Archimedes engine family

Rocket Lab’s Archimedes family is a reusable liquid-methane/liquid-oxygen oxidizer-rich staged-combustion engine family under development for Neutron. Rocket Lab’s Neutron guide specifies nine first-stage Archimedes engines with 6,600 kN total sea-level thrust, turbopump feed, 65% minimum throttle, and restart capability; the separate Vacuum Archimedes child preserves the one-engine 900 kN vacuum-stage boundary.