Electric evolution: VoltAero unveils latest Cassio 330 production configuration
June 15, 2025
As exhibitors made the final finishing touches to their stands for this year’s Paris Air Show on Sunday afternoon, French developer, VoltAero, showcased the latest production configuration of its five-seat Cassio 330 hybrid-electric aircraft.
The developer’s updated design, which offers a more conventional configuration, abandons the earlier twin-boom tail and single pusher propeller layout, which was showcased at Paris two years ago. Instead, a pusher electric motor is installed on each side of the aft fuselage (a design inspired by the E-Fan which featured two ducted fans mounted on the fuselage sides) while a thermal engine inside the aircraft serves as a range extender by recharging the onboard batteries positioned either side of the fuselage.
In addition the twin-booms and high-set horizontal tail featured in the original design have been replaced with a more conventional T-tail.
Easing the way for EASA certification
Jean Botti, VoltAero’s CEO and CTO explained that multiple factors led to this design evolution, including CS23 certification discussions with the European Union Aviation Safety Agency (EASA).
“It’s been a long journey since we started out in 2021, but anything we can do to minimise any risks is key,” said Botti, as he explained that the new more conventional configuration, which features a thermal engined powered by an auxiliary power unit (APU), is expected to ease the EASA certification process. Once the aircraft’s architecture and aerodynamics are validated, Botti added the hybrid powertrain can be introduced.
Central to the aircraft’s fully redundant propulsion architecture is the use of two Safran ENGINeUS smart electric motors, mounted on the aft-fuselage and placing the Cassio 330 in the multi-engine aircraft category.
Further contributing to this built-in redundancy are two separate and independent battery strings, each paired with one of the ENGINeUS motors, ensuring continued performance.
While VoltAero had originally planned to build a parallel-hybrid powertrain using a four cylinder 150kW Kawasaki engine, the redesigned series hybrid powertrain means a more powerful thermal engine is required. Botti said a six cylinder Kawasaki engine is being considered, but is not confirmed.
He did however confirm that “flight testing of the first Cassio prototype, most likely featuring two certified thermal Rotax 916 engines, is planned for early 2026.” Certification, he added, is planned for late 2027.”
A full-size mock-up of the new Cassio 330 is on display on VoltAero’s stand at the show.
Targeted customers
Primarily targeting the U.S. market, the Cassio 330 is intended for private owners, regional charter operators, air taxi services, and small cargo operations, as well as medical evacuations. The interior layout can accommodate a pilot and up to five travellers in a spacious cabin. A large door forward of the wing facilitates access for passengers with reduced mobility, ensuring easy, inclusive access.
Building on the Cassio 330, VoltAero already has a larger 12-seat version, the Cassio 600, as well as the six-seat Cassio 480 in development, both of which will incorporate pure hybrid architecture.
Hybrid power unit
VoltAero is also showcasing its hybrid power unit (HPU) 210 power train, which it launched earlier this month. The powertrain is designed to deliver hybrid-electric propulsion for homebuilt and kit-built aircraft.
“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 Botti.
The HPU 21- will be supplied as a turnkey solution with the kit including a complete powertrain unit composed of the thermal engine, electric motor, gearbox and electronic control unit.
