Space Launch Complex 2 (SLC-2) is an active

rocket launch A rocket (from , and so named for its shape) is a vehicle that uses jet propulsion to accelerate without using any surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely fr ...

site at

Vandenberg Space Force Base Vandenberg Space Force Base , previously Vandenberg Air Force Base, is a United States Space Force Base in Santa Barbara County, California. Established in 1941, Vandenberg Space Force Base is a space launch base, launching spacecraft from the ...

, in

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

USA The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 states and a federal capital district, Washington, D.C. The 48 contiguous ...

. It consists of two

launch pad A launch pad is an above-ground facility from which a rocket-powered missile or space vehicle is vertically launched. The term ''launch pad'' can be used to describe just the central launch platform (mobile launcher platform), or the entire c ...

s: Space Launch Complex 2 East (SLC-2E, originally LC 75-1-1), used by the

PGM-17 Thor The PGM-17A Thor was the first operative ballistic missile of the United States Air Force (USAF). It was named after the Thor, Norse god of thunder. It was deployed in the United Kingdom between 1959 and September 1963 as an intermediate-range b ...

missile and several of its derivatives from 1958 to 1972; and Space Launch Complex 2 West (SLC-2W, originally LC 75-1-2), which has been in use since 1959 to launch the Thor-Delta family and

Delta II Delta II was an expendable launch system, originally designed and built by McDonnell Douglas, and sometimes known as the Thorad Delta 1. Delta II was part of the Delta rocket family, derived directly from the Delta 3000, and entered service in ...

, and is currently used by the

Firefly Alpha Firefly Alpha (Firefly α) is a two-stage orbital expendable small lift launch vehicle developed by the American company Firefly Aerospace to compete in the commercial small satellite launch market. Alpha is intended to provide launch o ...

. Space Launch Complex 2 was originally part of Launch Complex 75 (LC 75) and was known by designation LC 75-1 or just 75-1 (and the launch pads were designated LC 75-1-1 and LC 75–1–2). The first launch out of the newly designated Space Launch Complex 2 was that of a

Delta E The Delta E, or Thor-Delta E was an American expendable launch system used for twenty-three orbital launches between 1965 and 1971. It was a member of the Delta family of rockets. The first stage was a Thor missile in the DSV-2C configuration, ...

with ESSA-3 on 2 October 1966 from SLC-2E. SLC-2E and SLC-2W are located approximately apart.

SLC-2W

Thor and Thor-Agena (1959–1968)

Space Launch Complex 2 West (originally Launch Complex 75-1-2) was built in the late 1950s to launch the

for use in suborbital tests, being jointly operated by the

United States Air Force The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...

and the

Royal Air Force The Royal Air Force (RAF) is the Air force, air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the World War I, First World War on 1 April 1918, on the merger of t ...

in accordance to the

IRBM An intermediate-range ballistic missile (IRBM) is a ballistic missile with a range between (), categorized between a medium-range ballistic missile (MRBM) and an intercontinental ballistic missile (ICBM). Classifying ballistic missiles by ran ...

's stationing in

Britain Britain most often refers to: * Great Britain, a large island comprising the countries of England, Scotland and Wales * The United Kingdom of Great Britain and Northern Ireland, a sovereign state in Europe comprising Great Britain and the north-eas ...

as part of

Project Emily Project Emily was the deployment of American-built Thor intermediate-range ballistic missiles (IRBMs) in the United Kingdom between 1959 and 1963. Royal Air Force (RAF) Bomber Command operated 60 Thor missiles, dispersed to 20 RAF air stations ...

. It saw its first launch on September 17, 1959, with launches being held over the next four months and all but one being successful. Following the last flight on January 21, 1960, the pad underwent the conversion into an orbital launch complex, as the Thor got decommissioned from missile use and was replaced by ICBMs such as the

LGM-25C Titan II The Titan II was an intercontinental ballistic missile (ICBM) developed by the Glenn L. Martin Company from the earlier HGM-25A Titan I, Titan I missile. Titan II was originally designed and used as an ICBM, but was later adapted as a Med ...

. As per its new use, LC 75-1-2 was subsequently designed to launch the

Thor-Agena Thor-Agena was a series of orbital launch vehicles. The launch vehicles used the Douglas Aircraft Company, Douglas-built Thor (rocket family), Thor first Multistage rocket, stage and the Lockheed Corporation, Lockheed-built RM-81 Agena, Agena ...

and the

Thor-Ablestar The Thor-Ablestar, or Thor-Able-Star, also known as Thor-Epsilon was an early American expendable launch system consisting of a PGM-17 Thor missile, with an Ablestar upper stage. It was a member of the Thor family of rockets, and was derived fro ...

to compliment the nearby SLC-1E and 1W in its capabilities of putting satellites into

polar orbit A polar orbit is one in which a satellite passes above or nearly above both poles of the body being orbited (usually a planet such as the Earth, but possibly another body such as the Moon or Sun) on each revolution. It has an inclination of abo ...

. Over the next seven years, it was put into use 21 times for nineteen Agena and two Ablestar launches, with the overwhelming majority of payloads being reconnaissance satellites such as the KH-4 for military customers like the

National Reconnaissance Office The National Reconnaissance Office (NRO) is a member of the United States Intelligence Community and an agency of the United States Department of Defense which designs, builds, launches, and operates the reconnaissance satellites of the U.S. f ...

Early Delta (1969–1989)

With the

Department of Defense The United States Department of Defense (DoD, USDOD, or DOD) is an executive department of the U.S. federal government charged with coordinating and supervising the six U.S. armed services: the Army, Navy, Marines, Air Force, Space Force, ...

seeing its payloads grow in size throughout the late 1960s (as seen by satellites such as the

KH-9 KH-9 (Byeman Control System, BYEMAN codename HEXAGON), commonly known as Big Bird or KeyHole-9, p.32 Big Bird was a series of photographic reconnaissance satellites launched by the United States between 1971 and 1986. Of twenty launch attempt ...

and

KH-11 The KH-11 KENNEN (later renamed CRYSTAL,p.199-200 then Evolved Enhanced CRYSTAL System, and codenamed 1010 and Key Hole) is a type of reconnaissance satellite first launched by the American National Reconnaissance Office (NRO) in December 19 ...

getting developed), both the Thor-Agena and Thor-Ablestar were retired and the pad received another modification under the SLC-2W name, this time to act as the west coast site of the

Thor-Delta The Thor-Delta, also known as Delta DM-19 or just Delta was an early American expendable launch system used for 12 orbital launches in the early 1960s. A derivative of the Thor-Able, it was a member of the Thor family of rockets, and the first ...

and its derivatives to complement LC-17 at

Cape Canaveral Cape Canaveral () is a cape (geography), cape in Brevard County, Florida, in the United States, near the center of the state's Atlantic Ocean, Atlantic coast. Officially Cape Kennedy from 1963 to 1973, it lies east of Merritt Island, separated ...

. Throughout this period of the pad's history, 26 Delta launches were performed at the site, carrying various payloads for the DoD,

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

NOAA The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with forecasting weather, monitoring oceanic and atmospheric conditions, charting the seas, conducting deep-sea exploratio ...

, and a handful of international agencies such as ESA. During the late 70s, a mobile service tower was constructed at SLC-2W to help support the various Delta evolutions by creating an enclosed environment. As the 1980s arrived and went along, the site gradually saw slowing use in the wake of the Delta family's expected replacement with the

Space Shuttle The Space Shuttle is a retired, partially reusable launch system, reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. ...

, which was slated to have its own west coast launch site at SLC-6. Despite all California Shuttle plans getting axed following the ''Challeneger'' disaster in 1986, SLC-2W only saw one last liftoff in this configuration on November 18, 1989, with a

Delta 5000 The Delta 5000 series was an American expendable launch system which was used to conduct an orbital launch in 1989. It was a member of the Delta family of rockets. Although several variants were put forward, only the Delta 5920 was launched. The ...

being used to launch the

Cosmic Background Explorer The Cosmic Background Explorer (COBE ), also referred to as Explorer 66, was a NASA satellite dedicated to cosmology, which operated from 1989 to 1993. Its goals were to investigate the cosmic microwave background radiation (CMB or CMBR) of th ...

(COBE) for NASA.

Delta II (1995–2018)

After getting mothballed for a half decade,

McDonnell Douglas McDonnell Douglas Corporation was a major American Aerospace manufacturer, aerospace manufacturing corporation and defense contractor, formed by the merger of McDonnell Aircraft and the Douglas Aircraft Company in 1967. Between then and its own ...

revived SLC-2W in 1994 for use as the polar orbit site of their successor to the Thor-Delta rockets, the

. The first launch in this new era was on November 4, 1995, carrying

Radarsat-1 RADARSAT-1 was Canada's first commercial Earth observation satellite. It utilized synthetic aperture radar (SAR) to obtain images of the Earth's surface to manage natural resources and monitor global climate change. As of March 2013, the sate ...

for the

Canadian Space Agency The Canadian Space Agency (CSA; ) is the national space agency of Canada, established in 1990 by the ''Canadian Space Agency Act''. The President of the Canadian Space Agency, president is Lisa Campbell (civil servant), Lisa Campbell, who took ...

and a

Deep Space Network The NASA Deep Space Network (DSN) is a worldwide Telecommunications network, network of spacecraft communication ground segment facilities, located in the United States (California), Spain (Madrid), and Australia (Canberra), that supports NASA' ...

test satellite for NASA. Over the next 23 years, the pad saw 45 Delta II launches and delivered various payloads to polar orbit for numerous governmental agencies and commercial customers. Among the more notable payloads of this era are

Aqua Aqua is the Latin word for water. As such, it is often used in many words which relate to water, such as aquatic life. In English, it may also refer to: Arts * Aqua (color), a greenish-blue color Business * Aqua (Chicago), an 82-story resid ...

, Aura,

Gravity Probe B Gravity Probe B (GP-B) was a satellite-based experiment whose objective was to test two previously-unverified predictions of general relativity: the geodetic effect and frame-dragging. This was to be accomplished by measuring, very precisely, t ...

, and the

Wide-field Infrared Survey Explorer Wide-field Infrared Survey Explorer (WISE, List of observatory codes, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy Space observatory, space telescope in the Explorers Program launched in December 2009.. . WISE L ...

(WISE). Additionally, SLC-2W followed the Delta II in changing hands regarding operation; it went from McDonnell Douglas to

Boeing The Boeing Company, or simply Boeing (), is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, and missiles worldwide. The company also provides leasing and product support s ...

following their merger in 1997, and was subsequently passed to

United Launch Alliance United Launch Alliance, LLC (ULA) is an American launch service provider formed in December 2006 as a joint venture between Lockheed Martin Space and Boeing Defense, Space & Security. The company designs, assembles, sells and launches rockets ...

following the 2006 formation of the Boeing-

Lockheed Martin The Lockheed Martin Corporation is an American Arms industry, defense and aerospace manufacturer with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta on March 15, 1995. It is headquartered in North ...

joint venture. The site eventually wound down in use again throughout the 2010s following the Delta II's retirement from Cape Canaveral in 2011, and saw its last flight of a Thor-derived vehicle (and last launch of one in general) with the launch of

ICESat-2 ICESat-2 (Ice, Cloud, and land Elevation Satellite 2), part of NASA's Earth Observing System, is a satellite mission for measuring ice sheet elevation and sea ice thickness, as well as land topography, vegetation characteristics, and clouds. ICES ...

on September 12, 2018.

Firefly Aerospace (2019–present)

Following the Delta II's retirement, SLC-2W was leased out to

Firefly Aerospace Firefly Aerospace, Inc. is an American private aerospace firm based in Cedar Park, Texas, that develops small- and medium-lift launch vehicles for commercial launches to orbit. The current company was formed when the assets of the former co ...

and repurposed to launch the

. During the demolition process, a fire broke out inside the Delta II mobile service tower on October 15, 2020, though no injuries were reported. The maiden flight of Alpha took place on September 3, 2021, and resulted in a flight failure following an engine failure causing a

range safety In rocketry, range safety or flight safety is ensured by monitoring the flight paths of missiles and launch vehicles, and enforcing strict guidelines for rocket construction and ground-based operations. Various measures are implemented to protect ...

activation at

transonic Transonic (or transsonic) flow is air flowing around an object at a speed that generates regions of both subsonic and Supersonic speed, supersonic airflow around that object. The exact range of speeds depends on the object's critical Mach numb ...

speeds. Firefly would not attempt a second flight until October 1, 2022, which was successful in reaching orbit. That same year, Firefly and

Northrop Grumman Northrop Grumman Corporation is an American multinational Aerospace manufacturer, aerospace and Arms industry, defense company. With 97,000 employees and an annual revenue in excess of $40 billion, it is one of the world's largest Arms industry ...

announced their collaborative Medium Launch Vehicle (now known as

Eclipse An eclipse is an astronomical event which occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three ...

) was in development, and that it will also be using SLC-2W as a polar launch site.

Gallery

File:Landsat 1 launch.jpg, SLC-2W in 1972, preparing to launch Landsat-1 File:COBELaunch.jpg, A

carrying COBE launching from SLC-2W in 1989 File:Mobile Service Tower rolls over the Delta II on SLC-2W.jpg, SLC-2W during its

years, carrying

in 2004 File:Delta II 7920 ignition with Gravity Probe B.jpg, Another view of SLC-2W launching Gravity Probe B File:Firefly Alpha 1st Flight.jpg, The maiden flight of

, launching from SLC-2W in 2021

SLC-2E

Space Launch Complex 2 East, originally built as Launch Complex 75-1-1, was similar to its western counterpart through its use by the USAF and RAF for Thor missile tests. During this initial period, the pad hosted its first launch on December 18, 1958, and saw three additional flights throughout the next year. Following the retirement of the Thor, LC 75-1-1 got modified in 1960 to launch the Thor-Agena and Thor-Ablestar to increase launch cadence for the military at the base, and each rocket saw 23 and 6 launches from there respectively. Among the most notable launches of that era includes

Alouette 1 ''Alouette 1'' is a deactivated Canadian satellite that studied the ionosphere. Launched in 1962, it was Canada's first satellite, and the first satellite constructed by a country other than the Soviet Union or the United States. Canada was ...

, the first

Canadian Canadians () are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of their being ''C ...

satellite. In 1966, the pad got renamed to SLC-2E. As the Thor-Agena and Thor-Ablestar got phased out from use in the late 1960s, SLC-2E likewise saw a gradual conversion for use by the Thor-Delta and

Thorad-Agena Thorad-Agena was an American expendable launch system, derived from the Thor and Delta rockets. The first stage of the rocket was a stretched Thor variant named "Long Tank Thrust Augmented Thor". The Long Tank Thor first stage was later adopted ...

. During this era, the pad witnessed a total of 19 launches of various government satellites, with fourteen being from the Delta line and five being from the Thorad family. The last launch from SLC-2E came on March 12, 1972, seeing a

Delta N Delta commonly refers to: * Delta (letter) (Δ or δ), the fourth letter of the Greek alphabet * D (NATO phonetic alphabet: "Delta"), the fourth letter in the Latin alphabet * River delta, at a river mouth * Delta Air Lines, a major US carrier ...

propel

TD-1A TD-1A, or Thor-Delta 1A (or just TD-1), was a European astrophysical research satellite which was launched in 1972. Operated by the European Space Research Organisation, TD-1A made astronomical surveys primarily in the ultraviolet, but also using ...

into orbit for

ESRO The European Space Research Organisation (ESRO) was an international organisation founded by 10 European nations with the intention of jointly pursuing scientific research in space. It was founded in 1964. As an organisation ESRO was based on a ...

. Much like SLC-1E and 1W, SLC-2E got mothballed to concentrate launches in the area at SLC-2W. In the years following its deactivation, most structures at SLC-2E have been demolished.

Launch statistics

SLC-2W

Statistics

List of launches

= Thor and derivatives

= All launches operated by the

= Early Delta

= All launches operated by

= Delta II

= All launches until July 1997 operated by

. All launches from August 1997 to April 2006 operated by

. All launches since December 2006 operated by

= Alpha

= All launches operated by

SLC-2E

Statistics

List of launches

All Thor and derivative launches operated by the

. All Delta and Thorad launches operated by

References

External links

Encyclopedia Astronautica - Vandenberg SLC-2
{{DEFAULTSORT:Vandenberg Afb Space Launch Complex 2 Vandenberg Space Force Base Launch complexes of the United States Space Force Buildings and structures in Santa Barbara County, California 1958 establishments in California Firefly Aerospace facilities

SLC-2W

Thor and Thor-Agena (1959–1968)

Early Delta (1969–1989)

Delta II (1995–2018)

Firefly Aerospace (2019–present)

Gallery

SLC-2E

Launch statistics

SLC-2W

Statistics

List of launches

= Thor and derivatives

= Early Delta

= Delta II

= Alpha

SLC-2E

Statistics

List of launches

See also

References

External links