Ellsworth Air Force Base (AFB) (IATA: RCA, ICAO: KRCA, FAA LID: RCA) is a United States Air Force (USAF) base located about 10 miles (16 km) northeast of Rapid City, South Dakota, just north of the town of Box Elder.

[citation needed] For decades, Ellsworth's main entrance included a symbolic B-52 Stratofortress, a gift from the citizens of Rapid City.

It was later renamed for Brigadier General Richard E. Ellsworth (1911–1953), a 28th Strategic Reconnaissance Wing commander killed when his RB-36 Peacemaker aircraft crashed near Burgoyens Cove, Newfoundland, during a training flight.

The field's instructors taught thousands of pilots, navigators, radio operators and gunners from nine heavy bombardment groups and numerous smaller units.

On 15 July 1945, the 225th AAFBU was inactivated and Rapid City AAB was placed on standby status as the United States Army Air Forces (USAAF) began to demobilize.

The base briefly trained weather reconnaissance and combat squadrons using P-61 Black Widow, P-38 Lightning, P-51 Mustang, and B-25 Mitchell aircraft.

In March 1953, an RB-36 crashed in Newfoundland while returning from a routine exercise in Europe, killing all 23 aboard, including brigadier general Richard E. Ellsworth, commander of the 28th Strategic Reconnaissance Wing.

The base was subsequently renamed Ellsworth AFB, and unlike the previous local controversy in 1948, there was no community objection to the name change.

As a GCI station, the squadron's role was to guide interceptor aircraft toward unidentified intruders picked up on the unit's radar scopes.

3 were on ground alert around-the-clock providing ALCS coverage for five of the six Minuteman intercontinental ballistic missile (ICBM) Wings.

2's dedicated role was to take off and orbit near the Minuteman ICBM Wing at Malmstrom AFB, Montana, providing ALCS assistance if needed.

Contractors completed new unaccompanied enlisted dormitories in March, a new security police squadron headquarters in October, and gave Ellsworth's 13,497-foot (4,114 m) runway a much-needed facelift.

In October 1960, Ellsworth entered the "Space Age," with the activation of the 850th Strategic Missile Squadron, initially assigned to the 28 BMW.

After the Berlin Wall fell in November 1989, presaging the demise of the Soviet Union, the USAF reshuffled its organizations and resources to meet a shifting, diminishing, threat.

On 31 July 1990, SAC replaced the 12th Air Division with the Strategic Warfare Center (SWC), which provided operational command and administrative control over Ellsworth's subordinate units.

It was also during this period that, in acknowledgment of the elimination of the Warsaw Pact, that the President, via the Secretary of Defense, ordered all strategic nuclear alert operations to stand-down.

Under conditions of the Strategic Arms Reduction Treaty, all of the 44th Missile Wing's Minuteman silos and launch control centers were slated for demolition with the exception of Sites Delta-01 and Delta-09.

[11] In March 1994, Ellsworth welcomed the 34th Bomb Squadron, a Geographically Separate Unit (GSU) that was awaiting airfield upgrades before it could return to its parent organization, the 366th Wing (366 WG), at Mountain Home AFB, Idaho.

Also during 1994, the USAF selected Ellsworth as the exclusive location from which to conduct a Congressionally mandated operational readiness assessment of the B-1B, known locally as "Dakota Challenge."

After six months of hard work, under both peacetime and simulated wartime conditions, the 28 BW and Ellsworth, relying on extensive personnel, technical and logistical support from sister B-1 units at McConnell, Grand Forks and Dyess Air Force Bases, passed the test "with flying colors"; and proved the B-1 to be a reliable and capable weapons system; the mainstay of America's heavy bomber fleet for years to come.

The expeditionary force construct enables the USAF to respond quickly to any worldwide crisis while making life more predictable for military members.

By the end of the conflict in June 1999, B-1Bs from Ellsworth had flown 100 combat missions and dropped over 1,260 tons of Mk 82 general-purpose bombs.

On 19 September 2001 the "Thunderbirds" of the 34th Bomb Squadron arrived from Mountain Home AFB, Idaho to rejoin the Ellsworth team.

During the 2004 Senate race in South Dakota, Republican challenger John Thune made Ellsworth a campaign issue, stating in a 16 April 2004 appearance at the base that if he were elected over incumbent Democrat and Senate Minority Leader Tom Daschle: "It puts Ellsworth in a lot stronger position than having someone who's going to be in the minority and someone who doesn't have a relationship with the President of the U.S."[citation needed] In a debate between the two men broadcast on KSFY-TV and KOTA-TV television on 17 October 2004, Thune said: "I think we have got to have somebody that has a relationship with the President of the United States, can work constructively across party lines in the Congress to get this done if we're going save Ellsworth" and was later quoted in the "Rapid City Journal" newspaper on 27 October 2004 claiming that: "an all-Democratic congressional delegation would have little political influence if President Bush is elected to a second term.

"[citation needed] On 24 May 2004 campaigning in South Dakota for Thune, Senate Majority Leader Bill Frist said of Daschle: "Who is the president going to listen to more?

[citation needed] Thune stated in protest he would vote against confirmation of the president's nominee for United Nations Ambassador, John Bolton.

The missile launch sites (again, with the exception of D-09) are all in private ownership, most being used for agricultural use, the remainder abandoned and returning to a natural state.

Remedies have included groundwater pump-and-treat systems, bio-dechlorination, soil excavation, landfill covers, and institutional controls (fences/signs).

[19] In February 2014 the air force found 12 places that needed more testing due to possible PFC contamination from A-FFF, a fire-fighting foam.

in addition a site at the south end of the base, where former firefighters trained using A-FFF will be investigated with field work completed in August 2016.