Vandenberg Space Launch Complex 6

Space Launch Complex 6

Delta IV Heavy lifts off from SLC-6 in August 2013
Launch site	Vandenberg Space Force Base
Location	34°34′53″N 120°37′36″W / 34.5813°N 120.6266°W / 34.5813; -120.6266
Time zone	UTC−08:00 (PST)
• Summer (DST)	UTC−07:00 (PDT)
Short name	SLC-6
Operator	United States Space Force
Launch pad(s)	1
Orbital inclination range	55–145°[1]
Launch history Status Inactive, pending modifications for SpaceX Launches 19 First launch 15 August 1995 Athena I (GemStar-1) Last launch 24 September 2022 Delta IV Heavy (NROL-91) Associated rockets Future: Falcon 9, Falcon Heavy Retired: Athena I, Athena II, Delta IV, Delta IV Heavy Plans cancelled: OmegA,[2] Space Shuttle, Titan IIIC, Titan IIIM, Titan IV

Vandenberg Space Launch Complex 6 (SLC-6, pronounced "Slick Six") is a launch pad and associated support infrastructure at Vandenberg Space Force Base in California. Construction at the site began in 1966, but the first launch didn't occur until 1995 due to program cancellations and subsequent repurposing efforts.

The site was originally envisioned to support Titan IIIM rockets and the Manned Orbiting Laboratory, however, these projects were terminated before SLC-6's completion. Between 1979 and 1986 the facilities received extensive modifications to accommodate the Space Shuttle. However, budgetary constraints, safety considerations, and political factors ultimately led to the cancellation of Shuttle operations from the West Coast.

SLC-6 facilitated four launches of Athena rockets between 1995 and 1999 with minimal modifications. Subsequently, it underwent modifications to support the Delta IV and Delta IV Heavy, which conducted ten successful missions between 2006 and 2022. In 2023, SpaceX secured a lease agreement for SLC-6, with plans to modify the facility for Falcon 9 and Falcon Heavy launches commencing in 2025.

Vandenberg's southward launch trajectory is advantageous for deploying satellites into high-inclination polar and Sun-synchronous orbits, needed for weather forecasting, Earth observation, and reconnaissance missions as they enable comprehensive and regular global coverage. Launching into such orbits from the East Coast of the United States presents significant challenges due to geographical constraints.^[3]