For most of spaceflight history, building and launching rockets was something only governments and a few large aerospace companies could do. It was expensive, took years to develop, and only a few organizations controlled the infrastructure needed to reach orbit.

Christian Schmierer thinks it’s time for that to change.

As the co-founder and CEO of HyImpulse, one of the latest companies to join the Robin Capital portfolio, Christian wants to make it easier and more affordable for Europe to access space. He and his co-founders have been developing a hybrid rocket engine since they were students. This engine runs on liquid oxygen and a solid fuel similar to paraffin. Using fewer parts, their design akes rockets simpler, which helps cut costs and complexity for launching satellites.

But HyImpulse’s goal goes beyond building another rocket. With satellites playing a bigger role in communication, research, and security, getting to orbit has become essential. Europe has great satellite technology, but not enough independent ways to launch them. Christian believes solving this could spark a new generation of European space companies.

In this interview, Christian shares how a student rocket project turned into HyImpulse, how using a fuel similar to candle wax could change the economics of launching rockets, and why he thinks Europe still has a real shot at leading the next era of space.

About HyImpulse

HyImpulse is building launch vehicles that use hybrid propulsion, mixing liquid oxygen with a solid fuel based on paraffin. Christian and his co-founders Dr. Mario Kobald, Konstantin Tomilin and Ulrich Fisher, started working on this technology as students at the University of Stuttgart, then continued their research at the German Aerospace Center. What began as a student project, using a propulsion system that was cheaper and safer, eventually became the basis for their commercial rocket company.

HyImpulse's mission is to open access to space by delivering affordable, reliable launch and in-space services. Powered by their proprietary safe, low-cost paraffin-based hybrid propulsion, they enable customers to reach any low-Earth orbit and eliminate barriers such as high costs, long waits, and limited availability. By combining launch, satellite-as-a-service, and space-data-as-a-service, HyImpulse is committed to democratizing space and empowering broader use of space-based capabilities.

From student rockets to a space company

Christian’s passion for rockets started well before HyImpulse. He grew up near the German Aerospace Center’s rocket engine test site in Lampoldshausen, close to Heilbronn, and often heard stories about what happened there.

As a kid, he was told rockets were being launched nearby. Even though the site was only used for testing engines on the ground, this didn’t matter to him. The idea sparked his fascination with rockets and space, and eventually led him to study aerospace engineering.

When Christian began his career, the space industry looked very different. Between 2008 and 2010, SpaceX was just starting out, and topics like entrepreneurship and 'NewSpace' were hardly mentioned at European universities. Most aerospace engineering students planned to join established companies, not launch their own ventures.

“There was ArianeGroup, and in the US there was Boeing and ULA – and that was it.”

Christian wanted hands-on experience, not just theory, so in 2012 he joined a student rocket team at the University of Stuttgart. That’s where he met the people who would later become his co-founders. One of them, Mario, had helped start the student group years earlier.

Together, the four future HyImpulse founders grew the team from a handful of members to over 20. Christian says it has now grown to more than 60 and still does well in student rocket competitions.

The timing was good. The team received support from the German Aerospace Center, which allowed them to move beyond ground tests and actually build and launch rockets. Over the next few years, they built several vehicles, starting with small launches in Germany and later launching much larger rockets from Esrange in northern Sweden.

In 2016, the team set a world record by launching a student-built rocket to what Christian says was the highest altitude ever reached by a student rocket at that time. This rocket was especially important because it used the new hybrid propulsion technology they had developed.

The response from experienced people at the launch site changed how Christian and his co-founders saw their work. Engineers and specialists with decades in the industry were surprised that students had built such a large rocket. Christian explained that their propulsion technology was a big reason: it was cheaper, simpler, and safer to use.

Meanwhile, the space industry was changing. SpaceX was gaining attention, and Rocket Lab and other private companies were starting to appear. Europe was beginning to consider how to respond, but Christian noticed there weren’t many startups. By 2016 and 2017, his team started to seriously consider the commercial potential of their technology and began working on a business plan alongside their research.

Starting a company wasn’t part of their original plan. In the early days of the student team, Christian says they never talked about founding a business. The idea only became real after their technology worked and experienced industry professionals started to see its potential. In 2018, after about six years of working together, the team founded HyImpulse and began searching for their first investors and employees.

“We saw the reaction of experts who had been in the field for 20 or 30 years and thought: we have to make use of this advantage.”

Why HyImpulse is betting on hybrid propulsion

Traditionally, rockets use either liquid or solid propellants. HyImpulse combines both. Their engines use liquid oxygen and a solid fuel based on paraffin. As Christian notes, most people know paraffin from candles.

When melted, paraffin can provide about as much energy as kerosene. While it’s still solid, it’s easier to handle and store. Since the fuel is already inside the combustion chamber, there’s no need for much of the extra equipment that traditional liquid-fuel systems require.

“The best cost saving is for the parts that you don’t have to produce.”

That idea sums up HyImpulse’s approach. Rather than optimizing every part of a traditional rocket, the team tries to remove as many parts as possible. If the fuel doesn’t need to be stored in a separate tank and moved into the combustion chamber, the rocket doesn’t need all the pipes, valves, and pumps. Christian says this lets HyImpulse build rockets with about half as many parts.

These benefits show up throughout the rocket’s life. Transportation, storage, and insurance all become easier. Production and launches are simpler too. But Christian says the biggest savings come from something basic: every part you don’t need is one you don’t have to design, build, test, or maintain.

However, there was a big trade-off. When HyImpulse started, this type of hybrid propulsion was much less proven than traditional liquid or solid systems, which had been used since the early days of spaceflight. HyImpulse was trying to bring a much newer technology to market.

This meant the first six years were truly focused on research and development.

“We really didn’t know whether the technology would work in the way we wanted it to work.”

Christian points out that companies built on established propulsion methods face challenges like hiring, funding, and engineering, but they know the basic physics works. HyImpulse, on the other hand, still had to prove that its main technology could actually deliver what the founders hoped.

That uncertainty shaped how the company managed its funding. Christian says HyImpulse took a very careful, capital-efficient approach to developing rockets, thanks to both the technology and the founders’ “Swabian engineer” mindset. They made sure to control development, testing, procurement, and team growth instead of expanding too quickly.

The first successful launch of their suborbital rocket was a big turning point. HyImpulse could now shift from proving the technology to growing the business around it. After that launch, the company closed its Series A funding round in October 2025, then extended it to speed up growth.

“It is still rocket science at the end of the day, so it’s never easy. But our technology is making it more manageable and predictable.”

The taxi to space

HyImpulse isn’t aiming to build every kind of rocket for Europe. Instead, it focuses on small launch vehicles, where Christian believes customers have very different needs compared to those using much larger rockets.

He uses a simple analogy to explain. Large rockets like SpaceX’s Falcon 9 or Europe’s Ariane are like buses. They can carry big satellites or many small ones at once, which is efficient, but customers have to share the ride.

HyImpulse wants to be the taxi instead.

“We can really launch satellites exactly where they have to go at exactly the time when they want to go.”

For satellite operators, that kind of flexibility is valuable. Instead of waiting for a rideshare mission and accepting someone else’s schedule and destination, a dedicated small launcher gives them much more control over when and where their satellite goes.

Rocket Lab has already shown there’s demand for this kind of service, and Christian openly admires what they’ve accomplished. But he also wants HyImpulse to do even better. He believes their simpler propulsion design could let them offer a similar dedicated launch service for about half the price.

Building launch capacity in Europe is a top priority, but Christian doesn’t see HyImpulse as just a European company. If they can offer flexible, dedicated launches at much lower prices, he thinks there’s a global market for their service.

“We are building a company that will support the growth of the space ecosystem globally.”

Europe needs its own way into space

HyImpulse’s first suborbital rocket launch took place in Australia, rather than Europe. At the time, Christian says European spaceports were not yet sufficiently ready or available. The company’s next phase is intended to bring launch activity closer to home, with UK-based SaxaVord Spaceport planned as an important launch location for its future satellite missions.

That change matters because, for Christian, building rockets in Europe is now about much more than business.

The US leads the world in rocket launches, with China also playing a big role. Europe has strong satellite technology and related applications, but the challenge is getting those satellites into orbit.

“We are now working out how to make big business out of it. This is something that the whole space industry works on, but it will become easier when launch becomes available also in Europe.”

Christian thinks this bottleneck is even more important now, as the geopolitical situation changes. Space infrastructure isn’t just for commercial satellite companies; it also supports communications, Earth observation, government services, defense, and security. If European organizations can’t reach orbit on their own, they have to rely on launch providers from other countries.

He also sees a risk that launch capacity could become harder to find, not easier. For years, SpaceX made access to space cheaper and more available. But Christian thinks SpaceX might focus more on its own missions and goals in the future, like building its own infrastructure or aiming for the Moon and Mars. Launching satellites for other companies might not always fit with those plans.

That could leave European satellite operators, including governments and military users, with fewer choices.

“It’s a really critical infrastructure layer for both the economy, but also now security.”

For Christian, this gives Europe’s new launcher companies a shared mission, not just commercial competition. He likes the German word Mitbewerber, which suggests companies striving together. Right now, he says, Europe needs several of these companies to succeed.

He expects that only after enough launch capacity exists will the market start to sort itself into winners, niches, and different service models.

“In the next five years, it’s about ensuring that as many rockets can be launched as possible by as many companies as possible.”

Space could still be Europe’s industrial opportunity

Christian expects the launch market to become much more diverse over the next five to fifteen years. There will be both large and small rockets, some operating on fixed schedules and others launching on demand. As access improves, both commercial and government demand should grow.

But maybe the most interesting effect of better launch infrastructure is what it could mean for the rest of the space ecosystem.

Once companies know they can reliably reach orbit, more entrepreneurs, researchers, and industry players can start thinking about what they can actually do there. Christian sees low Earth orbit not just as a place for satellites, but as a new industrial zone.

He believes this gives Europe a rare chance to compete at the start of a new technology cycle, instead of trying to catch up to existing players.

“We might have lost the race when it comes to some other previous topics, including AI. But, in space, it’s not too late.”

The US is clearly ahead, mainly because of SpaceX. But Christian says that if you take SpaceX out of the picture, Europe looks much more competitive. Europe already has strong satellite expertise, engineering talent, and industrial skills. What’s missing is enough infrastructure to connect all that expertise to orbit.

Solve that, and the opportunity becomes much bigger than rockets. More launch capacity can support more satellite companies, which can support more applications and services, which in turn can make the wider ecosystem more economically attractive. For Christian, HyImpulse’s role is to help build the infrastructure on which that next layer of companies can emerge.

“Launch becomes really the critical bottleneck – everything else depends on this.”

Becoming a different CEO every 12 to 18 months

Technology isn’t the only thing that has evolved since HyImpulse began. Christian has had to change alongside the company.

His background is deeply technical. At the German Aerospace Center, he worked on everything from hybrid rocket systems to launch vehicles and lunar landers. His PhD included theoretical work on a lunar lander, while other parts of his research were closely connected to the hands-on engine development he and his future co-founders were doing through the student rocket team.

That experience prepared him well to lead technical projects, but it didn’t really prepare him to be an entrepreneur.

Christian notes that, back then, the University of Stuttgart didn’t offer much exposure to business or entrepreneurship for people in his field. So when HyImpulse started, the founders had to learn most of the business side on their own.

And that learning process is still ongoing.

“It’s a complete change that you have to undergo. Actually, I would say every 12 to 18 months, if you look back, your role has changed completely.”

As the company grows, jobs that used to be the founders’ move to new team members. Tasks that took up Christian’s time a year ago might not be his anymore, while new responsibilities suddenly appear.

In space, that increasingly includes politics.

Christian estimates that around half of his role today involves understanding the political environment surrounding space, defense and security, including government budgets and funding. A rocket company operates at the intersection of technology, business, public infrastructure and national strategic interests, meaning a CEO has to understand considerably more than engineering.

He finds this change exciting, even though he sometimes misses being more involved in the technical work. When he walks through the office, he still enjoys chatting with engineers and sometimes sharing ideas about problems they’re working on. But moments like these are less common now because he needs to use his time elsewhere.

But now, leading HyImpulse means helping other people solve those problems.

“As a CEO of a SpaceTech company, a large part of my job involves understanding and navigating politics. But it’s also a lot of fun to be an engineer and to solve technical issues.”

In rocket science, mistakes have to be visible

Mistakes are part of rocket development and Christian has come to realize that pretending otherwise doesn’t help anyone.

Instead, HyImpulse is working to create a culture where people feel comfortable making problems visible, looking into them, and learning from them.

That doesn’t mean lowering standards or avoiding accountability. In fact, Christian’s approach is to give employees more responsibility, not less. When something goes wrong, the team needs to figure out why. Was it a gap in their knowledge? Did a process fail? Was the method wrong? Only by bringing problems to light can the team investigate and get better.

This way of thinking is linked to how Christian sees the difference between big aerospace companies and startups. In a large company, an engineer might only work on a small part of a huge project, and their job ends once that piece is done.

At HyImpulse, Christian wants engineers to be involved in the whole process.

“If you’re an engineer, you have to take over the responsibility to make sure that what you think about, what you then design, that you calculate it, then you draw, then you manufacture it, then you test it, and then you launch it. You are responsible the whole way through.”

Not everyone is comfortable with that much responsibility. Christian knows that people coming from other corporate backgrounds might need time to adjust. But for those who enjoy taking ownership, it can be one of the best parts of working at a startup.

His leadership philosophy therefore has two sides: empower people to make decisions, and expect them to take responsibility for the outcomes.

For a company attempting something as unforgiving as launching rockets, both are essential.

“In rocket development, mistakes happen. So you have to have a culture that embraces mistakes so that no one tries to hide them.”

The human side of rocket science

Perhaps the biggest shift in Christian’s own thinking has had surprisingly little to do with rockets.

As an engineer, he spent years solving problems where calculations gave clear answers. Physics doesn’t care who’s in the room, and equations don’t have personal motives or communication issues.

Being a CEO is a different story.

One piece of advice Christian received early in his journey has fundamentally changed the way he thinks about leadership: always see the human side.

“It’s not about technology. Of course, in the end, it’s about making money also, but it only works if we work together as humans and as a team.”

Today, Christian says nearly every problem he faces is about working with people. He’s no longer the one doing most of the calculations. Now, his job is to align the team, set expectations, manage relationships, build trust, work with investors and governments, and keep a growing organization moving forward.

For someone who started out in aerospace engineering, learning to see problems this way has really broadened his perspective. The technology is still very important, but more and more, Christian’s job is to create an environment where others can build it.

“Every problem that I have to solve as a CEO is about human interaction.”

Quick-fire round

A tool you can’t live without?

“I’m very classical. I would say it’s Outlook at the moment.”

How do you recharge?

“When I’m not on a business trip, I try to bring my kids to bed. That's typically the best ritual of the evening. Afterward I have to work again, so it’s not really ending the day, but it’s a nice ritual which interrupts the day.”

Founder or start-up that you admire:

“Rocket Lab. The founder came from New Zealand, not the typical space nation, and built Rocket Lab up as a successful US and New Zealand company. That’s really a story that I admire. That’s also why we want to be better than Rocket Lab.”

Advice that stuck:

“Always see the human side in it. It only works if we work together as humans and as a team.”

Building the infrastructure and beyond

When Christian and his co-founders started building rockets as students in 2012, they didn’t plan to start a European space company. Fourteen years later, they’re tackling one of the biggest bottlenecks in Europe’s growing space economy: reliable, affordable access to orbit.

If HyImpulse can simplify rocket design and lower launch costs, the impact could stretch far beyond the company itself. More flexible and independent access to space could give European satellite operators greater control, reduce reliance on foreign providers, and help unlock new commercial opportunities in low Earth orbit.

Christian believes Europe still has the expertise, companies and industrial base to compete. What it needs now is the infrastructure to connect them to space.

HyImpulse is helping build that infrastructure and the team is currently hiring for people who want to be part of what comes next, check out their open positions here.