HyImpulse Technologies

Launch companies › HyImpulse

Welcome to our in-depth analysis of HyImpulse Technologies, originally published December 15th, 2022 and most recently updated October 5th, 2026 Updated content. Make sure to check out our mission statement and why we do what we do. Look at our New Space guide if you want explanations of terms and concepts used in our research. See SL1 next to Europe’s other rockets in European rockets compared, and every first-launch date HyImpulse has given in European launch dates. And follow us on X for updates.

🚀 Update from October 2026

• Flight. SR75-1 flew on 3 May 2024 from Koonibba (Southern Launch, South Australia), hybrid motor as planned; vehicle recovered for analysis.
• Licence. UK CAA Spaceflight Operator Licence for HyImpulse UK Ltd (28 September 2026, ORS10 2026-002) for SR75 from SaxaVord; one launch in twelve months, with conditions still to clear before exercise.
• Schedule. Company target for the next Europe flight: spring 2027 (PR 1 October 2026). This replaces the September 2026 “end of 2026” target.
• Money. Series A ~EUR 15 million equity plus ~EUR 30 million public package (October 2025); Series A Extension > EUR 50 million equity (2 September 2026). Company aggregate claim: more than EUR 125 million equity and public combined. Order book “more than EUR 350 million” is a company claim (see update post).
• Company. Stammkapital now EUR 91,087 (AD after 27 August 2026). Largest holders: Schwarz Holding ~28% and HyImpulse Holding ~27%. Filed average employees 52 in 2024; the company says over 100 as of October 2026.
• Products. SL1 still the small launcher (600 kg LEO). HyMOVE is a separate Orbital Transfer Vehicle (OTV), commercial target from 2028, not a rename of SL1.

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What you should know about HyImpulse Technologies GmbH

HyImpulse: German hybrid-rocket mini-launcher, flown suborbital, licensed for Shetland

HyImpulse Technologies GmbH builds hybrid rockets that burn paraffin (wax) with liquid oxygen. The company spun out of University of Stuttgart / DLR hybrid work and is based in Neuenstadt am Kocher, with further sites in Ottobrunn and the UK.

On 3 May 2024 its SR75 sounding rocket flew from Koonibba in South Australia. That was the first commercially viable flight of the company’s hybrid motor at that scale. The next SR75 is aimed at SaxaVord in the Shetland Islands under a UK operator licence dated September 2026; the company now says spring 2027.

The orbital vehicle is still called SL1, and company materials now quote 600 kg to LEO. Separately, the accounts describe HyMOVE as an Orbital Transfer Vehicle for in-orbit mobility, with a commercial target from 2028. Do not confuse the two.

Venture capital arrived: a Series A in 2025 and a Series A Extension above EUR 50 million equity in September 2026, on top of ESA Boost! and other public contracts. Schwarz Holding remains the largest single shareholder, but no longer the only major funder.

What makes the hybrid motor special? Why fly Australia first, then Shetland? How does the funding split between equity and public money, and why do the accounts and the press releases still give different employee counts? Let’s dig in.

Launch locations: Australia flown, Shetland licensed, Oman exploring

HyImpulse has kept several pads in play since 2021. The map as of October 2026:

• Koonibba / Southern Launch (South Australia): SR75-1 flew here on 3 May 2024. That answered the “why Australia?” question from our March 2024 update: they needed a workable licence and a pad that would accept the vehicle when Europe was still slow.
• SaxaVord Spaceport (Unst, Shetland): long-standing partner; CAA Spaceflight Operator Licence for HyImpulse UK Ltd dated 28 September 2026 (ORS10 2026-002). One SR75 launch authorised in a twelve-month window, subject to conditions. Company target for the Europe flight: spring 2027 (weather + remaining licence activities), not the earlier “end of 2026” line.
• Etlaq Spaceport (Oman): letter of intent signed 2 June 2026 to explore SR75 and SL1 operations and a possible longer presence. It is not a firm booking.
• German Offshore Spaceport Alliance: older LOI; no public flight campaign executed with HyImpulse as of this update.
• Andøya / Esrange: still not the chosen Europe pad for SR75-2.

Shipping a rocket halfway around the world for the first flight was a strong signal about European licensing speed in 2024. The CAA licence and SaxaVord path are the company’s answer for the second flight. Whether spring 2027 holds is the next test.

HyImpulse’s unique and technology proven hybrid rocket motor

The story that lead to the founding of HyImpulse

HyImpulse Technologies GmbH was founded in 2018, but its beginnings date back over 15 years. Initially a student initiative launched in 2006 called “HyEnD” at the University of Stuttgart, HyEnD started developing and testing hybrid engines which lead to research initiation at the DLR Institute of Space Propulsion in Lampoldshausen. Their efforts paid off, with successful launches in 2015 and 2016, including the world record launch of HEROS3 with an altitude of 32.3 km. This led to the conceptualization of a small launch vehicle based on hybrid engines and the founding of HyImpulse Technologies GmbH in 2018 by 4 engineers, Christian Schmierer, Ulrich Fischer, Dr. Mario Kobald and Konstantin Tomilin. The HyImpulse Holding GmbH, which is the main shareholder of the HyImpulse Technologies GmbH also includes Prof. Dr. Stefan Schlechtriem, who heads the DLR Institute of Space Propulsion.

HyImpulse Holding GmbH (AG Stuttgart HRB 765123) is the founders’ vehicle. The Holding Gesellschafterliste after July 2025 shows Christian Schmierer, Ulrich Fischer, Dr. Mario Kobald and Konstantin Tomilin at 20% each, Prof. Dr. Stefan Schlechtriem at about 4.4%, and Holding own shares at about 15.6% after a transfer from Schlechtriem. On the operating company, after the August 2026 capital increase, Schwarz Holding GmbH (~28%) and HyImpulse Holding (~27%) are the two largest holders.

Building a test vehicle (SR10, SR75) and the SL1 hybrid rocket

After the successful launch of their sounding rocket test vehicle, HyImpulse’s team began developing the HyPLOX 10 engine further (HyPLOX10 stands for Hybrid Paraffin Liquid Oxygen with 10 Kilonewton of thrust). This development was followed by more research into small scale Carbon Fiber Composites (CFRP) hybrid rocket engines and the beginning of the test campaign for the 75 kN hybrid engine called HyPLOX75, to be used on the SR75 test vehicle. The HyPLOX75 will be the main “work horse” of HyImpulse’s launch vehicle, the SL1.

The SL1 is a three-stage vehicle about 27 m tall and 2.2 m in diameter. Company materials now quote a lift-off mass of about 54 t and a payload of 600 kg to low Earth orbit (older materials and our March 2024 page said 500 kg). Stage layout remains hybrid: eight HyPLOX75 motors on the first stage, four HyPLOX75 on the second (higher expansion), and a four-motor upper stage based on the smaller HyPLOX class. Optional first-stage recovery talk remains company ambition, not demonstrated.

Status (October 2026): SR75-1 has flown. SR75-2 is licensed for SaxaVord and targeted for spring 2027. SL1 has not flown; company and filed narrative point to market entry from 2027, which will slip if the suborbital cadence does.

• First Stage: 8x HyPLOX75 motors, 5 tons of paraffin, CFRP LOX tank with 12.300 litres, Gas Generator (GG) cycle with turbo pump, plus a helium tank to pressurize GG-fuel (ethanol) and LOX-tank
• Second Stage: 4x HyPLOX75 motors (capable of 100 kN due to higher expansion ratio), 2.5 tons of paraffin, same GG-cycle as first stage
• Third Stage: 4x HyPLOX25 motors (based on small scale technology demonstrator HyPLOX10 engine), 730 kg paraffin, 1.800 litres CFRP oxidizer tank, pressure-fed

The first stage is described as “optionally recoverable” with parachutes/gliders, to be picked up and disassembled, with reusable components refurbished and reintroduced into HyImpulse’s supply. Company materials now quote a lift-off mass around 54 tons with a length of about 27 meters.

Parameter	1st Stage	2nd Stage	3rd Stage
Number of hybrid motors	8	4	4
Required combustion time (in s)	100 – 120	50-80	100 – 120
Average pressure (bar)	60	60	11,5
Expanse ratio	16	41	30
Average specific impulse (in s)	~270	~321	~313
Average sea-level (1st) / vacuum (2nd/3rd) thrust (kN)	~650	~400	~100

So far, HyImpulse has achieved several milestones in their development, including:

• Over 3 successful launches of their sounding rocket and over 500+ tests on technology demonstrators
• Moving to a 1000+ square meter facility in June 2020
• Successful test of full-scale flight rocket motor TRL 7 in Scotland in 2021
• Full wet-dress rehearsal of the SR75 in August 2022, as seen below
• Engine and rocket qualification of the SR75 for launch in September 2023
• SR75-1 flight on 3 May 2024 from Koonibba / Southern Launch, hybrid motor as planned; vehicle recovered for analysis
• UK CAA Spaceflight Operator Licence for HyImpulse UK Ltd (28 September 2026) for SR75 from SaxaVord

Status (October 2026): SR75-1 has flown. The next SR75 is targeted for spring 2027 from SaxaVord under the UK operator licence.

HyMOVE: Orbital Transfer Vehicle (not a launcher rename)

In the FY2024 Lagebericht the company defines HyMOVE as an Orbital Transfer Vehicle (OTV) for in-orbit mobility. It can ride SL1 or other launchers. Commercial target: from 2028. Ottobrunn / Bayern is named for the HyMOVE Förderprojekt. Blog posts that say “Orbital Vehicle HyMOVE” mean this OTV. They do not rename SL1.

Intermission: A quick look at hybrid motors and how they compare to liquid and solid fuel rockets

What makes HyImpulse’s approach so different? There are basically three types of fuel rockets can use: Liquid, solid and hybrid.

1. Liquid fuel rockets (having “engines“) are the main choice for space-bound rockets and almost everyone uses it (SpaceX, NASA/US, Russia for the Soyuz, China for the Long March). This is because liquid fuel rockets have properties you want for launch rockets, such as high specific impulse, high efficiency, the ability to turn them off and on again etc. The downside of liquid fuel rockets is that they’re quite dangerous and engines tend to be rather complex.
2. Solid fuel rockets (having “motors“) are mostly used for missiles used by the military, such as air-to-air missiles, short-to-mid range missiles and even ICBMs, though a few use liquid fuels. Solid fuel has low efficiency and lower specific impulse, but they still give good thrust and they’re pretty safe to handle. However, once you light a solid fuel rocket, it’s hard to turn them off – and forget about full reusability.
3. Hybrid fuel rockets (having “motors“) have so far been primarily used for research, teaching and experimenting. They combine some of the advantages from solid and liquid rockets by using solid fuel and liquid oxidizers. You can therefore turn them off (and on) again, you can still get a pretty good specific impulse and they’re much safer to handle than liquid rockets. Unfortunately, hybrids still have several disadvantages: they require a fairly complex motor, expensive structures to handle temperatures (such as carbon composites), your ISP is never going to be as good as that of a liquid fuel rocket and full reusability is considered to be outright impossible.

Hybrid rockets offer an advantage over both solid and pressure-fed bi-propellant systems in certain situations. However, this advantage disappears when dealing with larger rockets or those used for orbital lift. Solids are generally better at scaling to high thrust levels because they can achieve high mass flow rates. This is because solids can be designed with a larger combustion chamber and the thrust is dictated by the propellant mix and chamber geometry, allowing for time-tuned thrust. However, solids have lower overall exhaust velocity and are typically used for short, high thrust burns. On the other hand, liquids have higher exit velocity but are limited by the flow rate of the system and the size of the combustion chamber.

Hybrid rockets combine some of the benefits of both solid and liquid rockets, with the ability to scale up like a solid and the throttle control of a liquid. They also have the advantage of a cleaner exhaust since they can use more environmentally friendly propellants.

Overview of hybrid rocket motors and hybrid engine new-space companies

HyImpulse’s hybrid fuel rocket and what they do differently

HyImpulse uses a hybrid motor with paraffin (wax) and oxygen, which are both cheap and safe to handle by space standards, and the design of the rocket structure is simple and suitable for mass production. Typically, complex cast profiles are required in solid fuel motors to increase the surface area for burning. This is not necessary with wax because, like a candle, drops detach and the wax burns on its own.

Unlike the structure however, the physics of the motor are not quite as simple. For example, HyImpulse engineers are developing vortex generators to properly mix the wax and the passing oxygen. Temperatures can also be tricky. HyImpulse is looking for a fiber composite construction for the combustion chamber that can withstand the thermal load for the duration of the burn. For fuel, HyImpulse uses a paraffin based version, which was chosen in part since it is affordable, low-toxic and offers faster regression rates than traditional polymeric fuels.

HyImpulse: Funding, capital structure and business model

What changed since March 2024

For years HyImpulse looked like a research shop funded by Schwarz Holding loans plus grants. Since the 2025–26 equity rounds, that picture is incomplete.

Equity (company-announced):

• Series A (announced 16 Oct 2025): about EUR 15 million equity (filed narrative: EUR 14.45 million plus EUR 0.85 million convertible converted). The same announcement named about EUR 30 million in public funding (Fördermittel). The company did not say which grants or contracts this covers, so it may overlap with the ESA and UK lines below.
• Series A Extension (announced 2 Sep 2026): more than EUR 50 million equity, co-led by JOIN Capital and Ace Capital Partners; North Ventures, BW-Capital, Bayern Kapital, DLR and others joined; Campus Founders and GRIF among existing shareholders who participated.
• Company aggregate claim (same PR): more than EUR 125 million in equity and public funding combined. This is a company total, not a sum of VC rounds.

Public / ESA money (not part of the equity raised):

• 2020: EUR 0.5 million from ESA Boost! through the DLR microlauncher competition.
• Dec 2022: £399,000 from the UK Space Agency for a UK test programme for its hybrid motors.
• Dec 2023 ESA Boost! co-funding: EUR 6.5 million total = £3,392,423 from UKSA + EUR 2.5 million from DLR (ESA + GOV.UK). Our March 2024 page gave only “GBP 3.5 million” or “EUR 4 million”, without the split.
• Jul 2024: £4,995,000 from the UK Space Agency for the SHARP programme, which includes an SR75 launch from SaxaVord.
• Nov 2024: further ESA Boost! / co-funded SL1 development EUR 11.8 million (company PR).
• Dec 2025: further ESA contract EUR 10.0 million, stated in the FY2024 Lagebericht; we have not found a matching public ESA press release.

Register capital (AD/CD, not the euro round size): Stammkapital path 25,000 (2018) → … → 33,329 (2022) → 46,906 (Sep 2025) → 47,561 (Dec 2025) → 91,087 (27 Aug 2026). Stammkapital deltas are not equal to announced equity euros (share premium and other instruments sit off par).

Cap table after the 7 Aug 2026 capital increase (Gesellschafterliste): largest holders Schwarz Holding GmbH (~28.5%) and HyImpulse Holding GmbH (~27%). Campus Founders, BW-Capital, Ace SPV, Bayern Kapital EFRE, GIMIC, NRW.BANK and others follow. Schwarz is still largest, but no longer alone.

YE2024 accounts (filed): revenue about EUR 2.6 million; net loss about EUR −1.8 million; cash about EUR 3.0 million; Verbindlichkeiten gegenüber Gesellschaftern about EUR 12.3 million; average employees 52. The loan-heavy structure from the Schwarz years is still visible on the balance sheet even after the later equity rounds.

Valuation

We are not publishing a point estimate. The company and the press (including coverage of the Series A Extension) did not disclose a post-money valuation. A share-count method using Stammkapital jumps produces inconsistent prices per euro of par across the 2025–26 filings, so we refuse to invent a number. We withdraw the “EUR 25–40 million” estimate from March 2024. What you can see: dated round sizes, the filed capital path, and who owns the GmbH.

HyImpulse Technologies’ business model and strategy: A few considerations

The business model of HyImpulse seems straightforward:

1. Develop a mini-launcher capable of bringing up to 600 kg to LEO.
2. Target specific niches where your advantages help, such as low lead-time from contract signing to launch, flexible scheduling, individual orbits.
3. Scale the operation and, separately, commercialise HyMOVE as an OTV from 2028.

However, going with a hybrid rocket (a decision the founders implicitly took in 2008 when they started to experiment with hybrid motors and built up their knowledge) has put HyImpulse into a smaller niche. It seems the first stage might be refurbishable to some extent. While there are different projections on the cost per kilogram of the vehicle, the overall trend has been going up slightly: In 2020, costs were projected to be at $13,000 per kg initially and $8,000 per kg once rocket motors are serially produced, statements made in 2020 have been closer to $20,000 per kg in 2023 and $15,000 per kg in 2030. In 2021 the company estimated EUR 16,000 initially and EUR 7,000 by 2030 with around 30 launches per year. In September 2026 the CEO said SL1 launches will begin at EUR 10,000 per kg and fall over time.

My opinion on HyImpulse

What I like

• They actually flew. SR75-1 in May 2024 produced flight data. Hybrid motor as advertised, recovered for analysis.
• Public research streak. The HyEnD / conference-paper culture still shows; that is rarer than PR decks. See for example here, here, here or here.
• Licence progress. A UK operator licence for SaxaVord is a concrete European step after the Australia detour.
• More sources of capital. Series A and the >EUR 50 million extension mean the company no longer depends on Schwarz loans, even if Schwarz remains the largest holder.

What I don’t like

• Slipping dates. Orbital first-flight targets of 2024 (company, July 2022) and 2025 (our March 2024 page) did not happen. “End of 2026” for SR75-2 became spring 2027 within a month. Hybrid tech is fine; calendars still slip.
• Greenwashing. Expendable “eco” rockets are still mostly branding. Paraffin/LOX is interesting engineering, but not a climate strategy.
• Headcount fog. The accounts say 52 on average in 2024; the press releases say over 100. Both can be true under different definitions, so we give both numbers and do not blend them.
• Missing from the big ESA launcher challenge cheques. Rivals collected nine-figure European Launcher Challenge contracts in 2026; HyImpulse’s public money comes mainly from ESA Boost! and UK Space Agency grants and is far smaller. That is a competitive fact, not a moral judgment.

Bottom line: The motor flew. The money arrived. The Shetland licence is on paper. What is still owed is a European flight that leaves the pad on a date the company named and meant, and a credible path from SR75 flights to an SL1 that carries someone else’s satellite.

Structured company information on HyImpulse Technologies GmbH

Updates on HyImpulse

• October 2026: Full refresh after SR75-1, the UK CAA operator licence, Series A / Series A Extension, and the filed 2024 accounts. Companion post: 2026 Update on HyImpulse. Payload now 600 kg LEO; HyMOVE labelled as OTV; valuation point estimate omitted.
• March 2024: March 2024 update (below): Australia plan, ESA Boost! money, headcount.
• December 2022: Original review published.

March 2024 update

This was a separate post from 5 March 2024. We moved it here in October 2026 and kept the facts as they stood then. What happened next is in the sections above.

• SR75 launch planned for Q2 2024 from Southern Launch in Australia. It flew on 3 May 2024 from Koonibba.
• December 2023: GBP 3.4 million from ESA Boost!, with the other 50% from “company sources”, plus EUR 2.5 million from DLR.
• 55 employees, down from 60 in 2023.

Why Australia? In early 2024 two new spaceports had opened in Scandinavia, HyImpulse had a contract with SaxaVord in the UK and a letter of intent for a site in Germany. It still shipped SR75 round the Cape of Good Hope to Australia. HyImpulse had held a MoU with Southern Launch since 2021, and launch licences and paperwork seemed much easier there. The flight was to qualify the HyPLOX engine and start full work on SL1, the three-stage hybrid launcher.

Where did the ESA money go? HyImpulse announced the funding only in a short LinkedIn post. At least part of it went to Carbon Launch Systems Ltd, a new UK joint venture between HyImpulse’s UK subsidiary and the Greek firm Adamant Composites, set up to build carbon-fibre tanks. HyImpulse held 49% of the shares and one of three board seats. The statutes read as if drafted in a rush: a vague business plan and several pages on how to break deadlocks.

Slow progress. The first target for a maiden orbital launch was 2021. Through 2023 HyImpulse moved slowly, most likely for lack of money. Hiring did not make up for staff who left, among them some SL1 project managers. Schwarz Holding, then the controlling shareholder, could have funded the launcher for years if it chose to.

All information in this analysis was obtained from public sources and we encourage you to do your own due diligence. Feel free to contact us for corrections or share our content. Attribution is always welcome.

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