Rocket Factory Augsburg AG (RFA) has successfully hot fired the company’s upper stage for a full duration of 280 seconds — this marks the successful completion of the Integrated System Test (IST) campaign, wherein a staged-combustion Helix engine was integrated into an upper stage tank system and hot fired several times prior to completing the full duration in the final test. This is the 1st time in Europe that a privately developed staged combustion upper stage has been successfully hot fired.
In the now successfully completed IST campaign, all stage level systems and components were tested. The final test was a full duration burn of 280 seconds. This makes RFA the 1st private company in Europe to successfully hot fire a stage with a staged-combustion engine for its full duration. With this long duration burn, the Helix engine is now qualified at the same time for both the first and second stage flight.
The campaign, which was conducted at Esrange Space Center in Sweden, is the most important milestone in the development process so far: 280 seconds of steady-state combustion proved the functionality and compatibility of all upper stage systems, including fueling processes, fuel management, pressurization, sensors, propulsion and control. Valuable data was collected for further engine and stage optimization. RFA will now focus on the assembly of the first stage and continue the construction work on the launch pad.
In July of 2021, RFA became the first company in the European Union to successfully develop and test a staged combustion engine with a successful eight-second hot fire test. This made RFA the third commercial company in the world to successfully test a staged combustion rocket engine on a large scale. This was followed in August 2022 by a hot fire campaign of the Helix in flight configuration with a total burn time of 74 seconds. The same engine was fired and stopped three times without having to replace any components.
The staged combustion technology is characterized by higher efficiency and performance compared to conventional open-cycle rocket engines. The partially unburned exhaust gases from the turbopump are fed into the main combustion chamber, avoiding the release of unburned fuel. Recycling the exhaust significantly increases the efficiency of the launch vehicle while reducing launch costs and minimizing CO2 emissions during rocket launches.
”The upper stage performed flawlessly and ran through the full 310s autosequence without tripping any redlines. The engine run-time was 280s and no damages could be identified after the test. This is the first successful qualification test of our upper stage, and we are super proud of our team for designing, building and testing in such a time- and cost-efficient fashion. The data we have collected will allow us to tune all stage sub-systems, for both the upper and first stage. Our next big step is the first stage hot firing test. We are approaching our first launch with great strides, it is getting serious.”
— Dr. Stefan Brieschenk, COO, RFA
“This successful test is a massive leap forward for us. It’s a full confirmation of our strategy to develop a small launcher that is both very powerful and achieves cost-leadership. With this full duration test we have demonstrated again that we are able to complete more milestones with less, but smarter investments than any of our competitors.”
— Dr. Stefan Tweraser, CEO, RFA
