VoltAero is entering the next phase of flight testing that will take its Cassio aircraft a closer to the full-up hybrid-electric configuration with a combined power of nearly 800 hp and top speeds of more than 200 kts.

For the upcoming phase of flight tests, the Cassio 1 testbed has been equipped using new-generation ENGINeUS smart electric motors from Safran Electrical & Power, along with new-design propellers. The electric motors are housed in purpose-built nacelles that have been integrated on the aircraft' testbed wings.

In the upcoming flight evaluations, the testbed aircraft will retain its original front and rear thermal engines, enabling the ENGINeUS 45 electric motors' functionality, along with the operation of the battery modules installed in the wings, to be evaluated with complete safety. This arrangement of the Cassio 1 testbed is designated the Version 2.2 configuration, which will be flown for approximately 20 hours.

When the Cassio 1 testbed's Version 2.2 configuration flight tests are completed, VoltAero will remove the aircraft's original rear thermal engine, replacing it with the other key element of the company's hybrid electric aircraft configuration: the proprietary hybrid power module.

At this point in the development, the flying testbed's original forward-mounted thermal engine also are to be removed, replaced by a smooth nose fairing containing additional electric batteries. The combination of two wing-mounted electric motors and the aft hybrid power module represents the propulsion configuration for the upper-end of VoltAero's Cassio aircraft product line, which will have from four to nine seats.

The power module, which incorporates three 60-kW high-performance electric motors and an internal combustion engine capable of producing 370 hp, is continuing its development on a ground test rig. This power module has two purposes: it serves as an electrical generator to recharge the Cassio aircraft's batteries and drives the rear-facing ‘pusher’ propeller.

When equipped in the full-up hybrid propulsion arrangement, comprising the two wing-mounted electric motors in the ‘pull’ position and the aft-facing hybrid power module with the propeller, the Cassio 1 testbed aircraft will be flown for more than 100 hours, including endurance and demonstration flights, validating the complete propulsion system for VoltAero's production Cassio aircraft.

Development and flight test activity for Cassio aircraft is being performed by VoltAero at its Aérodrome de Royan-Médis headquarters in the Nouvelle-Aquitaine region of France.

Production versions of Cassio aircraft will have a flight duration of at least 3.5 hours, with an extension possible to 5 hours. The aircraft will be marketed as a general aviation platform for private owners, air taxi/charter companies, commercial flights for point-to-point regional travel, and for use in other utility-category applications.