A significant setback occurred for SpaceX on Friday when Booster 18, the first upgraded Block 3 Starship Super Heavy booster, was damaged in an explosion during ground testing in South Texas. The booster, stationed at the Massey test site near Starbase, was subjected to routine gas-system pressure tests when its massive liquid oxygen tank unexpectedly ruptured. The incident, which took place around 4:04 a.m. local time, was captured in live footage showing the lower portion of the approximately 70-meter-tall booster crumpling and partially disintegrating, sending debris and gas clouds into the air.
Despite the explosive nature of the event, the 20-story rocket remained upright; however, post-event analyses revealed a substantial hole in the liquid oxygen tank and significant structural damage to its aft section. SpaceX reported that Booster 18 experienced an anomaly during the gas system pressure testing phase and reassured the public that no propellant had been loaded into the vehicle, nor had the Raptor engines been installed. Furthermore, all personnel were maintained at a safe distance during the testing, resulting in no injuries.
Initial investigations suggested that the failure may have been caused by a composite overwrapped pressure vessel (COPV) housing high-pressure gas, located within one of the booster’s chines. This likely failure triggered a chain reaction that led to the rupture of the liquid oxygen tank. Booster 18 was crucial for supporting Flight 12 and commissioning SpaceX's new Pad 2 infrastructure at Starbase, making this incident a notable hindrance to the Block 3 development schedule.
Given the extent of the damage, analysts predict that the next test launch of the Starship and the initiation of the V3 architecture could be postponed until a suitable replacement booster, possibly Booster 19, is constructed and delivered to the launch pad. SpaceX has emphasized that rapid testing, including instances of failure, is vital for refining a fully reusable super heavy-lift system pivotal for missions involving Starlink, deep space exploration, and NASA's Artemis lunar lander program.