What. A. Sight! 😍 Our upper stage with a Helix engine. Ready for Integrated Systems Testing (IST) to validate the full #functionality & compatibility of all systems. How? With a #hotfire over its entire flight duration. Here, all stage systems are tested simultaneously. (1/3) pic.twitter.com/CEWuF7NHYL

— Rocket Factory Augsburg (@rfa_space) November 7, 2022