For the first time in more than half a year, SpaceX has stacked a new Starship prototype to its full height, hopefully marking the end of a period of relatively slow progress.

That period began when Starship S20 was stacked to its full height in early August 2021. Until very recently, Ship 20 was said and expected to be the prototype assigned to Starship’s first orbital test flight, making it exceptionally important. In an unusual change in attitude, SpaceX may have felt the same, which may explain why Starship S20’s first static fire test took place more than two months after it first left the factory. A year prior, Starships SN9, SN10, SN11, and SN15 all completed proof testing a matter of weeks after rollout.

That sudden change of pace relative to past development has meant that Ship 20 is the only Starship prototype SpaceX has tested since May 2021 and the only Starship to graduate from final assembly to testing in the last six months. In that period, Ship 20 has completed a few major cryogenic proof tests and four static fires – two of which ignited all six Raptor engines. While Ship 20’s six-engine tests were unprecedented and marked a major program milestone, SpaceX once static-fired Starship SN9 three times in one day in January 2021.

However, that period of sluggish prototype testing may finally be coming to an end. In August 2021, when SpaceX stacked Starship S20 and Super Heavy B4 for the first time, the general assumption was that the seemingly imminent march towards orbital flight testing would be similar to SpaceX’s attempts to land a Starship from medium altitude between December 2020 and May 2021 – lots of prototypes in flow and multiple back-to-back tests and launches, in other words. That was not the case.

Starship S21, for example, began final assembly in mid-October 2021 and its tank section and nose section were both fully stacked less than a month later. However, rather than stack them into a second complete ship, SpaceX has left those separate assemblies sitting around Starbase for the last three months. Simultaneously, while Ship 21’s apparent limbo seemed to imply that SpaceX was implementing another block upgrade and moving on to newer prototypes, the company actually started stacking Starship S22 about a week after S21’s separate sections were completed. Only three months later have SpaceX’s plans for those three sections finally become clear.

On February 14th, 2022, Ship 22’s tank section followed Ship 21’s nose section into Starbase’s high bay assembly facility, where they were quickly stacked to form a full Starship prototype the same day. This raises the question: why?

Given that Starship S20 effectively completed qualification testing with three successful static fires in December 2021 and a fourth in early January 2022 and has been seemingly ready to fly ever since, its Super Heavy booster readiness – not ship readiness – that appears to be holding SpaceX back. Perhaps because of pad readiness issues, SpaceX has yet to perform a single Super Heavy static fire test – or even a less risky wet dress rehearsal – at the orbital launch site. As such, it’s hard to say why SpaceX has suddenly decided to finish Ship 22 instead of focusing on a newer version of Starship (S24) and Super Heavy (B7) – both of which are expected to debut upgrades.

It’s possible that Ship 22 is being completed merely as practice for the Starbase workforce, who have gone half a year without fully assembling another ship prototype, but then there would have been no reason not to install Ship 21’s nose on Ship 21’s tank section instead of withholding it for Ship 22. Ship 22 could also be a replacement for Ship 21 if appearances are misleading and SpaceX uncovered issues with the older prototype during testing but again, no booster is ready to launch either ship.

Regardless of the outcome or purpose of Ship 22, seeing any new Starship prototype completed is an exciting and interesting change of pace after half a year of following the windy paths of Ship 20, Booster 5, and Ship 21 to their uncertain goals.