Musk Confirms Starship Orbital Launch with Raptor 2 Engine, Sets May Timeline
The first orbital flight of Starship will be powered by the new Raptor 2 engines, Elon Musk confirmed today via tweet.
Musk details that the orbital test will tentatively be set around May as the new Raptor 2 engines are integrated into the Super Heavy booster and Starship.
The latest Super Heavy Booster tested was Booster 4, with a configuration of 29 Raptor V1 engines. On March 16th, Booster 4 and Starship S20 were married via the Mechazilla armature, and a full stack cryo proofing was successful. Given that we now know SpaceX is moving ahead with the goal of using Raptor 2 on its orbital test articles, this test was more likely to see if the Super Heavy Boosters could take the weight of a partially loaded Starship, to check the plumbing, and to test Mechazilla’s capabilities. More testing on this combination of vehicles is expected throughout the next week or two.
So then, what changes will have to happen for the introduction of Raptor 2? Well, from the testing specs, it seems as though SpaceX knew Raptor V1 wasn’t going to be enough to push Starship into orbit without some serious redesigns. That said, the COPV (Composite Overwrapped Pressure Vessel) tanks have already been repositioned to vertical rows along the body instead of surrounding the base, likely to accommodate the Raptor 2 gimbals needing to be mounted on the vehicle instead of being integral to the engine.
Some recent Starship design changes are also likely being done to accommodate more fuel for extra engines, and offset the extra weight. The nose cone design has changed to leave room for a methane header tank, and the remaining structure has added more rings closer together to keep structural stability. Super Heavy Boosters are reportedly also getting extra rings to support its aft dome sleeve, making four rings at 4’6” high, rather than the previous three ring setup at 6’ high.
But the crux of the problem was really with the Raptor Vacuum engines on Starship being able to push orbital insertion. According to Musk, Starship orbital insertion will require burns of about 5.5-6.5 minutes long. Hard to do with the current Raptor V1 engines, but much better odds with the V2. Musk hasn’t mentioned if the Vac engines will be brought into line with Raptor 2 specs, but the difference is now 6 current Raptor Vacs on the ship, in addition to 3 Raptor 2s.
Regardless of what gets put onto Starship, the new configuration of 33 Raptor 2 engines on the Super Heavy Booster will certainly add to the ΔV, and help get Starship into a better position for orbital insertion. And considering Elon was already talking about expanding the Raptor V1 configurations from 29 to maybe 33 engines previously; getting the more compact and efficient V2 to fit the same space with more engines shouldn’t be too difficult.
But are there perhaps already test vehicles waiting in the wings for this orbital test? Well the best guess on Boosters is likely Boosters 8 and 9; as Booster 8 is receiving some new booster upgrades and methane manifold configurations.
And as for likely Starship candidates, S24 not only has a payload door for testing, but it also has a 6 RVac configuration, which lines up with the previous thoughts on the need for 6 engines for orbital insertion.
Anyhow, speculation won’t be needed for long. An attempted orbital test slated for May is going to mean much more details being released in the coming months. Stay tuned.