Now, the decision to build a sustainable VTOL-Jet for civil aviation might come as a surprise to some, when it comes to the decarbonization of jet-aviation, as the J-27 Ignis will only cover a (not yet existing) niche market. But connecting some dots reveals that this might be the stepping stone needed to initiate meaningful progress in this field.

Technological lock-in

As with almost any new technology, sustainably powered jet-aircraft will have higher initial purchasing costs compared to kerosene powered aircraft, which have had almost a century of a head start now. It takes time until new technologies are optimized enough to be more widely affordable. With today’s state of the art, a sustainable aircraft would generally have half the passenger capacity, half the range, at double the upfront cost of a similar kerosene counterpart. The tech isn’t missing, it’s just locked.

In the face of initial high cost, only the creation of an aircraft with priceless performance seems fit to establish presence of this new tech in a high stake market like jet-powered aviation. - A sustainable Long Range High Speed VTOL-Jet. With other words; The ultimate means of transport, - at least within Earth’s boundary.

Entering on the higher end, the craft must offer clear practical advantages over conventional private jets in order to appeal to individuals of high net-worth. That being primarily convenient, exclusive and fast travel from point A to B. While the current state of technology and regulatory framework within Europe and the USA doesn’t deem supersonic flight feasible, the maximum efficient cruising speed of the developed J-27 is  around Mach 0.9. That is on the high end for private jets, but ground breaking. The breaking point lies within hovering flight. By combining the speed of a private jet with the flexibility of a helicopter, nearly any point within range can be landed on. But how much of a difference can that make?

A quick look:

Take Germany as an example; Considering the 14 largest cities and their airports, an average of 27 minutes is required to reach the airport, averaging 15km from the city center. The same applies your destination within Germany. Doing the maths for a 1.000km flight within Germany at 850km/h cruising speed (Mach 0.75) you get an average traveling speed of around 475km/h. Note that boarding, taxiing, clearance for take off, climb, descent are not even taken into account. Also note that 1.000km within Germany is on the high end. Most routes will fall within 400-600km, lowering the average speed far bellow 400km/h.

Best match

Considering previously stated facts, the potential benefit is greatest on these medium routes. Hence the VTOL-Jet, with a 1.000km range, could fulfill its duty well without the need for charging infrastructure at the destination point. Also thanks to this little fact, we can (for the first time) escape the never ending question for more range, since it simply isn’t the primary determining factor, anymore. (A growing range through advancements in energy storage methods would only widen the Jet’s use case.) These capabilities make the J-27 a strong candidate for Central European- and Coastal US-markets, where major important potential destinations fall within the specified optimal range. While here we generally see among the highest Take-Off-/Landing- and Parking fees on airports, avoiding these can significantly lower operational costs, offsetting some high initial cost of purchase.

But among the most important and all-deciding reason to specifically embark on the private jet sector first, is yet another.

Value your cycles

We can agree that if sustainable aircraft enter jet-aviation, they will only perform short to medium haul flights. Airlines in this business need their craft operational 12h-14h out of 24h each day, often performing four or even up to six flights per day (flight = full charge/discharge cycle) to operate cheap enough for nearly everyone to be able to afford that. Those extremely tight profit margins can only be outweighed by frequent use. That is more than 1000 flights per year, on average. Now, refueling Kerosene doesn’t hurt the tanks. But a thousand charging cycles leaves its mark on batteries. While you can expect your phone to do up to 2000 healthy cycles, an aircraft battery under extreme load will hardly do more than 500-1000 without severe signs of exhaustion. This means we need to put higher value on our cycles. That is more the case in executive small jets, which fulfill their duty successfully with 100-300 flights per year, on average. The J-27 Ignis is designed such that the battery is preserved as good as possible. But those are details about the Aircraft.

A sustainable future for aviation

Aviation is on the road of becoming one of, if not the last sector to be electrified or turned sustainable. And while most other industries’ carbon emissions are decreasing, or at least not rising each year, aviation is among the strongest growing. And there’s not much we can do about it directly now. But I think the most reasonable action we can take in that regard is the creation of the smallest possible aircraft, which makes the greatest possible difference, relatively speaking. 

In fact, passenger aircraft emit not much more CO2 per passenger kilometer than cars do. An (European) SUV does around 140g CO2 per passenger km (with only 2 passengers). A short haul flight around 135g, and a well booked long haul flight can go down to 90-100g. But it is private jet flights that exceed all charts. Depending on the model and flight route, these emit 250-650g (with 4 passengers). These numbers would be twice as high if we only got 2 passengers.

At last, no, our work is not set to only offer solutions to the exceptionally rich. Through the sheer demanding nature of the project, innovative solutions found for the J-27, can be incorporated much sooner into simpler aircraft from a different class (e.g. electric alternatives for small Turboprop aircraft, etc.). This will pave the way for some much more affordable models before the J-27 even becomes commercially available, and for future craft to come.

So in short, why start with private jets:

> Built only for rich people. But they pay the inevitably expensive price first, to enable further developments of jetliners and cheaper flights for all in the future.

> Sustainable aircraft will be more than twice as expensive than regular ones anyway. Let it at least do something yet priceless!

> Let that priceless something be what rich people value most: conveniently save time, hence money.

> Do this best at short/medium ranges where range of a sustainable aircraft (for the first time) is not of concern.

> Fit perfectly into Central European- and Coastal US-airspace operation

> Operate without paying Any Take-Off/Landing and Parking fees on the world’s most expensive airports in these regions.

> Position new sustainable aircraft within the strongest growing high value aviation sector with the greatest chance of establishing new tech

> Be the smallest possible aircraft that achieves the greatest possible CO2 reduction effect.

> Push for innovation in all areas, market individual solutions in simpler aircraft much sooner

> Ignite a strive for innovation in the physical world again.