VoltAero has unveiled its production Cassio 330 hybrid electric aircraft at the Paris Air Show 2025, revealing a new look and revised, simplified technology. Aerotime explains the craft is a result of VoltAero working with the European Union Aviation Safety Agency (EASA) airworthiness certification agency.
Unveiled at 2025 Paris Air Show, the redesigned VoltAero Cassio 330 shows marked changes
The original twin-boom configuration has been replaced with a T-tail, and its original parallel-hybrid power train with an internal combustion (thermal) engine inside the fuselage and two aft-fuselage-mounted Safran ENGINeUS smart electric motors on each side of the fuselage under the T-tail. The internal combustion engine drives a generator that recharges the airplane’s onboard batteries in a serial hookup.
Changing to a single fuselage eliminates the potential of damage to the twin booms if a propeller blade fails. VoltAero explains, “The new configuration has a fully redundant architecture for operational safety. This begins with the two aft-fuselage-mounted Safran ENGINeUS smart electric motors, placing the Cassio 330 in the multi-engine aircraft category and opening its potential use in commercial air transport operations.”
Journalist Ian Molyneaux adds, “On June 15, 2025, the company said, ‘multiple factors led to this evolution” with a decision to “decrease complexity” in its ambitions for certification and “aligning its overall design in compliance with EASA’s latest CS.23 certification specifications for normal category planes’”.
Despite all the external changes, the 330’s interior layout stays the same, “accommodating the pilot and up to five passengers and retains the modularity for passenger transportation, cargo operations, and medical evacuation/air ambulance missions.”
Just before the Paris Air Show, Jean Botti, VoltAero’s CEO and Chief Technology Officer, reflects on the other things that remain unchanged. “As we take another step toward the Cassio 330’s production, our strategy remains unchanged: using safe and efficient electric-hybrid propulsion and power technologies that are realistically available today, applying them to a conventional takeoff/landing aircraft for sustainable regional transportation using existing airport infrastructure.”
Charlotte Bailey’s interview of Valenti Hardy, VoltAero’s sales and marketing manager, elicits the news that test flights of the 330 will start in late 2026, and that collaborative meetings with the EASA have eased the way toward type certifucaton of the airplane. Part of those talks, according to Flight Global’s Dominic Perry.
According to Perry, Jean Botti said design changes came about from certification discussions ith the EASA. The agency had concerns with guaranteeing the craft’s safetu if a propeller blade detached and hit a boom or the vertical tail of the previous design. Botti said, “It would have been very difficult to prove.”
The current, and the company insists, final design goes back to the E-Fan, which Botti oversaw during his time as Chief Technology Officer at Airbus. Swappng twin propellers for the E-Fan’s ducted fans, the powerplants are in exactly the same position on both craft. Botti says the two electric motors and their design, offer “a degree of redundancy not seen on the earlier iteration.” On the downside, the switch to a series hybrid powertrain won’t allow the aircraft to be powered only by the IC engine.
The thermal engine in the new craft will need to be more powerful than previous iterations because it will now have to act as a generator. The Safran motors will also need to be uprated, with the company obliging with units up to 180 kilwatts (241 horsepower). Jut to be on the safe side, the first test flights will probably find the aircraft powered by twin Rotax 916s. Botti explains, “It will be a good first test – it will allow us to completely explore the flight domain, do all the validation of the structure and make any changes we need. Once this is done, we can step to the hybrid.”
Cassio 330’s spacious interior remains much the same as in the twin-boom version, enabling cargo and medical missions
VoltAero showed a mockup of the new 330 at the Paris show, and performed with their Cessna 337 in the daily flying display.
Aviation Week reporter Graham Warwick was told the planned change from parallel to serial hybrid could be advantageous in new ways. Botti explained, “You lose that thermal redundancy, but at the same time you have more redundancy because you have one more motor and two separate battery strings. In addition, each motor is split in half because of the way the winding is done and that also creates redundancy.”
“Selecting this architecture—already well-known from the E-Fan 10 years ago—was for us the quickest way to get to a certified aircraft. It does not mean that for the larger Cassio 480 and Cassio 600 we would not go back to a pure hybrid architecture.”