On January 16, 2025, SpaceX's Starship rocket embarked on its seventh flight test from Starbase in Texas, successfully demonstrating the Super Heavy booster's return and catch capability. The booster, powered by 33 Raptor engines, executed a full duration burn during ascent and relit 13 engines for a landing burn, resulting in a historic second successful catch by the launch tower arms. This achievement marked a significant step forward in SpaceX's goal of developing a fully reusable rocket system capable of rapid turnaround times.
“Preliminary indication is that we had an oxygen/fuel leak in the cavity above the ship engine firewall that was large enough to build pressure in excess of the vent capacity.”
However, the upper stage Starship encountered issues after separation, with a flash and pressure rise detected in the aft section near a Raptor vacuum engine. Sustained fires led to the controlled shutdown of all but one engine and loss of communication eight minutes into flight. The vehicle broke apart during descent, with the Autonomous Flight Safety System triggering as expected. SpaceX identified a strong harmonic response as the probable cause, leading to propellant leaks and fires in the attic area. Elon Musk commented on the incident, stating, "Preliminary indication is that we had an oxygen/fuel leak in the cavity above the ship engine firewall that was large enough to build pressure in excess of the vent capacity." Debris landed within the planned response area, and SpaceX coordinated with authorities in Turks and Caicos and the UK for cleanup efforts, ensuring no significant environmental impact.
Following the anomaly, SpaceX conducted an extended duration static fire test with the Starship vehicle slated for the eighth flight, testing multiple engine thrust levels and hardware configurations to address the harmonic response issue. The company is implementing fuel feedline changes, propellant temperature adjustments, and a new thrust target for the next flight, while also adding vents and a nitrogen purge system to mitigate flammability risks in the attic section. Despite the setback, the flight test showcased progress in SpaceX's pursuit of full and rapid reusability, with lessons learned informing future upgrades like the Raptor 3 engine, as the company continues to push the boundaries of spaceflight technology.