SpaceX is gearing up for Flight 4. The start of full stack testing on Thursday resulted in a partial load of propellants, which will be followed by a full Wet Dress Rerhasal in the coming days. In tandem with preparation for the next flight, SpaceX is making progress on its future ambitions with a second tower being prepared at Starbase, while information has come to light on SpaceX’s 39A Starship pad in Florida.

Flight 4 Wet Dress Rehearsal 

SpaceX rolled out both vehicles for Flight 4 of Starship and stacked them on the Orbital Launch Mount (OLM) ahead of full-stack testing. So far, both Booster 11 and Ship 29 have completed their individual test campaigns and have completed a partial load tanking test on May 16, with a possibility of a Wet Dress Rehearsal (WDR) as early as Saturday, May 18.

A WDR is when the vehicle is fully loaded with propellant and put through a simulated launch countdown for testing purposes. For Starship, this means loading all tanks to flight levels with Liquid Methane (LCH4) and Liquid Oxygen (LOX).

Starship Flight 4 Full Stack Tanking Test (Partial/Mini-WDR – Wet Dress Rehearsal) appears to have gone well. Partial load achieved and now detanking.

— Chris Bergin – NSF (@NASASpaceflight) May 16, 2024

SpaceX has conducted a WDR for each of the first three flights of Starship to this point, with constant changes to the Orbital Launch Pad (OLP) between each flight. Between Flight 3 and Flight 4, SpaceX has completely shifted to the horizontal Liquid Nitrogen (LN2) and LOX tanks and has already started vacuuming out the perlite in old vertical LOX tanks.
Following such changes, SpaceX is expected to test how the Orbital Tank Farm operates using the new lines and tanks in a launch configuration before an actual launch day.

Teams will also want to test the tank pressurization setup as they load into a set of vehicles rather than just venting out of the Orbital Launch Mount (OLM) and the Orbital Launch Integration Tower (OLIT).

Orbital Launch Pad A (Credit: Jack Beyer for NSF)

SpaceX performed a partial load test before moving to a full WDR to help verify the systems with vehicles on the pad before fully loading Methane and LOX into the stack.

Documentation, such as the Marine Safety Information Bulletin, warns ships to avoid the area around the OLP. This currently projects a full WDR on Saturday.

Once the WDR is completed, SpaceX will most likely roll back Ship 29 as there is still more work to be completed on its heat shield.  SpaceX may also take the opportunity to inspect the vehicle for any potential commonality issues related to the anomaly with Ship 31 at Masseys.

Ship 29 being stacked on Booster 11 (Credit: Mary/BocaChicaGal)

Ship 30 and Goodbye Pad B

Since rolling out last week, Ship 30 has completed a small cryogenic proof test, an aborted static fire, and a six-engine static fire. This makes Ship 30 the first orbital-class ship to skip a spin prime or preburner before a static fire. SpaceX may be comfortable doing this because Ship 30 had its engines installed on the new enclosed work stand.

With these new stands, SpaceX can control the environment in which the engines are installed and prevent Foreign Object Debris (FOD) from getting into pipes and connections. These also allow teams to use specific tooling to install the engines, thus making the installation more accurate and safer.

Ship 30 will not perform a single-engine static fire, like Ship 28 and Ship 29, since it has already been removed from Pad B and rolled back to the High Bay.

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Ship 30 was positioned in the High Bay’s tiling station before moving to the back of the bay. However, crews will need to spend several weeks fixing its heat shield as SpaceX wants to ensure that this ship stands the best chance for successful reentry.

With this engine test campaign complete and Suborbital Pad B already nearly gone, this marks the end for the Suborbital side of the Launch Site.

The tank farm and its two pads were pivotal to the Starship program’s current state, helping fly Starhopper and all of the early SN prototypes, culminating in SN15 completing a successful landing.

(Starhopper, SN7.2, SN9, and SN10 sitting at the launch site. Credit: SpaceX)

The site was then shifted to cryogenic proof and static fire testing for orbital-class Starships, which ended with Ship 30. On the bright side, Suborbital Pad B will be upgraded to Orbital Pad B, which will further the Starship program.


SpaceX has been quickly building a new ship Static Fire Stand and flame trench at Masseys for the last several months.

Ship 26 was recently placed on the new mobile stand and rolled over the new flame trench to perform fit checks and possibly some cryogenic testing. SpaceX is using Ship 26 rather than a flight vehicle so that if something were to break, there wouldn’t be any impact to the flight program.

Masseys Test Site (Credit: Jack Beyer for NSF)

Along with Ship 26, Ship 31 is also at Masseys to perform its cryogenic proof testing. Ship 31’s other half, which is assumed to be Booster 13, just recently completed its own cryogenic proof testing and should begin getting engines in Mega Bay 1. These two vehicles are slated to fly on Flight 6, which may not be far away.

Ship 31 suffered an anomaly while completing a cryogenic proof test at Masseys to verify the tanks’ construction. Several bright flashes of light and smoke were on the raceway going up the rocket. The raceway is where all the data and power lines run from the engine section to the avionics in the payload bay right next to the forward dome.

Ship 31 appears to have suffered an issue during its cryo testing at Masseys.

— Chris Bergin – NSF (@NASASpaceflight) May 13, 2024

This was most likely an electrical short that caused arcing, which damaged Ship 31’s raceway. SpaceX has since rolled this vehicle back to the High Bay and will do inspections to see if any more systems onboard were damaged. If SpaceX suspects this could be an issue with other ships, then teams will do inspections; however, it could be an isolated incident.

Orbital Launch Pad B

SpaceX continues to make progress on Orbital Pad B, with more pilings being installed and the crews already starting to dismantle Suborbital Pad B and the Suborbital Tank Farm itself. A new development is that SpaceX intends to roll all five tower sections from the Port of Brownsville to Sanchez. In fact, teams already rolled Section (X) to Sanchez.

The rollout closures for these moves are 10 pm to 2 am on May 13, 15, 17,19, and 20. Once these tower sections are in the Sanchez Site SpaceX will begin to add all of the cryogenic lines and other internals that can be added before the sections get stacked.

Teams have already rolled section 7 to the Sanchez Site with sections 1, 2, 3, and 6 at the Port of Brownsville with sections 8 and 9 at the Sanchez Site, and sections 4 and 5 still at Roberts Road at Cape Canaveral.

Orbital Launch Pad B (Credit: Jack Beyer for NSF)

According to an FAA document for the proposal of Starbase Integration Tower 2, the tower is to be located in the square of pilings that have been drilled in the picture above.

Environmental Impact Statement for LC-39A Starship

SpaceX has applied for a revised Environmental Impact Statement (EIS) regarding Starship Operations at LC-39A. The FAA and SpaceX had already completed an EIS back in 2019. However, the Starship program has changed so much since then, with launch pad and vehicle changes alike, that SpaceX is required to complete another EIS to perform Starship operations at LC-39A.

An EIS is a study of the environmental impacts a system will have on the environment around it, such as sound waves, pollution, threats to wildlife, and many other factors considered in these reports. Collecting all of this data usually takes over a year or more to study the environment of the proposed action and its potential impacts. 

Proposal for LC-39A Environmental Impact Statement (Credit:

The proposed action in this EIS would give SpaceX an operator’s license to fly Starship from LC-39A based on the scope of the proposed action. This proposed action consists of the totality of the Starship Program’s infrastructure improvements and operations and includes the ones identified in the 2019 EA for Starship. 

SpaceX has applied to have up to 44 Starship launches per year, which can be during the day or night. These launches would include a Starship or Booster landing back at the launch site, landing downrange on a droneship, or expended in the Atlantic Ocean. With these Starship operations, SpaceX would also continue Falcon 9 and Falcon Heavy operations alongside LC-39A.

LC-39A with Starship Pad work ongoing (Credit: Julia Bergeron for NSF/L2)

While there are infrastructure improvements that are consistent with the 2019 EA already being built, SpaceX proposed additional improvements to LC-39A in this EIS. These include on-site propellant production and storage and a deluge for the launch pad. The propellant production would include things like an air separation, as seen at the Sanchez site before SpaceX demolished it.

Along with the proposed action, there is an alternative action based on this EIS that can provide the National Aeronautics and Space Administration (NASA) and commercial partners with access to Starship, which is a critical path to NASA’s Artemis program. Given these reasons, the only alternative according to the proposal would be a no-action alternative. Under this alternative, SpaceX would not receive a vehicle operator’s license, and further improvements to LC-39A wouldn’t continue.

Overall, this means SpaceX will have to wait to launch from LC-39A until this EIS is completed and they are issued a vehicle operator license. This isn’t a bad thing; with this completed, SpaceX will have a much stronger presence and infrastructure at pad LC-39A for Starship launches in the future.

Featured Image: Ship 29 stacked on Booster 11 for the first time (Credit: Jack Beyer for NSF)

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