Update: Commenting on this article, SpaceX CEO Elon Musk says the plan is to not only cryoproof the first airworthy Super Heavy, but also fire the booster statically and launch Starship’s brand new orbital launch complex as early as next. “next week” to shake off.
A lot of work would have to be completed – and everything smoothly – for a cryo-resistant orbital launch pad and static fire possible in just a week or less, but Musk’s response nonetheless provides invaluable context for SpaceX’s short-term plans and confirms that Super Heavy Booster 4 is ready for integrated testing as is. Furthermore, Musk’s tweet – as speculated – implies that the tank farm of Starbase’s orbital launch complex is much closer to test readiness than it would otherwise appear.
For the second time in five weeks, SpaceX has installed a Super Heavy booster — equipped with 29 Raptor engines — on Starship’s nascent “orbital launch mount.”
Both Super Heavy Booster 4 (B4) and the launch prop have undergone significant changes since they last broke up four weeks ago. SpaceX teams are laser focused on installing the vast array of plumbing, wiring and components needed to convert the hulking steel structures into functional launch facilities and the largest flyworthy rocket and both certainly look the part.
Super Heavy Booster 4 pic.twitter.com/jQ7RAN1nCK
— SPAdre (@SpacePadreIsle) September 8, 2021
Unlike Starship, which has an expansive skirt section that’s perfect for storing sensitive plumbing and avionics, Super Heavy has an unusually short intermediate stage and no real skirt, meaning all the extra hardware SpaceX has installed over the past month or so is impossible. is to hide. Indeed, when Booster 4 rolled out of Starbase’s high space for the second time on Sept. 8, the rocket was covered with dozens of new valves, thousands of feet of wiring and plumbing, pressure vessels, multiple hydraulic racks, a ‘quick disconnect’ (QD) umbilical cord panel. for interface with the launch pad, sites for installing explosives with a “flight termination system” (FTS) and much, much more.
In addition, Super Heavy B4s second batch of 29 Raptors — installed in late August — also all appear to have outward-facing umbilical cord panels that will all be the booster to get some level of help from ground systems as those engines fire up. It’s unclear what exactly they’ll do, but it’s likely that engine power cable will be hooked up to high-pressure gas systems on the ground, minimizing the already absurd amount of COPVs and secondary plumbing present on Super Heavy.
However, Super Heavy still needs to be able to re-ignite 1 to 13 of its 29-32 Raptor engines in flight for boostback and landing burns, which could possibly explain the eight major pressure vessels and 100+ small high-pressure gas lines. on the back of B4. Super Heavy must also be able to cool, power and purge all 29-32 of its Raptor engines, guaranteeing that the situation with Starship’s booster pipes would be hugely complex, regardless of the approach SpaceX took.
In addition to the newfound complexity of Super Heavy B4, SpaceX has also spent the last four weeks or so equipping Starbase’s orbital launch mount with all the plumbing, power, avionics, and mechanical systems it needs to function as “Stage Zero.” orbital-class, two-stage spaceship missiles. SpaceX has installed most of the secondary shortcut structures that connect and feed each of Super Heavy’s 20 outer Raptor engines. The main Super Heavy quick coupler device has also been installed and a team has gradually equipped the structure and connected it to the plumbing, avionics and power supply that will supply the boosters.
Significant work remains to connect the orbital launch assembly to SpaceX’s incomplete and custom orbital tank farm, which will store, supercool and feed the pad, Super Heavy and Starship with several thousand metric tons of liquid and gaseous oxygen and methane. . It’s hard to tell how close Starbase’s tank farm is to supporting Starship or Super Heavy testing, making it equally unclear what SpaceX’s short-term plans are for Booster 4. It’s possible the rocket was reinstalled on the orbital launch mount as a second fit check, perhaps targeting those 20 outer Raptor quick-release mechanisms.
It’s also possible that the tank farm and launcher are much closer to completion than expected, meaning Super Heavy B4 could remain on the orbital path until several critical cryogenic evidence and static fire tests are completed. Of course, aside from confirmation from Musk himself, we’ll just have to wait and see.