Newsletter #1 — 2024 year in review
Dear readers, welcome to our very first newsletter! We decided on this format to keep you better informed about what's happening in our team, our project progress, and our future plans. We'd like to publish the newsletter regularly, roughly once a quarter, in line with our project milestones.
Our last meeting with you was on August 17 at Bezno airfield, where we launched our Illustria rocket for the second time this year. Despite the bad weather, we launched and consider the day a great success. Thank you for being there with us! At the same time, we identified areas for improvement, such as guest facilities, which we'll take into account for future events.
You can find more information about our launches in our press releases, including photos and videos. You can reach them via the button in June or via the Media tab.
Events
This year was full of activities and events. At some of them, our Illustria became the centre of attention:
Presentation of the "Czech Path to Space" project (June 20, 2024): The event focused on preparations for the mission of Czech astronaut Aleš Svoboda, who is expected to fly to space within 5 years. At the follow-up event in Brno we presented our project in detail, and Illustria was on display in the main hall at both events.
Czech Space Week (October 2024): A conference where we presented our results and future plans during a panel discussion. We were represented at the event by our new team lead, Matyáš Starosta.
Trade fairs (October–November 2024): We took part in the International Engineering Fair and the Gaudeamus fair, where alongside Illustria we brought samples from our tests and flights. We consider both events a success and were pleased by visitors' interest.
News
Recruiting and onboarding new members:
This year's recruitment brought more than 40 new members into the team. To help them integrate as smoothly as possible, we run workshops covering the basics of rocket design, working with our equipment, and our software. Last year we underestimated how much support newcomers needed, and this year we wanted to fix that.
Handover of leadership: In September we said goodbye to members who successfully finished their studies, including most of the team's leadership. Matyáš Starosta became the new team lead, Vojtěch Ježek chief engineer, and Michael Jurča secretary. Leadership of the individual groups was also handed over to active members.
Workshops
Since the start of October we've held several workshops for new team members. For the whole team, we ran a big workshop called "How Rockets Work", led by our chief engineer. We discussed the basic principles of rocket systems and presented the vision for our future rocket. This was followed by Safety Training focused on working in the workshop and during testing. The programme then split by group:
In Propulsion, workshops covered grain geometry design for a small solid motor, combustion chamber calculations, and construction able to withstand the pressures and temperatures generated during combustion. This was followed by an introduction to our current fuelling solution and our engines.
The Structures group focused on the Illustria rocket, specifically flight profile design, nose cone and fin selection, and working with aerodynamic stability. There was also training on working with 3D printers, including choosing suitable materials for prototypes.
As always, the Avionics group ran the most workshops. New members learned to program in the STM32Cube development environment, design PCBs in KiCAD, solder, measure electrical quantities, and test systems. These larger sessions were followed by mini-workshops, where more experienced members presented individual parts of the systems.
The workshops were followed by joint working days, during which we collaborated on larger projects for the first time, working on:
- Manufacturing new tail fins and a new engine mount.
- Repairing older flight components for future display.
- Preparing new parts for testing.
During these days everyone got hands-on practice with:
- Working with composites – from cutting and laminating to bonding.
- Manufacturing and safely preparing rocket motors for the coldflow and hotfire tests we ran this semester.
- The basics of machining, including turning, milling and drilling.
Testing
Testing most of our components is an essential part of what we do. Test results let us catch flaws and weaknesses in our design and improve on them going forward.
Phoenix hybrid engine
1. First test: The engine ignited successfully, but didn't reach nominal performance due to low tank pressure. 2. Second test: Both combustion chambers failed – the first due to a faulty bonded joint, the second burned through because of cracked insulation. These issues were addressed in the new chamber design.
Medusa and Kerberos solid motors
These motors were tested three times in total. The goal was to improve thrust curve stability and refine grain manufacturing using silicone moulds. Improvements included installing more accurate temperature sensors to verify our calculations.
Coldflow test
Because of the chamber damage, we ran a so-called coldflow test, in which every component except ignition was tested. The test included new quick-disconnect fittings and doubled as a workshop for newcomers, during which we demonstrated and tested our launch procedures.
Final tests of the Phoenix hybrid engine
The last test of the old hybrid configuration ended early due to a recurring problem with the main valve at low temperatures. Further tests will only take place on the new configuration.
Manufacturing
Replacing and improving flight parts
For the planned Illustria launch we needed to manufacture new tail fins and a new engine mount. Both parts are very similar in shape but went through minor tweaks that will be used when manufacturing the new tail fins and engine mount for the new rocket. (The new rocket will have different geometry, so these particular parts can't be reused.)
The tail fins were reinforced with a foam core for better stiffness and possible impact resistance. On the engine mount, the bonded joint was redesigned and subsequently tested to 3 kN.
Display models
Since the damaged parts aren't destroyed, we decided to repair them and turn them into display models. The tail fins were reinforced and the engine mount bonded back together. The same goes for the avionics section. All these parts are in very good shape, but we can't risk them failing on another flight.
Engine mount – bonded joint validation
The new engine mount for the new rocket has been fully designed, and FEA analysis and validation of the bonded joints is currently underway. Samples matching the designed solution were manufactured to test the bonded joints. The first bonded-joint tests have already taken place and revealed an adhesion defect between the adhesive and the carbon tubes, likely due to insufficient sanding of the bonding surface.
Avionics
Over the past year we've improved every part of our avionics system – from flight computers and in-rocket wiring, through batteries, to ground systems and telemetry. All these systems are backed by our own battery packs, the so-called Bobešové. They handle not only the safety systems but also charging and balancing the batteries on the rail.
The new avionics work isn't limited to the rocket, though. Our ground systems went through an iteration too. We decided to use the experience we've gained to improve everything we could. We're building our systems so that in the coming years we can free up our hands for other projects and just fine-tune a modular system.
New composite tank
Our current tank has good properties, but we know a better one can be designed and built. One team member chose it as the topic of their master's thesis. The new tank we're currently manufacturing will serve both N2O and ethanol (fuel for the liquid engine). All pressure will be carried by carbon fibre, while an aluminium foil liner will provide separation from the media, since epoxy doesn't get along well with N2O.
We currently have a winding mandrel printed and RADAX fittings manufactured, modified from the universal variant so they can be fully wound in and form a single module that simply connects to the rest of the rocket's parts.
Liquid engine
We're starting with hybrids, but we don't plan to keep one as our main engine long-term. Once it's dialled in, we plan to replace it with a fully liquid engine, with which we'd eventually like to fly higher than 9 km. Work on the liquid engine began as part of two master's theses. We've currently tested the fuel injector and a 3D-printed steel nozzle from our partner Beneš a Lát. We're very excited to be able to work on the liquid engine full-time. Of course, we know it's a long road, but we think that early next year we could test a full coldflow and, if all goes well, a subsequent hotfire.
Illustria
Our largest rocket, Illustria, has been with us for almost two years, and that's why we wanted to give her a proper send-off with one last flight. This flight was meant to be a symbolic close to the project and a farewell to departing team members.
Additional tests were meant to ensure the rocket would land safely and the flight would go smoothly. Unfortunately, testing revealed problems with the main valve, which didn't work correctly at low temperatures. Since we couldn't guarantee this fault wouldn't recur at launch, we decided to retire the Illustria project.
This decision was also influenced by how time-consuming maintaining the old configuration had become. It risked leaving us without enough time to work on the new competition rocket for EuRoC 2025. Retiring Illustria now lets us focus fully on developing and building her successor.
New rocket
For next year we're preparing a new rocket, which will carry the name Andromeda. This rocket will feature significantly improved systems. Our goal was to fix and refine as many parts as possible, to build a foundation we can keep drawing on in years to come. This will give us more room for long-term projects, since designing and building a rocket in a single year is extremely demanding.
Andromeda is already largely developed, and manufacturing and programming are currently underway. Some parts are already finished, and we plan to have the whole rocket assembled before summer so we can carry out a test flight over the summer. Before that, however, partial tests focused mainly on the electronic systems may take place.
Academic activity
Writing theses is also part of what we do. Given how demanding both studying and working in the team are, most members find it ideal to combine the two as much as possible. Over the past year our members worked on the following topics, with more planned for next year.
Master's theses
- 2024:
- Nozzle and combustion chamber design for the liquid engine.
- Design and manufacturing of the fuel injector.
- New test stand for engines up to 10 kN.
- Design of a new fully composite tank.
- Design of the Cimrman main flight computer.
- Planned for 2025:
- Combustion simulation system.
- Measuring the burn rate of hybrid propellant.
Bachelor's theses
- 2024:
- Development of the fuelling system (hardware and software).
- Active control of a test rocket.
- Modularisation of measurement systems and miniaturisation of the main computer.
- Planned for 2025:
- Development of a new main valve and a burst disk overpressure protection element.
Conclusion
Thank you so much for your support in every area. We're very glad we get to be on this journey to the stars together with you. And we hope we'll keep flying further together – this time with Andromeda, which we're working on intensively.
Season summary
The team continues to develop its projects and technologies, and can now boast its first generation of graduates who successfully completed their studies. A number of members have also defended theses based on team activities. Over the past period the team achieved two successful rocket launches and continues to test new components intensively. It is currently focused fully on developing the Andromeda rocket, while in parallel starting work on a liquid rocket engine, which represents a significant step forward in technical development. Growing our partnerships, which provide valuable support and expert know-how, is also an important part of our progress.