SpaceX continues with the Starship pace, with another busy week involving the reveal and first firing of the Raptor 3 engine, a spin prime — and not a static fire — for Ship 30, tons more Orbital Launch Pad B work. SpaceX noted it is also working Flight 6 preparations while waiting for Flight 5 regulatory approval, which ups the milestones with a potential catch by the Tower’s Mechazilla chopsticks. Preparing for that goal is B14.1, out at Orbital Launch Pad A for more slap testing.
Ship 33
Ship 33 continues to be stacked, as only two sections remain until the first Block 2 ship is fully assembled. Those sections are the bottom Liquid Oxygen Tank section, slated to have four rings, and the aft engine section, which also has four rings. This will bring the number of rings for Block 2 Starships to 21, compared to 20 on Block 1 ships.
This extra ring and the ability to move the tanks allow SpaceX to add around 300 tons of extra propellant to the vehicle.
Production Site with Ship 31 in High Bay and Ship 33 in Mega Bay 2 (Credit: Jack Beyer for NSF/L2)
Raptor 3
Recently, SpaceX revealed pictures and specifications of Raptor 3, which is slated to replace the current Raptor 2 on current vehicles. This engine is far more refined, with much of the external plumbing moved internally or removed altogether. A lot of the internal plumbing is regenerative cooling channels built into the engine’s case.
This allows SpaceX to run the engine with more pressure and eliminate the heavy heat shield currently used on Raptor 2.
Raptor 2 number 164 before install on Ship 28 (Credit: Jack Beyer for NSF/L2)
Raptor 1 was used on the suborbital test flights and vehicles up to Booster 4 and Ship 20. This engine was still very much a prototype engine. It only had 185 metric tons of thrust and weighed a decent amount, with the engine being 2,080 kg and 3,630 kg when all vehicle-side commodities and hardware were added on.
Raptor 2 has been used since Booster 7 and Ship 24. So far, it has been the Starship program’s most produced engine, with at least 569 engines made and possibly a decent amount more. This engine runs at 230 metric tons of thrust and is much lighter than Raptor 1. The engine itself is 1,630 kg, and added vehicle-side committees and hardware bring it to 2,875 kg.
Performance stats of previous versions:
Raptor 1 (sea level variant)
Thrust: 185tf
Specific impulse: 350s
Engine mass: 2080kg
Engine + vehicle-side commodities and hardware mass: 3630kgRaptor 2 (sea level variant)
Thrust: 230tf
Specific impulse: 347s
Engine mass: 1630kg
Engine… pic.twitter.com/8PgQeALOx4— SpaceX (@SpaceX) August 3, 2024
Now, Raptor 2 got Starship into space and has been very reliable during launches, with only a couple of failures on Flight 1 and two on Flight 4.
Then comes Raptor 3, which, based on pictures from SpaceX, is in the East bay of the Raptor Vertical test stand at McGregor, Texas. This engine is slated to have 280 metric tons of thrust and drastically reduce the weight needed to support it. The engine is slated to be 1,525 kg and, with added vehicle-side components, 1,720 kg.
30 second test on the vertical test stand at the SpaceX McGregor test site, we believe this is the first test of the Raptor 3 engine. @NASASpaceflight
McGregor Live 24/7 https://t.co/m2zcSH8zdh pic.twitter.com/GlUnQ7AU8Y— Elisar Priel (@ENNEPS) August 8, 2024
As stated before, SpaceX can make it much lighter by removing heat shields. Looking at Raptor 3, it looks to be in two separate parts: a low-pressure side that still has flanges and seals and a high-pressure side on the bottom with no flanges. Removing flanges and those seals will allow SpaceX to run the engine at higher and higher pressures, which results in more thrust coming out of the engine.
It is unclear when this engine will be placed on a vehicle. SpaceX probably still needs more testing now that the design is somewhat finalized. As an added bonus, SpaceX Chief Operating Officer Gwynne Shotwell treated everyone to an amazing picture of Raptor 3 SN1 Static fire at McGregor.
Works pretty good for a “partially assembled” engine 🙂 pic.twitter.com/UkHkGyoOY7
— Gwynne Shotwell (@Gwynne_Shotwell) August 8, 2024
Flight 5 and 6 news
Ship 30 did more engine testing this past week with a spin prime. This was required if another Raptort Vacuum Engine was swapped out, and R398 was swapped for R384. It is unknown why SpaceX swapped this engine out.
This time around, teams only completed a spin prime, as happened with Ship 28 after one of its Raptor Vacuum engines was swapped.
Ship 30 at Masseys Flame Trench (Credit: Jack Beyer for NSF/L2)
Ship 30 is back at the production site and on a ship transport stand. This ship should be getting its final touches, barring another engine change. Teams will finish the heat shield work and other final line items until Orbital Launch Pad A becomes available. Once out at the pad, Booster 12 and Ship 30 can complete a Wet Dress Rehearsal; however, it is unknown when or even if this will happen or how close to launch such a thing will be.
Regarding the readiness for Flight 5, SpaceX posted on social media that both Flight 5 vehicles are ready pending regulatory approval. This follows the just-completed spin prime Ship 30. Both Ship 30 and Booster 12 could be ready, but in the past, SpaceX has said this when, in fact, neither vehicle was actually ready for flight.
SpaceX also started to catch testing, and Flight 6 vehicle testing would occur while crews waited for approval. B14.1 is back at the Orbital Launch Mount (OLM) for said catch testing. However, Flight 6’s vehicles are occupied a bit at the moment.
Flight 5 Starship and Super Heavy are ready to fly, pending regulatory approval. Additional booster catch testing and Flight 6 vehicle testing is planned while waiting for clearance to fly pic.twitter.com/FFoGPEtztI
— SpaceX (@SpaceX) August 8, 2024
Ship 31 just recently started getting its heat shield redone, like SpaceX did to Ship 30, which took about 38 days to complete. So, Ship 31 will be tied up in the High Bay tiling station for the foreseeable future.
As for Ship 31’s other half, Booster 13 has been on the center Mega Bay 1 work stand since finishing its cryogenic proof testing at the end of April. Teams currently have a tent built up on the forward dome of Booster 13, which alludes to possibly some major work with that booster. Also, Booster 13 still doesn’t have its grid fins.
Booster 13 With work on its Forward Dome (Credit: BocaChicaGal for NSF/L2)
There is no firm launch date for Flight 5 at this time.
Orbital Launch Pad B
Orbital Launch Pad B continues progressing, as the tower is now six modules tall. With the first six modules done, the CC8800-1 was laid down and is currently finishing its reconfiguration before being raised again to finish the tower. Modules 7, 8, and 9 have scaffolding on top and look to be ready for rollout and installation as soon as the crane is ready once again.
During this downtime, crews have been finishing up the welding around the tower base and then filling the hollow walls with concrete, which will add even more strength to the tower.
Crews are still driving sheet piles into the ground around a suspected flame trench. The new Teired Environmental Assessment proposal, released recently, provided more proof. However, it will still be several months before we see exactly what shape this structure will take.
Orbital Launch Pad B (Credit: Jack Beyer for NSF/L2)
B14.1 The Slappening Part Deux Electric Boogaloo
Booster 14.1 was rolled back out to Orbital Launch Pad A ahead of what is assumed to be chopstick catch testing. At the end of June, B14.1 was mounted on the OLM and “slapped” by the chopsticks. This testing was to dial in the speed and control of the chopstick arms before a flight booster came in for a landing.
Teams also tested the landing rail system to ensure that the system could take the instant load required.
Since those tests, SpaceX has replaced many of the linkages to the landing rails on both arms and upgraded and added more landing rail actuators to both arms. This will help the rails take more force and be more controllable. Another big change is that teams are replacing and upgrading the bumper pads used to slap B14.1 in June.
Orbital Launch Pad A with B14.1 (Credit: Jack Beyer for NSF/L2)
While teams had replaced the actuator on the north side arm, crews only upgraded the main actuator on the south arm. So, both arms should be able to move at full speed once these changes are completed.
With all these changes, teams might do a clap test, which would be both arms coming in for a slap simultaneously, simulating a catch. The one other major thing SpaceX did not do during the last round of testing was slap and then bring up the arm in one full motion.
B14.1 on the OLM (Credit: BocaChicaGal for NSF/L2)
SpaceX continues to push ahead to Flight 5 while working on the next launch at Starbase and flight.
Featured Image: Orbital Launch Site with two Towers (Credit: BocaChicaGal for NSF/L2)
