SpaceX recently installed the new hot staging ring atop Booster 9 that will attempt this new stage separation method.
The hot staging ring has gone through its own test campaign, including being connected to the “can crusher,” which simulates stresses on the rocket during liftoff and, having passed that test, was then installed.
Hot staging is when the 2nd stage, in this case, Starship, ignites its engines while still connected to then pull away from Booster 9, which will also still be firing some of its own engines but with those throttled down. The hot staging method isn’t a new idea, as it has been used by Russian rockets for years now and also by older American rockets such as the Titan II.
The ring features mostly vents on the sides and a stainless steel dome, but underneath is heavily reinforced in order to withstand the forces from the Raptor engines firing above it during hot staging.
SpaceX has yet to confirm which of the Starship Raptor engines will ignite first, but with the sea level (3 center) Raptor engines sitting extremely close to the top of the dome, it wouldn’t be surprising if the outer three vacuum Raptors ignited first followed by the three center engines shortly after.
Back at the launch site, the Starship quick disconnect arm that’s used to fuel Starship has already been adjusted and raised higher to account for the addition of the hot stage ring.
No matter which way they ignite engines, it’ll certainly be an insane view if the rocket makes it to the staging phase of flight, which will be expected.
SpaceX also recently shared a video from their McGregor Test Facility showing a Raptor engine firing while gimbaling 15 degrees. Elon Musk said that it was to simulate the landing burn at “max gimbal deflection.”
Long duration test fire of Raptor while gimbaled 15 degrees pic.twitter.com/HuYqmtE8fc
— SpaceX (@SpaceX) August 17, 2023
At the production site, the company recently demolished one of the production tents and started taking down the mid-bay to make room for a new improved production facility after recently demolishing the windbreak that had been standing since the early days of Starbase.
Booster 9 is expected to head back to the Orbital Launch Mount sometime this week. However, the tropics are picking up, which may force SpaceX to keep it safe in the high bay until the path of the storms is clearer.