SpaceX has completed a key test necessary for development of its next Starship prototype -- stress testing a fuel tank to the point of failure, at its Starship development site in Boca Chica, Texas. This test comes on the heels of a less intense pressure test for the same tank, which resulted in a burst weld that was subsequently corrected, paving the way for the good test on Tuesday evening.
SpaceX is working on its third prototype of the Starship spacecraft at its Texas facility, which is designed to be used for high-altitude and orbital testing. SpaceX CEO Elon Musk has said that we can likely expect this version of Starship, which is dubbed "SN1," to be complete and ready for testing sometime around June based on the current development schedule.
The test SpaceX completed on Tuesday was designed to see how much pressure the tank could withstand before failure, and Musk said on Twitter that it achieved a max pressure level of 8.5 bar before the failure. That's a significant number, not only because it easily exceeds the 6 bar pressure rating that is required for an orbital flight test of Starship, but also because it matches the required number for a human-rated spacecraft, which is 8.5 bar.
Testing to failure is a crucial component of the development of any new spacecraft, because it means you can set the real-world bounds on what the spacecraft can withstand, and in actual use scenarios rather than just in simulation or in theory. SpaceX tested pressure levels for this tank at both room temperature and at cryo (deep cold levels that more closely resemble conditions the vehicle will encounter in space), with Musk noting that the deep cold actually increases the resilience of the primarily steel Starship component.
Eventually, Starship is designed to be stainless steel across its exterior surface, which Musk has said will reduce cost while also providing terrific durability and re-usability. With Starship, SpaceX intends to replace its Falcon series of launch vehicles entirely, providing one fully reusable spacecraft that can be paired with a Super Heavy booster for large loads (and trips to Mars) and that can carry either quite large payloads, or rideshare missions made up of smaller cargo from different clients.