SpaceX is moving ahead with expansion plans at Vandenberg Space Force Base that will double its West Coast launch cadence and enable Falcon Heavy rockets to fly from California.
Last week, the Department of the Air Force issued its Draft Environmental Impact Statement (EIS), which considers proposed modifications from SpaceX to Space Launch Complex 6 (SLC-6) at Vandenberg.
At the heart of the request are three key items:
- Modifying the pad to support the launches of both Falcon 9 and Falcon Heavy rockets
- Constructing two new landing pads adjacent to SLC-6
- Increasing SpaceX’s permitted launch cadence from Vandenberg from 50 launches to 100
The transformation of SLC-6 would include quite a bit of overhaul. Its most recent tenant, United Launch Alliance, previously used it for Delta 4 rockets from 2006 through its final launch in September 2022.
SpaceX received a lease from the Air Force beginning in April 2023. In order to support the launches of its Falcon rockets, SpaceX proposed that it modify the existing horizontal integration facility (HIF), similar to that at Launch Complex 39A at Cape Canaveral Space Force Station, along with with adding a transport road to the pad, commodity storage tanks and other ground support equipment.
An alternative would include all over the other provisions, but have SpaceX construct a new 62,000-square-foot HIF to the north of the launch pad.
The ground system overhaul includes 143,000-square-feet of commodity storage for things like liquid oxygen, rocket propellant-1 (RP-1), nitrogen, helium, water and other commodities.
“The Proposed Action is needed to meet current and near-term U.S. Government space launch requirements from the Western Range, specifically for medium and heavy-lift launches to polar, geostationary, and other orbits less reliably available elsewhere, without compromising current launch capabilities,” the summary of the Draft EIS stated. “The Proposed Action is also needed to expand launch capacity by returning heavy-lift launch capability to the Western Range and to fulfill (in part) 10 USC Section 2276(a), ‘Commercial space launch cooperation.’”
That heavy-lift capability would come, in part, from launches of SpaceX’s Falcon Heavy rocket Meanwhile, ULA is currently renovating Space Launch Complex 3 East (SLC-3E) for the use of its Vulcan rocket, which has heavy-lift capability using up to six solid rocket boosters.
The estimated launch cadence between SpaceX’s existing West Coast pad at Space Launch Complex 4 East (SLC-4E) and SLC-6 would be a 70-11 split for Falcon 9 rockets in 2026 with one Falcon Heavy at SLC-6 for a total of 82 launches. That would increase to a 70-25 Falcon 9 split in 2027 and 2028 with an estimated five Falcon Heavy launches in each of those years.
The proposed ramped-up launch cadence encompasses both SLC-4E and SLC-6. It would also allow for up to 12 landings annually at Landing Zone 4 for years 2025-2028 and up to 12 landings annually at SLC-6 for years 2026-2028.
The two new landing zones at SLC-6 would be 280 feet in diameter with each concrete pad surrounded by a 60-foot gravel apron. The total footprint of the landing site would around 16 acres. There would also be a 50-foot-wide firebreak south of the landing zones that connects to the existing firebreak at SLC-8, which is used by Northrop Grumman to launch its Minotaur 4 rockets.
As for launch preparations, the proposal would allow for no more than 50 static fire tests between SLC-4E and SLC-6 annually. It would allow for launches from both pads on the same day as well.
A 45-day public review and comment period on the Draft EIS runs from May 23 through July 7. The Final EIS is anticipated to be published in the Fall of 2025 with a Record of Decision potentially issued no earlier than 30 days after the Final EIS is issued.
Click here for information about submitting a comment on the Draft EIS and reviewing the associated documents.
Vetting the impacts
In crafting the Draft EIS, the Air Force called upon the analysis of a variety of sources, from potential impacts to air and water quality to potential disturbances of sensitive cultural materials.
In a letter to the Santa Ynez Band of Chumash Indians (SYBCI), Josh Smallwood, the Vandenberg base archeologist determined that the proposed construction and increase in launch cadence “will have no potential to affect a historic property” as outlined in the National Historic Preservation Act.
Back on Jan. 21, 2025, the SYBCI stated that it had concerns with the proposed action by SpaceX and requested a site visit. According to the Draft EIS, multiple dates in February were offered, but said despite a follow-up request for a comment and a date for the visit from the Tribe, as of April 30, the Tribe “had not scheduled a site visit or identified any perceived potential effects.”
The amount of water used at SLC-6 would be about 1.5 million gallons for each Falcon Heavy launch. It would require 200,000 gallons per Falcon 9 launch for the deluge system compared to about 70,000 gallons per launch at SLC-4E.
“More water is required at SLC-6 because the existing flame bucket is substantially larger than at SLC-4, thus requiring more water to achieve the same operational objectives in reducing vibration below the vehicle,” the Draft EIS stated.
In its analysis, the Department of the Air Force determined that the level of water use at SLC-6 “would not have detectable impacts on the San Antonio Creek basin” and therefore “not have a significant impact on surface water or groundwater resources.” It said that SpaceX would also use so-called best management practices that would prevent significant impacts to wetlands.
As for the noise generated by both the launches themselves as well as the sonic booms from land landings of the first stage boosters, the Federal Aviation Administration determined that the maximum estimated C-weighted Day-Night Average Sound Level (CDNL) would be 58.0 dBC, which is below the FAA’s 60 dBC significant impact threshold.
Regarding wildlife impacts, the U.S. Fish and Wildlife Service determined that with continued species monitoring, “modifications to SLC-6 and increased Falcon launches would not be likely to jeopardize the continued existence of a federally listed threatened or endangered species or result in the destruction or adverse modification of federally designated Critical Habitat resources.”
“In addition, these measures would decrease the potential for long-term habitat and species loss, as well as adverse effects on reproductive success, mortality rate, or ability to sustain minimum population levels, such that there would be no significant impact,” the Draft EIS stated.
The document stated that the proposed action’s impacts “may affect, but not likely to adversely affect” Endangered Species Act-listed fish species, sea turtle species and the humpback whale critical habitat.
The need for ramping up
Part of SpaceX’s desired to add a new launch site to its three existing pads across California and Florida is to add launch capacity for both commercial and government customers.
That includes 23 missions assigned from the National Security Space Launch (NSSL) Phase 2, of which 19 are still remaining. SpaceX launched the USSF-67 (Jan. 15, 2023), USSF-124 (Feb. 14, 2024), USSF-62 (Apr. 11, 2024), NROL-69 (Mar. 24, 2025) previously.
The company was also tapped as the Requirement 1 provider for the NSSL Phase 3 Lane 2 contact, which will award about 28 missions to the company from FY25-FY29.
A necessity for this newest contract is bringing online vertical integration from the Eastern Range in Florida. Walt Lauderdale, the Chief of Falcon Systems and Operations within the Launch Execution Division of the Space Systems Command’s Assured Access to Space told Spaceflight Now back in December 2023 that SpaceX was looking to bring that capability online at Launch Complex 39A at the Kennedy Space Center.
“SpaceX, knowing that this is a requirement, had done some preemptive work or some early work several years ago, extended the flame trench at 39 in order to support that capability,” Lauderdale said at the time. “So, they basically plumbed in the basics where it was smart to do so they were ready to make that capability available for any mission we assign them.”
As of May 2025, vertical integration is not available for customers at LC-39A, like that at ULA’s Space Launch Complex 41 (SLC-41). In a written response to questions from Spaceflight Now, Col. Doug Pentecost, the Deputy Program Executive Officer within AATS, clarified the vertical integration requirements from the Phase 2 and Phase 3 contracts.
“The NSSL Phase 2 contract only requires vertical integration on the Eastern Range; none of the missions assigned to SpaceX under the NSSL Phase 2 contract required vertical integration capability and there are no missions under the Phase 3 contract projected to require vertical integration capability on the Western Range (Vandenberg SFB),” Pentecost said. “Vertical integration capability on the Eastern Range (Cape Canaveral SFS or Kennedy Space Center) is a unique mission item on the Phase 3 contract.
“If a launch provider does not have a vertical integration capability certified by 1 October of each order year, then that launch provider would not be eligible to be assigned a mission requiring vertical integration.”
The proposed upgrades at SLC-6 would fulfill one of the requirements of the NSSL Phase 2 contract, which is to to bring Falcon Heavy launch capabilities online at VSFB. As of now, Pentecost said SpaceX has not been assigned any missions that require a Falcon Heavy launch from the West Coast.
“The first projected opportunity would come in NSSL Phase 3 Order Year 4 (FY28) for a launch in FY30,” he said.
