Aircraft

Cassio 1 aircraft successfully test-flies its hybrid drive system

Cassio 1 aircraft successfully...
Looking forward from the back of the Cassio 1 testbed aircraft
Looking forward from the back of the Cassio 1 testbed aircraft
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Along with providing propulsion, the Cassio's combustion engine also serves to charge the electric motors' batteries while in flight
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Along with providing propulsion, the Cassio's combustion engine also serves to charge the electric motors' batteries while in flight
One of the two ENGINeUS 45 electric motors
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One of the two ENGINeUS 45 electric motors
Looking forward from the back of the Cassio 1 testbed aircraft
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Looking forward from the back of the Cassio 1 testbed aircraft
VoltAero ultimately plans on manufacturing 4-, 6- and 9-seat versions of the Cassio
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VoltAero ultimately plans on manufacturing 4-, 6- and 9-seat versions of the Cassio
VoltAero's hybrid power module
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VoltAero's hybrid power module
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As is the case with electric cars, battery range is still very much an issue with pure-electric aircraft. Hybrid propeller-drive systems are perhaps a better way to go – for now – and a new one was recently the subject of a successful test flight.

The flight was conducted by French startup VoltAero, utilizing the company's Cassio 1 testbed aircraft at the Royan-Médis Aérodrome in France.

Two propellers were installed on the wings (one per wing), each prop being driven by a separate 60-kilowatt ENGINeUS 45 electric motor made by Safran Electrical & Power. A third pusher propeller, in the rear of the aircraft, was powered solely by a conventional 170-kW combustion engine.

Along with providing propulsion, the Cassio's combustion engine also serves to charge the electric motors' batteries while in flight
Along with providing propulsion, the Cassio's combustion engine also serves to charge the electric motors' batteries while in flight

However, in the final production version of the aircraft, VoltAero plans on swapping the stand-alone rear engine for a hybrid power module. That unit consists of three 60-kW electric motors combined with a single 300-kW combustion engine, for a total output of 480 kilowatts. The module has already been built, but is currently still undergoing ground-based testing.

According to test pilot and technical director Didier Esteyne, the ENGINeUS motors were found to produce no vibrations and "extremely low noise levels."

VoltAero ultimately plans on manufacturing 4-, 6- and 9-seat versions of the Cassio. Company president Jeffrey Lenorovitz tells us that the plane should have a top speed of 200 knots (370 km/h or 230 mph) and a flight endurance of at least 3.5 hours. Deliveries are expected to take place between 2021 and 2022.

Highlights from the test flight can be seen in the video below.

Source: VoltAero

VoltAero hybrid-electric flight testing with the Cassio 1 testbed aircraft

View gallery - 5 images
3 comments
CAVUMark
Excellent. Put me down for the first 4 place!
Steve Jones
Looks really nice. Are those black wings PV/solar? They could be, right?
Eggster
If I understand what I am seeing, then the forward facing props eliminate a great deal of drag because the electric motors only require an extremely slim cowling, while the rear facing, conventional IC motor doesn't impose any additional drag because its large cowling is integrated into the rear of fuselage.