Product
STERNA Hybrid Pack for UAV
Promise
You're looking to hybridize your UAV, you’re at the right place
Learn more
(Our offer)
STERNA Hybrid Pack
for UAV
STERNA Hybrid Pack for UAVs has been specifically designed to address drones’ needs from small UAVs (c. 25kg MTOW) up to several-tons UAVs (such as heavy cargo UAV able to carry several hundreds of payload).
Compared to full-electric UAVs:
up to 4x endurance and range, enhanced availability rate (thanks to battery in-flight recharge), ability to perform stationary flights during the mission (for VTOL UAV)
Compared to gas-powered UAVs:
stealth (reduction of acoustic and thermal signatures), enhanced availability rate, improved range & endurance, etc.
Small UAV
Light tactical UAV
Cargo UAV
(our Services)
End-to-end hybrid propulsion solutions for your UAV products
Supply of Hybrid Pack to power your hybrid-electric development
Integration of complete hybrid propulsion system into your UAV
Want to know how this applies to your UAV?
(our Expertise)
Hybrid electric pioneers since the start, in 2018.
Built on true aircraft maker heritage
Hybrid Architecture Expertise
Optimized weight, seamless fit
(Applications)
Hybridization Gains
Hybrid-electric propulsion system to power your UAV and enhance their performance
Range & Endurance
Up to x4 compared to full-electric UAV.
Stealth
Reduction of acoustic & thermal signatures compared to gas-powered UAV.
Applications
Ability to have full-electric flight phases depending on mission requirements.
Agility
Turnaround time divided by ~2 compared to full-electric UAV.
Weight Reduction
Weight optimization & payload capability increase.
Hovering Capability
For VTOL UAV, ability to perform several hovering phases depending on mission requirements.
Fast Integration
No need to modify existing BMS, as it comes natively with its own energy management system.
Hybrid-electric propulsion system to power your UAV and enhance their performance
Range & Endurance
Up to x4 compared to full-electric UAV.
Stealth
Reduction of acoustic & thermal signatures compared to gas-powered UAV.
Applications
Ability to have full-electric flight phases depending on mission requirements.
Agility
Turnaround time divided by ~2 compared to full-electric UAV.
Weight Reduction
Weight optimization & payload capability increase.
Hovering Capability
For VTOL UAV, ability to perform several hovering phases depending on mission requirements.
Fast Integration
No need to modify existing BMS, as it comes natively with its own energy management system.
Hybrid-electric propulsion system to power your UAV and enhance their performance
Range & Endurance
Up to x4 compared to full-electric UAV.
Stealth
Reduction of acoustic & thermal signatures compared to gas-powered UAV.
Applications
Ability to have full-electric flight phases depending on mission requirements.
Agility
Turnaround time divided by ~2 compared to full-electric UAV.
Weight Reduction
Weight optimization & payload capability increase.
Hovering Capability
For VTOL UAV, ability to perform several hovering phases depending on mission requirements.
Fast Integration
No need to modify existing BMS, as it comes natively with its own energy management system.
(Our technology)
Hybrid electric propulsion
system
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.
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 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.
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.
Scalable
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.
(our clients)
They chose our products
.jpg)
Company
Jean-Baptiste Djebbari Joins Ascendance’s Strategic Committee
Jean-Baptiste Djebbari, former Minister of Transport, is joining our strategic committee
Technical progress
On the route to permit to fly
Ascendance was welcoming EASA for the 3rd time this year
Company
Ascendance has been ranked in the Top 100 of TIME's World’s Top GreenTech Companies of 2025!
Proud to be recognized among the world's top greentech companies! 🌍🌱
You have some questions?
We have answers
STERNA Hybrid Pack is the combination of 3 core components: a novel battery pack co-developed with our partner Exoes and natively designed for hybridization in aviation, a Hybrid Energy Management System (HEMS) who is the “brain” of the system and automatically manage the energy, and a Hybrid Core Unit (HCU) who connects together the engine and battery in a safe & certifiable manner.
More endurance, more range (up to x4 compared to full-electric UAVs), new functionalities such as ability to do stationary flights and reduced turnaround time (thanks to in-flight charging capability), or to switch to full-electric flight if required. Improved stealth (acoustic and thermal signatures reduction) compared to gas-powered UAV
We have different product families of STERNA Hybrid Pack for UAV, and can equip the most relevant Hybrid Pack version on either UAV of 25 kg MTOW (small tactical UAV), light tactical UAV (from 50 to 150 kg MTOW), or larger UAV such as heavy cargo UAV (c. 300 kg payload) or MALE UAV (several tons of MTOW).
Yes. Our STERNA Hybrid Pack is optimized and designed as a whole to offer the best performance when equipped on a UAV, but we can provide parts of this Hybrid Pack if it fits your specific requirements.