New photos shared by SpaceX show that the company has nearly finished installing a total of 39 upgraded Raptor engines on a new Starship and its Super Heavy booster.
Those prototypes – known as Ship 24 and Booster 7 – could be tasked with supporting Starship’s first orbital launch attempt sometime later this year if both make it through upcoming test campaigns without major issues. Whether that’s a probable outcome is still uncertain but recent progress suggests that it won’t take long for the prospects of both prototypes to shift into clearer focus.
After several rounds of proof testing and two trips to and from SpaceX’s Starbase, Texas orbital launch site (OLS) in March, April, and May, Super Heavy Booster 7 (B7) made its third trip to the pad on June 23rd.
“SpaceX used the six weeks Booster 7 spent back in a factory assembly bay to finish installing aerocovers, surfaces known as chines or strakes, car-sized grid fins, Starlink internet dishes, and – most importantly – 33 upgraded Raptor V2 engines. Combined, Booster 7 could produce up to 7600 metric tons (~16.8M lbf) of thrust at or before liftoff. Crucially, SpaceX also finished installing most of Booster 7’s Raptor heat shield in the same period, completing in six weeks work that took Booster 4 closer to half a year. With its heat shield and all 33 Raptors mostly in place, Booster 7 should be ready to kick off static fire testing almost as soon as it’s installed on Starbase’s orbital launch mount.”
Teslarati.com – June 24th, 2022
Building, qualifying, shipping, and installing 33 new Raptor 2 engines on Super Heavy B7 was already an impressive achievement and produced the most (potentially) powerful rocket booster ever assembled. On July 2nd, a pair of photos published by SpaceX showed off Booster 7’s nearly-finished engine section and simultaneously revealed that the company has finished installing all six of Starship S24’s Raptor engines – and even part of the ship’s aft thermal protection.
Differences are already visible between Ship 24 and Ship 20, the only other Starship prototype to have six Raptors installed. The most notable change is the addition of a metal framework that covers the entire breadth of the ship’s aft – most likely intended to support flat sections of insulation and thermal protection that will partially seal off sensitive engine, plumbing, pressure vessels, and avionics components located inside Starship’s aft. That extra shielding should help limit the extreme conditions that hardware will be subjected to during ground testing and, perhaps, in flight.
Super Heavy Booster 7 has already completed a significant amount of testing, including four cryogenic proofs (cryoproofs) and one Raptor thrust simulation test. Since its third return to the pad, SpaceX has several more ambiguous tests, none of which appeared to involve cryogenic propellant loading. It’s possible that those tests focused more on Booster 7’s pressurization system, perhaps filling its tanks with the hot oxygen and methane gases it will eventually use to pressurize its tanks. It’s likely that SpaceX wants to put Booster 7 through at least one successful wet dress rehearsal – using real liquid methane and oxygen propellant – before attempting to static fire any of its 33 Raptors. Booster 7’s aft thermal protection system also isn’t entirely complete, so technicians will need to finish installing several more panels before any static fire testing.
Alongside B7, Starship S24 has completed a good amount of cryoproof and Raptor thrust simulation testing, which it survived without any irreperable issues. The ship was then returned to an assembly bay on June 9th, where where workers have been installing heat shield tiles, finalizing the ship’s engine section, and completing dozens of other less visible closeout tasks. SpaceX also recently finished modifying one of its two suborbital test and launch mounts for Starship static fire testing, leaving the other mount semi-permanently modified for cryoproof and thrust simulation testing of future prototypes.
SpaceX has requested permission for road closures – each a potential 12-hour test window – on July 5th, 6th, 7th, 11th, and 12th.