Anthony Iemole 🇺🇦

E-2 has achieved steady expander cycle mode. In this test video, 30 seconds of expander cycle mode are demonstrated on the tail end of an 80-second test fire that began in Ox-Rich Staged Combustion (ORSC) mode. In expander mode, thrust was reduced from 23,000 lbf to 6,500 lbf, corresponding to a 28% throttle setting. To our knowledge E-2 is the first kerolox rocket engine to demonstrate a transition from ORSC to expander cycle operation on the same hardware during a test fire, thanks to our LOX cooled combustion chamber. This low throttle capability could be useful for landing burns by reducing thrust to weight ratio and providing greater flexibility to correct deviations from the planned landing trajectory.