Starship Flight 4 Begins Wet Dress Rehearsal Campaign – NASASpaceFlight.com

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SpaceX is gearing up for Flight 4. The start of full-stack testing on Thursday resulted in a partial propellant load, which will be followed by a full Wet Dress Rerhasal in the coming days. In addition to preparing 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 platform in Florida.

Flight 4 wet clothing rehearsal

SpaceX deployed both vehicles for Starship Flight 4 and stacked them on the Orbital Launch Mount (OLM) prior to full-stack testing. To date, both Booster 11 and Ship 29 have completed their individual test campaigns, completing a partial load tank test on May 16, with the 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 performs a simulated launch countdown for testing purposes. For Starship, this means that all tanks are charged to flight level with liquid methane (LCH4) and liquid oxygen (LOX).

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

Teams will also want to test the tank pressure setup while loading into a series of vehicles, rather than just venting from the Orbital Launch Mount (OLM) and the Orbital Launch Integration Tower (OLIT).

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

SpaceX conducted a partial load test before moving to a full WDR to help verify the systems with vehicles on the path 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 complete, SpaceX will most likely turn ship 29 back as more heat shield work needs to be completed. SpaceX may also take the opportunity to inspect the vehicle for potential commonality issues related to the ship 31 anomaly at Masseys.

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

Ship 30 and goodbye Pad B

Since deploying last week, Ship 30 has completed a small cryogenic 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 feel comfortable here because Ship 30’s engines were installed on the new enclosed working stand.

These new stands allow SpaceX to monitor the environment in which the engines are installed and prevent Foreign Object Debris (FOD) from entering pipes and connections. This also allows teams to use specific tools to install the engines, making the installation more precise and safer.

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

Ship 30 was placed in the High Bay tiling station before moving to the back of the bay. However, crews will need several weeks to repair the heat shield as SpaceX wants to ensure this ship has the best chance of a successful return.

With this engine test campaign complete and Suborbital Pad B almost gone, this marks the end for the Suborbital side of the launch site.

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

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

The site then moved to cryogenic and static fire testing for orbital-class starships, ending with Ship 30. On the plus side, Suborbital Pad B will be upgraded to Orbital Pad B, furthering the Starship program.

Massey’s

SpaceX has quickly built a new ship Static Fire Stand and flame trench at Masseys in recent 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 instead of a flight vehicle so that if something were to break, it wouldn’t have any impact on the flight program.

Masseys Test Site (credit: Jack Beyer for NSF)

Together with ship 26, ship 31 is also at Masseys to carry out cryogenic tests. The other half of ship 31, believed to be Booster 13, recently completed its own cryogenic testing and should begin receiving engines in Mega Bay 1. These two vehicles are expected to fly on Flight 6, which may not be far away.

Ship 31 suffered an anomaly while completing a cryogenic test at Masseys to verify the construction of the tanks. There were several bright flashes of light and smoke on the runway heading 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 turret.

This was most likely an electrical short that caused arcing, damaging Ship 31’s gangway. SpaceX has since rolled this vehicle back to the High Bay and will conduct inspections to see if any additional systems on board have been damaged. If SpaceX suspects this could be a problem with other ships, teams will conduct inspections; however, it could be an isolated incident.

Orbital launch pad B

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

The rollout closures for these moves are from 10 p.m. to 2 a.m. on May 13, 15, 17, 19 and 20. Once these tower sections are at the Sanchez site, SpaceX will begin adding any cryogenic lines and other internal components that may be added before the sections are stacked.

Teams have already rolled out 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 on Roberts Road near Cape Canaveral .

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

According to an FAA document for the Starbase Integration Tower 2 proposal, the tower is to be located square to the piles drilled in the image above.

Environmental Impact Statement for the LC-39A spacecraft

SpaceX has requested a revised Environmental Impact Statement (EIS) regarding spacecraft operations on LC-39A. The FAA and SpaceX had already completed an EIS in 2019. However, the Starship program has changed so much since then, with both launch pad and vehicle changes, that SpaceX has yet to complete an EIS to conduct Starship operations on LC-39A.

An EIS is a study of the environmental impacts a system will have on the environment around it, such as noise waves, pollution, threats to wildlife, and many other factors covered in these reports. Collecting all 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: faa.gov)

The proposed action in this EIS would grant SpaceX an operating license to fly Starship from LC-39A, based on the scope of the proposed action. This proposed action consists of the entirety of Starship Program infrastructure improvements and operations, including those identified in the 2019 EA for Starship.

SpaceX has applied for up to 44 spacecraft launches per year, both day and night. These launches include a Starship or Booster landing at the launch site, a landing on a droneship or a landing in the Atlantic Ocean. With these Starship operations, SpaceX would also continue Falcon 9 and Falcon Heavy operations in addition to the LC-39A.

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

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

In addition to the proposed action, there is an alternative action based on this EIS that could provide the National Aeronautics and Space Administration (NASA) and commercial partners with access to Starship, which is a critical path for NASA’s Artemis program. Given these reasons, the only alternative under the proposal would be a no-action alternative. Under this alternative, SpaceX would not receive a vehicle operating permit and further improvements to the LC-39A would not proceed.

Overall, this means that SpaceX will have to wait to launch from the LC-39A until this EIS is completed and they have been issued a vehicle operator license. This isn’t a bad thing; Once completed, SpaceX will have a much stronger presence and infrastructure on pad LC-39A for spacecraft 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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