B1046 was the first Falcon 9 Block 5 first-stage booster. It debuted on SpaceX’s Bangabandhu Satellite-1 mission on 11 May 2018, then flew Merah Putih and SSO-A before supporting the Crew Dragon in-flight abort demonstration on 19 January 2020. During that planned abort test, Crew Dragon escaped and the Falcon 9 booster broke apart as intended.