SpaceX Booster 18 suffered an anomaly during gas system pressure testing… No propellant was on the vehicle, and engines were not yet installed. The SpaceX teams need time to investigate before they are confident of the cause.
There were no engines inside. There was no damage to the site.
This is not unusual for a first-of-type article. SpaceX has bounced back from worse and iterates extremely quickly. This will have some weeks of delays.
Booster 18 suffered an anomaly during gas system pressure testing that we were conducting in advance of structural proof testing. No propellant was on the vehicle, and engines were not yet installed. The teams need time to investigate before we are confident of the cause. No one…
— SpaceX (@SpaceX) November 21, 2025
Booster 18 (B18) was undergoing gas system pressure testing (using inert gases like nitrogen/helium to pressurize tanks and lines). This was preparatory for full structural proof testing and cryogenic propellant loads. No liquid propellant was onboard, and no Raptor engines were installed yet (engines are added later in the process).
The booster suffered a catastrophic failure — the lower section (around the liquid oxygen tank area) crumpled and partially collapsed. Livestream footage showed the structure buckling dramatically, with visible deformation and what appeared to be a rupture/explosion-like event from overpressurization.
B18 is almost certainly a total loss and it will be scrapped. There were no injuries — personnel were at a safe distance, as is standard for high-risk tests. The site was cleared for investigation.
Why This Matters for Starship V3
Booster 18 was the first version 3 booster and includes major upgrades. It has thicker steel in some areas, redesigned downcomer pipes, improved tank commons/domes, and changes for higher reliability/rapid reuse.
V3 boosters will have more payload.
This is a setback of a few weeks to months while SpaceX analyzes root cause. It could be a weld, bulkhead, or pressurization control issue. They will then change the design and fix Booster 19+.
Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
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