In vacuum, no one can hear you cheer.
But down here, we still have big news to share.
Tested. Trusted. To be Fired up soon.
To all our dedicated followers, donors, and spaceflight romantics…
We know things have been a little quiet on the outside lately. But rest assured, the silence is only on the surface. Beneath it, the machines are humming, tools are spinning, code is compiling, and minds are whirring faster than a turbopump on launch day.
We’re working hard to take the next big steps toward launching a human into space. And yes—things are soon about to get loud again.
But before the roar of rocket engines fills the air once more, we’ve got a few updates to share.
BPM-25 Engine: Built, Protected, and Nearly There
The parts for BPM-25, our next-generation rocket engine, are largely complete—except for one critical cylindrical component that needs redesign. But don’t worry, there’s a method to the pause.
Instead of rushing ahead, we’ve strategically shifted our focus to BPM-17, a simplified “pipe” engine, to safely shake down our new test stand. Why? Because hard starts during early tests can be brutal—both on nerves and on engines. And when a test goes wrong, we’d rather lose a simple pipe than a regeneratively cooled masterpiece.
This approach isn’t new. We did the same when we test-fired BPM-2 before its fancier sibling, BPM-5, ever saw a drop of fuel. And now, BPM-17 is poised to follow that same philosophy: a robust test mule to pave the way for the real deal.
Once BPM-17 clears the path, BPM-25 will be next in line to fire—clean, ready, and unscathed. It’s a plan built on experience, and designed to keep our most precious engines in one piece.
The BPM-17 Engine Is Almost Ready to Roar
“Test, test, test again” isn’t just a motto—it’s our reality.
Right now, we’re putting the final touches on BPM-17, our dedicated test engine for the test stand that will test the engine that will eventually fly us to space. (Still with us? Good.)
Once ready, BPM-17 will breathe fire—and you’re invited. If you’ve never stood near a rocket engine as it ignites… well, it’s not just something you see. You feel it. In your chest. In your bones. In your soul.
This test is coming soon. Very soon. And it will mark the return of something we’ve all missed: that glorious, chest-thumping proof that our work is very real—and very loud.
Pre-Burner Hot-Fire: Making Nitrogen Flow Like Coffee
We’re not just preparing BPM-17 for its moment of glory. We’re also reviving the old BPM-5 test stand to put a small but mighty component through its paces: our nitrogen pre-burner.
Why? Because the Spica rocket needs a lot of nitrogen gas—fast—to keep its two massive 1350-liter propellant tanks pressurized during flight. Buying enough commercial pressure vessels (like firefighter SCBA tanks) was cost-prohibitive. So we found a smarter solution: bring liquid nitrogen instead, and evaporate it onboard.
Enter the pre-burner. By igniting a rich fuel-air mix to create 900°C exhaust gases, we can power a heat exchanger that vaporizes liquid nitrogen rapidly—turning about 45 liters of cryogenic liquid nitrogen into very hot pressurization gas in just 40 seconds.
It’s light, efficient, and crucially, safe—even in failure. If nitrogen flow stops, the burner won’t melt the heat exchanger. Plus, starting it up 6 seconds before launch gives us fully pressurized tanks at T0, without relying on the main engines.
The first in-house manufactured heat exchanger is ready, but before we hook it all together, we’ll test the pre-burner standalone. (Fun fact: at full tilt, the system could turn out 1.2 liters of steaming-hot coffee per second—if slightly modified.)
Expect some very warm, very exciting results soon.
From Earth to Exhibition: BPM-5 at Planetarium
One of our BPM-5 rocket engines has officially left the workshop—but fear not, it’s not on a one-way mission. It’s found a temporary orbit in the heart of Copenhagen, as part of Planetarium’s stunning new permanent exhibition.
Visitors can now see this engine up close, nestled beneath a mesmerizing live display of Earth as seen from space—a powerful nod to the “Overview Effect,” and a reminder of why we do what we do. Because someday, one of us will see that view for real.
We’re deeply honored to once again be part of Planetarium’s storytelling. Their continued support for our mission—human spaceflight, built by volunteers—is both humbling and energizing.
But remember: while BPM-5 may be on display, our workshop is where the next engines are being born. Every Saturday, we welcome curious minds to stop by and witness the future in the making. Details here.
Emergency Egress: Because We’re Flying a Human
Human spaceflight is glorious. It’s also dangerous. And we’re not just designing rockets—we’re preparing people.
Recently, astronaut candidate and parachute lead Mads Stenfatt took part in water emergency training for skydivers. The scenario? Splashdown. Heavy gear. Tangled lines. High stress. No panic allowed.
Why? Because our mission plan ends with a capsule under parachute, descending into the ocean. And the landing is only half the challenge. What happens after that could be the difference between triumph and tragedy.
We’re preparing for every possibility—because our goal isn’t just to get a person into space. It’s to get them back. Safely. Reusably. With a really good story to tell.
Check Your Inbox—You Might Be a Winner
To all our wonderful monthly supporters:
Have you checked your email recently? No pressure—but if your name was randomly drawn in our monthly supporter giveaway, you might be in for a surprise to win a “Remove Before Flight” tag and our key hanger. And if you’re not currently donating… well, you’re also not currently winning.
To get in on the fun (and help fuel the dream), sign up as a supporter at: copsub.com/support-us
Still Going Strong
Copenhagen Suborbitals is a project that demands patience. Not because we’re slow—but because we’re building a space program from scratch. By volunteers. In our spare time. From raw metal and dreams.
And sometimes, before you can build a rocket, you have to build the machine that builds the rocket.
Some of these DIY machines take months—sometimes years—to get just right. But once they’re finally running, they don’t just build a rocket—they build all the rockets that follow faster, better, and more precisely.
So yes, there are moments when it seems like progress is inching forward. But every inch is actually laying the foundation for the leaps to come.
Every bolt we tighten, every test we run, every machine we finish—it’s all pointing toward one singular moment.
And when that moment comes, you’ll be able to say:
“I supported them when it was just a crazy dream.”
Thank you, as always, for believing in us.
Stay tuned—and maybe bring earplugs.
Ad astra,
The Copenhagen Suborbitals Team
