Swiss Hypersonic Startup Destinus Appears Destined For Same Path As U.S. Counterparts

Destinus uses the optimistic tagline “Reaching the Future Faster” to denote its push to develop a liquid hydrogen-powered autonomous near-space hypersonic aircraft. But like American hypersonic aircraft startups, its timeline, core mission and path to profitability shift every year, putting it on a trajectory as hyperbolic as hypersonic.

Though based in Canton Vaud, Switzerland, Destinus employs a team of about 80 engineers and aerodynamicists spread across several European locations from Germany and France to Spain. The last is important to the young company (established in 2021) which has just received two research grants from the Spanish Ministry of Defense.

The first funds the construction of a test facility near Madrid for air-breathing hydrogen engines which Destinus will participate in design of with Spanish engine OEM, ITP Aero. A second grant funds research into aspects of liquid hydrogen-powered propulsion with a view to adapting existing jet engines to future supersonic hydrogen-powered aircraft.

Together, they’ll funnel about 10 million Euros to Destinus, according to company founder Mikhail Kokorich. Their importance is as symbolic as financial since they represent, along with a smaller grant from the European Union’s Horizon research fund, the only outside work the startup has thus far attracted. They add to $29 million in seed funding Destinus raised from private equity last February.

In total, the company has raised about $50 million so far according to Kokorich. That’s a long way from the “billion [Swiss] Francs” or about $1 billion Kokorich has been quoted as saying it will need to realize its ambition to build a commercial hydrogen powered hypersonic airplane.

What sort of hypersonic airplane it will be and when we’ll see it are familiar questions for anyone who’s followed American startups like Hermeus and Venus or would-be supersonic makers from Boom and Aerion to Exosonic. The answers are typically as liquid as, well… liquid hydrogen.

The Fast Future

Destinus lays out its vision in the post Why Mikhail Kokorich is Building a Space Startup on its company website. It’s a vision Kokorich has repeated for a number of media outlets in the past couple years. In short, it goes like this;

Destinus wants to revolutionize air transport with a hybrid hypersonic aircraft that combines hydrogen-fueled air-breathing turbojet engines for takeoff, landing, and flights at subsonic and supersonic speeds with a separate cryogenic (ramjet) rocket engine which will boost the aircraft to hypersonic speeds. The result will be an hyperplane that climbs to near-space altitudes, accelerating to Mach 15. It’ll be able to reach Australia from Europe in 90 minutes “in a climate-neutral manner”.

But unlike its American counterparts, Destinus has not aimed to build unmanned subscale hypersonic airplanes for the military before ultimately developing and flying a hypersonic airliner. Instead, the company aimed to build a hyper-fast freighter aircraft, able to deliver urgent air cargo anywhere on the planet in six to 12 hours instead of the current 24-72, “and at a comparable cost”.

Destinus has claimed this will happen at what most would consider hypersonic speed. The first commercial intercontinental flights of its air freighter (with a payload of one ton) “are planned for 2025,” its in-house blog says, “with a final stage of 100 tons across the globe by 2029. Thousands of hyperplanes and 1000 employees are expected to be in operation by then.”

Where thousands of hyperplanes might come from is anyone’s guess. Other private sector hypersonics firms I spoke with on background concede that commercial hypersonic planes are many years over the horizon and even then, likely limited in number.

Though we didn’t discuss this conventional wisdom specifically when I spoke to Kokorich last week, he seemed undaunted by the prospects of the hypersonic airplane business.

Destinus’ founder is a Russian emigre whose background includes founding in-space transportation and infrastructure company, Momentus, as well as other space and consumer goods firms. Kokorich exited Momentus in January 2021 after the U.S. government expressed national security concerns related to ownership.

That led to a move from California (where Momentus is based) to the capital-friendly climes of Switzerland and the founding of Destinus. Despite his somewhat messy exit from Momentus – the company recently finalized a share repurchase agreement for a final payment of $10 million to is two founders, Kokorich and Lev Khasis – Kokorich is generally well-regarded by others in the private sector hypersonics game.

The affable and breezy way in which he answers questions about his new company is pleasant but obscures what is surely a sensibility that puts an attractive sketch of future plans ahead of pesky real-world details. One of these is the reality that reusable hypersonic aircraft will emerge first as subscale drones for military and research applications.

Destinus has itself taken a couple steps down the drone path, flying a subscale, remotely-piloted subsonic prototype called the Jungfrau (in a nod the Swiss mountain) in November 2021 and following up with another slightly larger prototype drone (Eiger) which flew in October 2022.

The test flights appear to be relatively straightforward data-collection exercises focused on the fairly generic waverider hypersonic vehicle shape (see Hermeus’ Quarterhorse, NASA’s X-37B and others) and a basic remote guidance system. The drones have flown with power from a General Electric J85 turbojet, a familiar compact engine choice for supersonic and hypersonic aircraft developers like Boom and Hermeus.

Though these others are using single or multiple J85s for development (in Boom’s SB-1 demonstrator and Hermeus’ Chimera Turbine Based Combined Cycle engine), Destinus is distinguished by the effort it is said to be making to convert more powerful off-the-shelf production engines to run on liquid hydrogen for the subsonic to supersonic portions of its hyperplane’s flight envelope.

The company plans to take a go-it-alone approach in developing an in-house engine for the hypersonic portion of its mission. In a company video, it says it will design and assemble reusable production-certified hydrogen-fueled ramjets – a daunting undertaking for any established aerospace engine maker, let alone a startup.

The plan reminds me of Boom’s recent decision to self-develop a powerplant for its Overture supersonic airliner – a decision driven by necessity in the absence of any existing engine OEMs willing to partner with Boom despite the company’s attempts.

The Destinus team likely recognizes the slim chance of attracting a major engine-maker to develop a reusable rocket for its hyperplane without a massive tranche of funding in hand and the willingness to wait-out years of R&D.

After all, launching an autonomous hypersonic hydrogen-powered air freight airplane with a 2,ooo-pound (907 kg) payload of urgent cargo on a revenue flight by 2025 is not an exercise in patient goal-setting.

Unless you move the goal posts.

“We Changed Our Opinion”

Among the most fascinating (or frustrating) things about the aerospace startups of the last decade is their eagerness to declare they will have product X ready for prime-time, profit-making operations by date Y no matter how unrealistic the timeline or technology. No one, besides breathless investors, forced them to make such bold public commitments.

Advanced Air Mobility, supersonic and hypersonic transport startups seemed not at all bothered by over-promising, so long as they could attract and keep venture capital flowing through the door. But the days of throwing money at air taxis and new-age Concordes are rapidly coming to a close. So are the “aggressively-near” business plans of both nascent firms like Destinus and new but established players like Joby.

It’s not surprising then that in the course of about a year, Kokorich has changed Destinus’ tune. “We changed our opinion,” he says with a smile when pressed on how his company would fly a hypersonic air cargo airplane in 2025.

Now, rather than plunging into the expedited air freight market (a market Destinus reckons is worth $60 billion), the startup is pivoting to developing a 25-passenger hypersonic air transport aircraft. Follow-on planes will be progressively larger, up to 100 passengers and beyond.

The first 25 passenger hyperplane should be taking off from 10,000-foot runways at a selection of somewhat remote (for noise reasons) international airports by 2030 or 2032 Kokorich says. Unsurprisingly, the scheme and the timeline sound almost identical to those laid out by Beijing-based Space Transportation, Hermeus, Venus or Boom.

Naturally, the hypersonic aircraft details among these would-be players differ. (Space Transportation’s virtual video of its hypersonic space plane landing vertically a la Space X’ Falcon 9 is particularly entertaining though I can’t figure out how passengers are going to de-plane from it?)

But the common threads – shrinking the world, delivering urgently needed goods or people, and being carbon-neutral – are firmly shared. Based on its revised emphasis, Destinus is now on the same path.

This year or next, the company plans to fly a supersonic drone, basically adding an afterburner to the J85 it has already used, a configuration familiar to any U.S. Air Force pilot who has flown the T-38 or F-5. It’s a rational choice though, strictly speaking, at odds with Kokorich’s contention that Destinus will not use any American technology.

Given the time available, the supersonic drone probably won’t be liquid hydrogen-fueled though it wasn’t clear if the possibility has been ruled out. The drone will again be remotely-piloted, a human-in-the-loop control strategy Destinus seems to be coming around to. That’s likely because the specter of a fully autonomous passenger-carrying hyperplane is one international regulators are unlikely to embrace any time remotely soon.

Accordingly, Destinus’ senior development manager, Martina Löfqvist, recently told an interviewer that, “The future passenger airplanes will be a combination of autopilot systems and human pilots, where the autopilot will be primarily used during hypersonic acceleration and cruise.”

She added that those future airplanes will likely need four as-yet-unspecified in-production turbofans and that “for bigger passenger-carrying vehicles, we may still have to consider developing an engine ourselves.”

The details of Destinus’ ultimate propulsion system are still in the air and it’s all rather confusing unless you’ve been following along closely. While a smaller hyperplane may use the multi-turbofan/ramjet rocket combo as described above to haul passengers (and maybe light cargo), larger versions up to “Airbus A380-size” Kokorich says, may use a hydrogen-fed air turborocket (ATR) for hypersonic flight.

Destinus engineers have reportedly produced a prototype compressor for the ATR engine, suggesting either promise and technical progress or alternately, parallel research unrelated to getting a minimum-viable product to market in the hazy future. To be fair, the myriad yet-to-be-worked-out details for the startup put it in the same boat as its competitors with the possible exception of Hermeus.

They include proving that a Destinus hyperliner ticket could be as cheap or cheaper than a Concorde ticket in present-day dollar terms. The current vogue for such proposals is to compare them to the cost of contemporary business or first-class fares. These hinge on a set of far from certain assumptions which in Destinus’ case include a reduction in the cost of liquid hydrogen fuel.

Liquid hydrogen is currently around $16 per kilogram which roughly translates to around $58 per gallon. Jet fuel is about $2.60 per gallon. Kokorich rightly points out that there are a number of international research and development initiatives aimed at reducing hydrogen prices underway which could make liquid hydrogen significantly cheaper.

But closing the gap above seems unlikely even a decade from now. In addition, forecasts predicting lower hydrogen costs fail to factor rising renewable energy input costs. These will be further aggravated by the negative environmental fallout now increasingly recognized with offshore wind farms, geothermal projects and continued opposition to nuclear technology.

Liquid hydrogen is also five-times as expensive to ship as liquid natural gas and far more expensive than oil. What’s more, international airports have no hydrogen infrastructure. They will only be persuaded to build it by being offered huge injections of money or by clamoring demand from passengers. As of yet, global airline passengers have shown little hunger for supersonic airliners let alone hypersonic aircraft.

If it’s not safe to assume that hydrogen costs or infrastructure will change in major ways any time before 2040 (a notional date picked by some studies), then it’s simply not logical to assume a liquid hydrogen air transport plane will be price competitive with current air transport planes.

It’s a reality that holds even when Kokorich’s claims regarding the shorter fuel-burn times associated with hypersonic speed, altitudes and flight profiles are factored in. And Destinus, like every other hypersonic startup, has no real-world operational data with which to back its claims.

The Best, Not The First

How will Destinus distinguish itself in the notional hypersonic air transport market which might one day come? “Our goal is to be the best, not the first,” Kokorich says.

The obvious turnabout from Destinus’ initial promises doesn’t trouble the company founder who asserts that Europe’s Airbus was founded long after America’s BoeingBA
but has since become the better company, building a better plane. Destinus will distinguish itself by sticking to its liquid hydrogen fuel strategy and heading for the commercial market.

Other hypersonic companies he says have stayed away from hydrogen because “hydrogen is hard”, Kokorich says. This is partly true though Venus plans to use a Space Shuttle-like combination of liquid hydrogen and liquid oxygen in its yet to be fully developed rotating detonation rocket engine. The challenge of liquid hydrogen will likely delay Destinus progress Kokorich acknowledges but its benefits (superior engine cooling and assumed low emissions) are worth sacrificing first mover status for.

The company may get some of the time lost back by focusing on a direct to commercial market path rather than going the military drone development route that American startups are taking on their way to eventual airliners. Kokorich maintains that commercial aircraft are Destinus’ priority. Yet when asked if his company can raise sufficient money to proceed without taking military or government sponsored funding to bridge its efforts, he prevaricates.

“We’re definitely going to work with the military but in a different sense,” he says without specifying how before shifting back to liquid hydrogen as a differentiator. Europe, I point out, has raised its investment in defense since Russia rolled into Ukraine but it is still spending far less in per capita terms on defense than America. Will there be enough defense-related interest in what Destinus is doing to help maintain its longer term R&D?

“We believe that in Europe there is enough money and resources to support great aerospace projects. The combined European GDP is bigger than the U.S. The example of Airbus shows that we can build a great aerospace company in Europe so we don’t see why [we] can’t be successful.”

Kokorich opines that Destinus can continue on its development path by nature of its pan-European operating locations and gaining access to local development programs. That suggests he’s already thinking of Destinus as an aerospace R&D subcontractor alongside its visions of hypersonic glory.

The company could even survive in a scenario where it does not attract additional funding. “We just go with this money [already raised], grow and still build our supersonic [drone]. We are planning to raise some funds but I don’t want to announce [whether] it’s this year or this amount before we do this.”

There does not appear to be a specific timeline for Destinus’ investors to realize a return or a detailed timeline to profitability. Kokorich says his early investors may in future reap a return from selling their stakes and he hints that the company may go public at some point.

Long term profitability may not be a pressing issue Kokorich says, pointing to Space X, which he maintains isn’t yet profitable. Analysts conclude it’s difficult to tell since Elon Musk’s company (which ironically recently signed a deal with Momentus) is private. Nevertheless, Destinus is not Space X. Nor is any other hypersonic startup.

But they’re all on a similar path, one Destinus increasingly appears to be sticking to. Its attraction lies partly in the fact that the startups on it largely settle their technical and business goals on ever-shifting sand. The next development is always a moving target – like a hypersonic airliner or a hypersonic weapon.