Construction crews began on Aug. 2, 2011, tearing down the mobile service tower at Vandenberg Air Force Base's Space Launch Complex-4 East (4E) in preparation for converting the pad to support Space Exploration Technologies (SpaceX) Falcon Heavy
Space Launch Complex 4 (SLC-4), was previously used for launching Atlas and Titan rockets between 1963 and 2005. It consisted of two separate launch pads, SLC-4W and SLC-4E, which were formerly designated PALC2-3 and PALC2-4 respectively.
Both pads were originally built for use by Atlas-Agena rockets, but were later rebuilt to handle Titan rockets. The designation SLC-4 was applied at the time of the conversion to launch Titans.
The first launch from PALC2-4 (SLC-4E) occurred on Aug. 14 1964, when a KH-7 satellite was launched by an Atlas-Agena D. After 27 Atlas-Agena launches, the last of which was on June 4, 1967, the complex was deactivated.
In 1971, PALC2-4 was reactivated as a Titan IIID launch site, designated SLC-4E, with the first launch occurring on June 15. Twenty two (22) Titan IIIDs were launched, until Nov. 17, 1982, when the type was replaced by the Titan 34D.
Seven 34Ds were launched between June 20, 1983, and Nov. 6, 1988. On April 18, 1986, a 34D exploded less than nine seconds after launch, showering debris over the launch pad.
The last type to use the complex was the Titan IV, starting on March 8, 1991, with the launch of Lacrosse 2.
On Oct. 19, 2005, the last flight of a Titan rocket occurred, when a Titan IVB was launched from SLC-4E, with an Improved Crystal satellite.
Following that launch, the complex was deactivated, having been used for 68 launches.
SpaceX will reactivate SLC–4E for Falcon Heavy launches following a 24 month refurbishment, now underway, with liftoff to follow soon thereafter.