RFA successfully tests staged engine

"The successful test of our full-scale staged combustion engine underpins our claim to market leadership," said Dr. Stefan Brieschenk, the company's chief operating officer. "With our technology, we can deliver 30 percent more payload to space at the same cost to the customer," added Jörn Spurmann, chief commercial officer of RFA.

This is made possible by the fact that staged combustion is characterized by higher efficiencies and performance compared with conventional rocket engine designs. The recirculation of partially unburned exhaust gases from the turbopump to the main combustion chamber also avoids the release of unburned propellant and significantly increases the overall efficiency of the launcher. Efficient combustion of the propellant (hydrocarbons and liquid oxygen) can reduce launch costs while minimizing the CO₂ footprint of launch activities.

Staged combustion engines are best known for the SpaceX and Blue Origin engines already in service. Both Raptor (SpaceX) and BE-4 (Blue Origin) rely on this mode of operation, which forms the technological backbone of some of the world's most successful space companies. So far, however, it has only been used in China, India, Japan, Russia, Ukraine and the United States.

With the successful test run, RFA can now compete in the global race for low-cost rocket launches. The 3-stage launcher is 30 meters long and is said to be capable of delivering up to 1.6 tons into ISS orbit. Into geostationary orbit (36,000 km altitude), 450 kg should still be possible. The first launch is scheduled for the end of 2022 from the Norwegian Andøya Spaceport. Launch sites in the North Sea and the Azores are also under discussion.

To market the rocket, RFA entered into an agreement with Exolaunch, a German rideshare provider. As early as March 2021, OHB's Swedish subsidiary awarded RFA a contract for the launch of a satellite in 2024. In order to be able to meet these deadlines, RFA is pressing ahead with the development of all the necessary components.

Two planned milestones were already achieved at the beginning of May this year: In the so-called "power pack test," the turbopump and preburner were started and operated in a stable, steady-state thermomechanical condition for a total burn time of 8 seconds. In the next development step, the first ignitions of the main combustion chamber were carried out, after which the test team connected the "power pack" to all systems of the full-scale engine and carried out the complete system-level test.

via RFA, OHB, Exolaunch