SpaceX has apparently decided to reuse a large section of a Starship prototype that was accidentally destroyed during testing earlier this month, a first for the next-generation rocket.
While not quite the same kind of ‘reuse’ SpaceX has largely pioneered with its vertically-landing Falcon rocket boosters, the company’s decision to reuse an unflown section of a former Starship prototype is yet another sign of its prioritization of efficiency and speed. The Starship SN3 hardware SpaceX has chosen to repurpose on Starship SN4 is relatively straightforward relative to almost all other sections of the newest prototype, but it should still save the company a not-insignificant amount of time and money.
For SpaceX, a combination of extraordinary speed and efficiency at its nascent South Texas Starship factory is allowing the company to accomplish feats that would otherwise be impossible. At least as important, fast and cheap Starship manufacturing has meant that SpaceX is far more willing (perhaps even a little too willing) to take risks with any given prototype, partly explaining why the company is about to complete its fourth full-scale Starship in as many months.
A few days after Starship SN3 was destroyed by some combination of operator error and a badly-designed test, CEO Elon Musk confirmed suspicions that part of the rocket – appearing effectively unscathed – could be reused on the next prototype.
Speaking on April 5th, Musk actually indicated that “much” of Starship SN3’s thrust section could be reused, referring to roughly the bottom third of the rocket’s tank section. Located at the aft (rear) end of Starship, the engine section is where 3-6 Raptor engines attach to the rocket and must safely transfer their thrust through the rest of the vehicle while also feeding those engines propellant and redistributing high-pressure gases to the ship’s main tanks. As a result, engine sections are often some of the most complex and labor-intensive parts of rocket production.
It appears that Musk wound up being partially correct with his initial judgement. On April 15th, eight days after Starship SN3’s remaining aft section was cut in half, the rearmost half – known as the skirt – was spotted stacked beneath a brand new engine section built for SN4. While confirming that a significant part of SN3 will be reused on SN4, it also indicates that only a less critical SN3 remnant was fit to join SpaceX’s next prototype.
Recently confirmed by Musk after a Teslarati article on the topic, Starship SN3’s skirt section – while not the more complex engine section and thrust structure – has been fitted with six landing legs in anticipation of the first full-scale Starship flight tests.
Aside from landing legs, the reused SN3 skirt also includes substantial structural reinforcements, ground umbilical connections for propellant, power, and telemetry, and built-in hold-down clamps. While fairly small in the scope of an entire Starship, SN4’s adoption of SN3’s skirt should help speed the new rocket towards completion and the start of its first test campaign. Barring surprises, SpaceX will almost certainly move Starship SN4 to its nearby testing facilities within the next several days to a week.