make them more sustainable, whether for new developments or retrofitting existing aircraft with an STC*. Sterna can take several shapes depending on your aircraft and the program objectives, from turboprops to regional planes.



Hybrid-electric with minimal modifications to the existing airframe.







Go further in the de-coupling between Cruise and Take-Off/Climb to optimize the aircraft




*Patented AFT technologies:

Hybrid Operating System
Energy management system - handles the energy split in the system

Hybrid Core
Electrical power box - connects all components together safely & distributes the energy in the system

We’re taking aviation
to new heights.

(our Commitment)

Unlock today's and tomorrow's viable solutions for cleaner aviation. We provide the technologies and technical support to empower aircraft manufacturers to reduce the environmental impact of future generations of aircraft.

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Embedded intelligence

From energy management to flight controls, including a complete set of data from engines, batteries, etc., the hybrid propulsion system simplifies maintenance operations and improves aircraft availability and customer service.

Range & endurance

The combination of different energy sources and top-grade energy management algorithms ensure optimal performance in flight (cruise time and speed) and on the ground. Our technology adapts to existing infrastructures and limits turn-around times.

Energy transition

Our modular architecture can be adapted to new generation aircraft with a wide array of energy sources, from kerosene and biofuels to synthetic fuels and hydrogen fuel cells.

Safe & efficient

Our hybrid propulsion system is engineered to match the requirements of future distributed propulsion systems, and embeds the required algorithms to control the multiplied number of propellers to ensure safe, efficient flight.

Fly clean

Our hybrid propulsion system significantly reduces carbon and noise emissions, for cleaner skies today and tomorrow. Sterna is the key technology and cornerstone of cleaner aviation.


The complete hybrid propulsion system architecture can be scaled up to meet the future requirements of regional aviation, from 6-10 PAX up to 70 with current technologies, propelling aviation into a new sustainable era.

Inflight insights

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Advanced Air Mobility

Jean-Christophe Lambert's Groundbreaking Article about Hybrid Propulsion for VTOLs in "Réalités Industrielles"

Jean-Christophe Lambert Writes a Great and Complete Article about Hybrid Propulsion for VTOLs in te Latest Issue of "Réalités Industrielles"

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StartAir Club by GIFAS Establishes Inaugural Board with CEO Jean-Christophe Lambert Appointed as President

StartAir Club by GIFAS Appoints New Leadership to Drive Innovation in French Aerospace Industry

Read more

Sustainable aviation

The Mysteries of Aviation Batteries: Discover our New Video Series!

We Unveil 'Did You Know About?' Video Series, Starting with Aviation Batteries

Read more

You have some questions?

We have answers

We are the best to help you in that thanks to our “aircraft-maker DNA”. We can help you from Engineering to tests and ultimately working with you on the supply and assembly of the entire propulsion system based on our patented technologies such as HOS, our expertise in designing hybrid-electric propulsion system and our partners for other propulsion components. We are also developing a new aircraft, an eVTOL one, we know the constraints at aircraft level and we know how we should optimize at aircraft scale.

We will tailor our patented HOS technology to your aircraft specifications. Thus lowering the global program development risk thanks to the use of our already tested and proven technology. Once the aircraft is certified, we will also provide upgrades and in-service support.

As explained before in the first question, we can help you develop this STC thanks to our expertise.

Sterna can address aircraft ranging from turboprop commuter aircraft up to regional aviation.

During the preliminary sizing phases we support you in defining the optimal hybrid architecture for your aircraft and maximize integration gains in the aircraft. We have built a test capability up to 1MW to help our customers design their future generation of more sustainable aircraft.