Thread by @Ringwatchers

As SpaceX prepares to structurally qualify its new interstage design, intended to be used for hot staging, let’s look at the new parts that will be used for this, and what we can learn from these new parts. (1/12)

The test article at the Massey’s testing site is labelled the “Hot Stage Load Head”, and will be used to qualify the interstage against the aerodynamic forces it will experience during flight. There are 3 main components to this. (2/12)

🖼️ @ChameleonCir

The bottom barrel section is the old Booster 11 forward dome section that was reassigned to become a test article for this, seemingly back in January of this year, possibly suggesting when this design decision was made. (3/12)

📸 @RGVaerialphotos

It wasn’t worked on for some time, until it moved into Tent 1 on July 6th, and later came back out with extra stringers. It’s important to note that these stringers should just be for the test article, overbuilding that part that is irrelevant to the test. (4/12)

📸 @LabPadre

2 hot staging vent rings were seen before this article here. The first was spotted on May 25th, and a revised design was spotted on July 20th. The one on this Booster forward dome, however, is the first to be seen with reinforcements. (5/12)

📸 @LabPadre @StarshipGazer

The vertical supports have triangular stringers on the inside, which add critical support to the ring and should also help direct the exhaust out. There is also diagonal bracing in some areas to help support against torsion forces. (6/12)

📸 @thejackbeyer
🖼️ @ChameleonCir

There is also a large hoop stiffener passing through the middle of this section, which has a band welded to it on the inside, adding additional strength. Doubler plating, increasing the steel thickness, can also be found in various places. (7/12)

📸 @thejackbeyer

It does seem that this will be attached using the staging clamps, as the housings for them were developed on the Booster forward. Currently, they are only chained together, likely because a real clamping system isn't necessary for this test. (8/12)

📸 @thejackbeyer @LabPadre

The vent areas are not evenly spaced, however. There are larger vertical gaps where the 3 staging clamps are, which makes it so this is essentially 3 pairs of vent areas. This also makes it so that each pair is near an RVac engine, which is good. (9/12)

📸 @NASASpaceflight

The top is the old leg skirt from Ship 26.1. This was cut off of the test tank a few months ago and returned to the Production Site to receive more stringers. Just like the Booster forward, this is just overbuilding the irrelevant areas. (10/12)

📸 @RGVaerialphotos @LabPadre

This is almost identical to the interstage testing done with Booster 6 at the end of 2022, where an almost identical leg skirt was used to pull down on top. Essentially this is pressing down with the Ship connection, providing more accurate info. (11/12)

📸 @RGVaerialphotos

When they are eventually assembled on the Can Crusher stand, we’ll be looking at something like this. We can only hope that it passes testing successfully, and maybe we’ll see one of these integrated with Booster 9 in the not-too-distant future. (12/12)

🖼️ @ChameleonCir