VoltAero launches HPU 210 powertrain
June 5, 2025
French hybrid-electric aviation pioneer VoltAero has introduced a new propulsion unit designed to bring its hybrid technology to light aviation.
The company revealed the HPU 210, a hybrid power unit aimed at the homebuilt, kit-built and very light aircraft segments, during its appearance at France Air Expo, held at Lyon Bron Airport from 5 to 7 June.
The HPU 210 marks VoltAero’s first move into the light aviation market, transferring technology developed for its Cassio regional aircraft to smaller, propeller-driven aircraft.
The system combines a 150 kW thermal engine with a 60 kW electric motor, delivering a combined boost function the company says can increase power by up to 40 percent during critical phases of flight, including takeoff and climb.
“With the HPU 210, a new category of airplanes will benefit from the patented, proven hybrid propulsion technology pioneered by VoltAero for our Cassio family of regional aircraft, which are now advancing into their pre-production phase,” said Jean Botti, VoltAero’s CEO & Chief Technology Officer.
“We’ve validated our hybrid propulsion architecture on our in-house Cassio S flying testbed, which has logged more than 185 flight hours and flown approximately 25,000 kilometres in a full range of operating conditions.”
At the heart of the HPU 210 is Kawasaki’s H2SX four-cylinder supercharged thermal engine, originally developed for the firm’s high-performance Ninja H2 SX sport motorcycle. Adapted for aviation, the engine delivers its output through electronic fuel injection and offers a projected time between overhaul (TBO) of 1,500 hours.
The powertrain’s electric component comes into play during high-demand scenarios such as takeoff, enabling improved obstacle clearance and enhanced cruise speeds.
Flight control is simplified through a single-throttle setup, where the thermal engine provides up to 70 percent of the output and the remaining thrust is automatically managed by the electric system.
VoltAero cites fuel efficiency figures of just 38 litres per hour during cruise, with compatibility across AVGAS, biofuels such as E85 and regular unleaded petrol, giving operators flexibility on both environmental impact and cost.
The HPU 210 has already undergone bench testing at VoltAero’s partner facility, AKIRA, in southern France. The complete propulsion package will be sold as a turnkey unit, comprising the engine, electric motor, reduction gearbox and electronic control systems.
Production of the HPU 210 will be carried out at VoltAero’s newly developed site at Rochefort Airport in Nouvelle-Aquitaine, the same facility that will produce the company’s Cassio aircraft range.
First customer deliveries of the HPU 210 are expected by the end of 2026.
