This week, SpaceX workers in South Texas loaded the third full-scale Starship prototype—SN3—onto a test stand ​at the company's Boca Chica launch site. On Wednesday night, they pressure-tested the vehicle at ambient temperature with nitrogen, and SN3 performed fine.

On Thursday night SpaceX began cryo-testing the vehicle, which means it was loaded again with nitrogen, but this time it was chilled to flight-like temperatures and put under flight-like pressures. Unfortunately, a little after 2am local time, SN3 failed and began to collapse on top of itself. It appeared as if the vehicle may have lost pressurization and become top-heavy.

Shortly after the failure, SpaceX's founder and chief engineer, Elon Musk, said on Twitter, "We will see what data review says in the morning, but this may have been a test configuration mistake." A testing issue would be good in the sense that it means the vehicle itself performed well, and the problem can be more easily addressed.

This is the third time a Starship has failed during these proof tests that precede engine tests and, potentially flight tests. Multiple sources indicated that had these preliminary tests succeeded, SN3 would have attempted a 150-meter flight test as early as next Tuesday.

Here's a recap of SpaceX's efforts to test full-size Starships to date:

Starship Mk1 : Construction began in December, 2018. Failed during pressure test in November, 2019.

: Construction began in December, 2018. Failed during pressure test in November, 2019. Starship SN1 : Construction began in October, 2019. Failed during a pressure test on Feb. 28.

: Construction began in October, 2019. Failed during a pressure test on Feb. 28. Starship SN2 : Construction began in Feb., 2020. After SN1 failure, was converted into a test bed for thrust puck at base of rocket. Passed test on March 8, and was retired.

: Construction began in Feb., 2020. After SN1 failure, was converted into a test bed for thrust puck at base of rocket. Passed test on March 8, and was retired. Starship SN3 : Construction began in March, 2020. Cryogenic test failure on April 3.

: Construction began in March, 2020. Cryogenic test failure on April 3. Starship SN4: Construction began in March, 2020. Testing begins later this month?

This failure has to be a disappointment in that the prototype rocket failed for a third time before getting to Raptor engine tests. And after the SN1 failure, Musk said he told his engineers, "In the future, you treat that rocket like it’s your baby, and you do not send it to the test site unless you think your baby’s going to be OK."

This baby was not OK.

However, the reality is that SpaceX is now hardware rich, having built up a capacity in South Texas to rapidly build newer and more advanced prototypes of the Starship vehicle. The likelihood of failures is baked into a privately funded program that builds, tests, fails, learns, and then restarts the cycle. So Musk and his engineers will learn from this failure and likely begin to test SN4 later this month.

Listing image by Trevor Mahlmann for Ars