Ayşe Akalın: First of all, thank you for sparing time for our readers. Can we start our interview by taking a brief summary of your personal journey to the VoltAero after leaving Airbus in 2016?  

Jean Botti: First of all, Thanks to all you readers and I am happy to share my personal journey since the creation of VoltAero in September 2017.

We have been going through an incredible journey with the team. We went from 3 co-founders to more than 30 full time people today. We have created multi-national partnerships around the world and we have also created two beautiful and efficient aircrafts the demonstrator Cassio S who flew recently with a 100 % electric/Biofuel made of grapes waste, and the Cassio 330 the first of our future aircraft family

  Ayşe Akalın: How would you best describe VoltAero, which is headquartered at the Aérodrome de Royan-Médis in southwest France? 

Jean Botti: It is a spin off of the original Airbus team,that was working under my direction at the time when I established the Electric Roadmap for Airbus. We look like the movie the “expandables” ! Very happy to have a diversified team, mixing senior people with 80 years of expertise combined in electric aviation with very young new comers. 

 Ayşe Akalın: Could you please provide some key facts about the company for our readers? 

Jean Botti: Well here are some Key facts:

1. First to fly a 600Kw parallel Hybrid Aircraft in the world in 2020

2. Won the prestigious Award for best technology of the future at the German Aero Airshow in Germany in 2023

3. Just received the Janus price in France for best Design all categories included.

4. Labelled by Solar impulse foundation in September 2021

5. Elected as a partner by Air New Zealand in 2022

6. Price of best Engineer by the prestigious French industrial Magazine in 2021 

7. Selected by Netherlands to be a partner in the Power-Up consortium (major Dutch Airports) in order to develop the electric aviation for tomorrow

 Ayşe Akalın: Can you inform us about VoltAero’s current final assembly line at Rochefort Airport in France’s Nouvelle-Aquitaine region and its annual production capacity?

Jean Botti: On October 3rd we had the ground breaking of the production plant in Rochefort France. The plant will be ready in August 2023. Production of 150 Airplanes in steady state operations within the next 4 years.

 Ayşe Akalın: VoltAero has been developing an all-new airplane family, dubbed ‘Cassio’ and is claimed to set the standards for electric aircraft. Can you describe the Cassio electric-hybrid aircraft family with three sizes - the Cassio 330, 480 and 660, for our readers?

Jean Botti: VoltAero is taking electric aircraft to an entirely new level. Benefitting from 80-plus years of combined pioneering expertise, VoltAero is developing a truly unique general aviation airplane with electric-hybrid propulsion for safe, quiet, efficient and eco-friendly flight. VoltAero’s proprietary Cassio design is based on a sleek, aerodynamically-optimized fuselage, a forward fixed canard, and an aft-set wing with twin booms that support a high-set horizontal tail. Seating from five to 12 persons, Cassio will have a flight duration of at least 3.5 hours – providing a highly-capable and reliable 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 (cargo, postal delivery, Medevac) applications. It will be certified to Europe’s EASA CS23 certification specification as a single-engine, general aviation category aircraft, and is designed from the start for a low cost of ownership. 

Cassio will be offered in three versions, each sharing a high degree of modularity and commonality:

Cassio 330, a five-seat configuration with propulsion from a combined electric-hybrid power of 330 kilowatts;

Cassio 480, configured with six seats and an electric-hybrid propulsion power of 480 kilowatts;

Cassio 600, with a 10-12-seat capacity and electric-hybrid propulsion power of 600 kilowatts.

The VoltAero flight demonstrator, the Cassio 1 aircraft, is validating Cassio’s powertrain configuration, de-risking it for airworthiness certification.

 Ayşe Akalın: At Airbus, as Airbus’ Chief Technical Officer, you led the Electric Cri-Cri and E-Fan programs. To what extent were you able to transfer your electric aircraft experience from Airbus to VoltAero? Can we get an assessment of the reflections of the knowledge you gained from the years of working on E-Fan Project on the Cassio Project and the gains it has provided?

Jean Botti: It is clear that experience is crucial in this business. But I have to say that for the Cassio Family we came with all new ideas that in fact are even Patented. What we gained the most out of the past experiences was the possibility of scale up. In 2011 we flew the small electric acrobatic Cri-cri with 20Kw of power, then In 2015 we crossed the Channel in an historical flight with the E-fan, a 60 Kw power aircraft, still in pure electric mode.

In 2020 we flew the Cassio 1 demonstrator in Hybrid mode at 600 Kw power. We have multiplied by 30 the power on board in the last 12 years! 

Without the accumulated knowledge, it would have been very difficult to do.

Ayşe Akalın: The Cassio 330 electric-hybrid aircraft, that unveiled for the first time in June 2023 just before Paris Air Show is the first member of this family. Where do you see the strong points of Cassio 330 CTOL aircraft that features five seats and powered by the 330-kilowatt electric-hybrid propulsion system and how does it differ from its competitors? 

Jean Botti: Why the Cassio Hybrid is superior to a Full Electric propulsion system ?

• Hybrid allow a better batterie management which reduced the impact of current battery system limitations (stability, temperature management).

• Hybrid allow a better balance between range and battery weight (by an order of magnitude)

• Infrastructure readiness (hybrid aircraft are ground infrastructure agnostics). Not all airports will be equipped with electric chargers immediately. VoltAero with its Cassio Airplane will always be able to take off in any field

• Improves safety (dual source of energy that can be used independently or in combination)

• Better overall performance and operating cost, with a significant improved range compared to a full electric aircraft (800 NM or 1200Kms). By consequence, it is more suited for the regional aviation market.

• High level of recyclability (> 80%) thanks to the Aluminum airframe. The VoltAero Cassio Airplane has been conceived with this in mind. Contrary to composites that are very difficult to recycle. Eviation, Lilium, Joby and Pipistrel are composite made.

• Eviation, Joby, Lilium made the choice of of several propellers whereas VoltAero has selected a very specific unique propeller in order to minimize the noise an allow 24/7 operations

For all these reasons stated above VoltAero made the choice of the hybrid, half electric, half thermal.

The Cassio airplane – thanks to its modularity - possesses the building blocks that will enable it to include the future advancements in batteries, bio-fuels or hydrogen technologies. The research conducted in exclusive partnership with Kawasaki will allow us to quickly stay at the forefront, should hydrogen technology become reality.

Ayşe Akalın: Displayed for the first time during Paris Air Show 2023 the first prototype of Cassio 330 CTOL aircraft was announced to be used to validate the overall airframe configuration. When do you plan to perform first flight with Cassio 330 first prototype?

Jean Botti: We plan the first flight to happen second half of 2024 in order to open the flight domain and truly understand the Aerodynamics.

Ayşe Akalın: Can you elaborate on the parallel electric-hybrid propulsion concept utilized on Cassio Family? What makes it unique?

Jean Botti: Safe, efficient and eco-friendly: these are the keywords for VoltAero’s electric-hybrid powertrain.  

Equipped with VoltAero’s proprietary propulsion module – which combines electric motors and an internal combustion engine – Cassio aircraft will have propulsive power ranging from 330 to 600 kilowatts, corresponding to the aircraft’s versions with four, six and 10-seats. 

In its application on the mid-sized Cassio version – which has six seats – the hybrid power module combines 300-kW of internal combustion engine power with three electric motors of 60 kW each, delivering a total power of 480 kW. These multiple sources of energy ensure very safe modes of operation by utilizing one source of power (electrical or mechanical) – or both – depending on the usage scenario. In a typical flight, the electrical motors would be used for nearly-silent takeoffs and landings, with the internal combustion engine serving as a range extender. It is patented and we extend its validity to 62 countries

Cassio propulsion: key characteristics 

• Unique patented series/parallel hybrid design: from full electric to full rechargeable hybrid, depending on the flight profile and mission requirement 

• The dual source of power provides unmatched safety 

• 4 dBa lower noise than comparable aircraft during operations, and no noise during ground taxi (with an electrically-driven nose wheel) 

• 20% lower emissions than comparable aircraft in the full hybrid mode and 100% in full electric 

 Ayşe Akalın: Since 2020, VoltAero’s electric-hybrid propulsion system has undergone extensive airborne evaluations with the full-power 600-kilowatt version installed on the company’s Cassio 1 (a modified Cessna 337 Skymaster) demonstrator airplane, making it the world’s first parallel electric-hybrid powertrain to fly. Can you elaborate on the structural modifications performed on the Cessna 337 Skymaster airframe to convert it electric-hybrid airplane and testing/certification campaign carried out so far with the Cassio 1 demonstrator airplane? 

Jean Botti: Almost everything has been changed:

1. Batteries in the wings 

2. Two added electric motors support in the front of the wings

3. Completely new digital cockpit instead of the old analog one

4. Complete removal of the front and rear engines with replacement in the front nose of the engine by 3 battery packs and in the rear fuselage we installed our parallel hybrid power module

5. Total installation of 5 electric motors ( Safran and Emrax) and one thermal engine ( Nissan) for a total power of 600 Kw ( 300 Kw Thermal + 300 Kw electric)

Basically the only thing kept was the Aluminum structure, but we made significant modifications to it. 

The Demonstrator Cassio 1 is an experimental and will not be used for certification purpose.

Ayşe Akalın: What stage are you at with testing? How many flight hours have been accumulated with the Cassio 1? What is the most challenging aspect of the Cassio’s testing program? When do you expected to secure AESA certification for the Cassio Family of CTOL aircraft?

Jean Botti: For Cassio 1 we have now accumulated more than 215 flights and 157 flight hours 

We keep flying it in order to Test:

1. Bio-fuels

2. New low noise propeller

Everything is challenging for the Cassio 330 certification because this not a convetional Airplane and we need to make sure that EASA and later FAA will be comfortable with our approach. We hope for Type certificate by 2025

Ayşe Akalın: The second Cassio 330 prototype is expected to have its maiden flight in the second quarter of next year and expected to be used for the airworthiness certification program. Will there be any difference between the first and second prototypes in terms of propulsion system and cockpit layout?

Jean Botti: Yes there will be. The first aircraft is only validation the flight domain of the new aerodynamic design and the newly developed propeller.It will fly on thermal mode only and it will not be part of the official certification program

The second aircraft will be fully hybrid and will be integral part of the certification process.

Thanks to this approach it is better to validate step by step the technology bricks of our Cassio 330.

Ayşe Akalın: What can you tell us about the target markets and applications (such as air taxi/charter companies, private owners, postal delivery and medical evacuation) you foresee for the Cassio family? 

Jean Botti: We see a mix of applications and this is a huge market of more than 22 billion/year  for the General Aviation. We would be happy to take 10% of this market with our new technology.

Ayşe Akalın: When do you plan to start delivery of electric-hybrid Cassio aircraft to customers?

Jean Botti: By second half of 2025

 Ayşe Akalın: When will people first use an electric-hybrid Cassio Family aircraft? 

Jean Botti: End of 2025

 Ayşe Akalın: As VoltAero, how many sales figures do you predict for the Cassio Family?

Jean Botti:We want to have in steady state 150 Aircrafts per year to be built.

 Ayşe Akalın: Do you think there is a race to develop electric aircraft?

Jean Botti: When there is new technology, there is always a race to bring it to market. The first to market are the ones that can better conquest the market. It is true in every industry.

Ayşe Akalın: What other projects do you think are close to Cassio in terms of progress in the global electric-hybrid eVTOL aircraft market?

Jean Botti: They are many projects of electric aviation in the world,the list is too long, but a very few that really fly and have more than 3 years of true flying tests real scale as we do.

Ayşe Akalın: Does Cassio Family electric-hybrid eVTOL Aircraft Project is a company funded Project? 

Jean Botti: First of all we are not an EVTOL company, we are a fixed wing Electric Hybrid aircraft mainly a CTOL.

 Ayşe Akalın: How did you solve the funding issue? 

Jean Botti: Funding issue is nether solved, you always need funds to pursue your industrialization! Seriously, we have been raising funds both from public and private sectors so far. Now we are looking at raising even more private funds.

Ayşe Akalın: Can you elaborate on the strategic investors and industrial partners of the Cassio Family?

Jean Botti: We have two main industrial investors : Kawasaki in Japan and Tesi in Italy. We are discussing with others. They are very strategic for us in order to support the construction and certification of our first Cassio 330 Aircraft. Other partners like Safran, Avidyne, EPS , Aeroport de Paris, Electricity of France and Total Energies are very key for the Aircraft but also for the entire infrastructure.

 Ayşe Akalın: Do you believe that biofuels/sustainable aviation fuels will have an important role to play in aviation?

Jean Botti: I would like to believe so.They will be key IF their cost will become competitive in the near future .It is not the case today.

Ayşe Akalın: Would you like to add anything in the way of a message for our readers?

Jean Botti:In this business it is important to make the revolution by evolution, to say what you do and do what you and NOT to overcommit and under deliver. It goes for the credibility of the entire electric aviation industry reputation. We see too many fake news, just for the sake of attracting investors. The physics are true for everybody