Instruct: Given a question, retrieve relevant documents that answer the question.
Query: When did construction on Caribou Air Force Station begin?
In 1951, the Department of Defense (DOD) allocated funds for the construction of an ordnance storage site at Loring AFB. The designs called for a self-sufficient "maximum security storage area for the most advanced weapons of mankind". The mission of the facility would be the protection and maintenance of the weapons used by SAC. The facility was in the northeast corner of the base, and construction began on 4 August 1951. In addition to 28 storage igloos and other weapons storage structures, the facility included weapons maintenance buildings, barracks, recreational facilities, a warehouse, and offices.[19]
In June 1962, the Atomic Energy Commission released its custody and ownership of the weapons to the Air Force. The personnel and property of the later named Caribou Air Force Station were absorbed into the adjacent Loring Air Force Base.[19]
Nearby to the northeast, Loring Air Force Base opened in the early 1950s near Limestone, with bomber and tanker aircraft of the Strategic Air Command. It provided a major economic boost to the area, with construction starting in 1947 on "Limestone Army Air Field." Caribou was incorporated as a city in 1967 on February 23, but the area's boom period leveled off in the 1970s as a result of difficulties in its traditional potato industry. That, along with closure of the base in 1994, contributed to a decline in population in the 1980s and 1990s.
Caribou Air Force Station, also known as North River Depot and East Loring, is a defunct Air Force Station that operated from 1951 until some time when it was absorbed into Loring Air Force Base in 1962. It was located in Limestone, Maine, adjacent to Loring. Between 1951 and 1962 Caribou was an Operational Storage Site for Air Materiel Command (AMC-OSS), one of five in the United States, and the weapons storage and maintenance facility for Loring alert aircraft.
North Bend Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary’s approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.
Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of additional stations, and it received the Defense Secretary’s approval on July 21, the Air Force directed the Army Corps of Engineers to proceed with construction of Palermo Air Force Station. The 770th Aircraft Control & Warning Squadron was activated to control the site.
Blaine Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary's approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.
Rockville Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary's approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.
Mount Laguna Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary’s approval on July 21, the Air Force directed the United States Army Corps of Engineers to proceed with construction.
The base's origins began in 1947 with an order for construction of an airfield by the New England Division of the United States Army Corps of Engineers. The chosen site, in northeastern Maine within both Limestone Township and Caswell Plantation, was the closest point in the continental U.S. to Europe, providing high strategic value during the Cold War. The base was originally named Limestone Army Air Field, and was renamed Limestone Air Force Base following the establishment of the Air Force in 1947. It was named in 1954 for Major Charles J. Loring, Jr., USAF, a Medal of Honor recipient during the Korean War. From 1951 to 1962, it was co-located next to Caribou Air Force Station.
Some U.S. Caribou were captured by North Vietnamese forces and remained in service with that country through to the late 1970s. Following the war in Vietnam, all USAF Caribou were transferred to Air Force Reserve and Air National Guard airlift units pending their replacement by the C-130 Hercules in the 1980s.
Caribou Air Force Station was the first of five, United States Air Force, Air Material Command (AMC) installations that were constructed during the period of 1951 – 1953. Each of the five installations was built specifically to provide operational storage of the nuclear stockpile, and to provide a specified number of weapons to their adjacent Strategic Air Command (SAC) bases. The first four installations were built and occupied by 1953. The fifth installation, although completed in 1953, would not be utilized until 1955. The first installation, code named “Site Easy” was originally known as the “North River Depot”. It was constructed between 1951-1952, and operations began in 1952. Funds were provided in 1951 to the Armed Forces Special Weapons Project (AFSWP), for the planning and construction of an ordnance storage site in the vicinity of a new Strategic Air Command Base. The AFSWP was directed to utilize the services of the Corps of Engineers, Department of Army, for planning and construction, and was made responsible for monitoring such work, and for operational security measures during these phases. The original directive to the AFSWP stipulated that upon completion of construction the installation would be turned over to Headquarters, Air Material Command for operational responsibilities.
Boron Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary’s approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.
The Howze Board was also shaped by the growing conflict in South Vietnam and tensions between the Army and Air Force regarding the Army's aviation program in general. Under earlier agreements, the Army could only operate aircraft under certain weight and size restrictions. There were also limits placed on arming such aircraft. The Air Force focused its objections on Army fixed wing aircraft (the OV-1 Mohawk and Caribou), and the Caribou was transferred to the Air Force in 1966. Before the Howze Board "the Caribou and the Mohawk were the two major symbols of Army-Air Force disagreement and more time was devoted to these systems than to the entire mobility concept itself."
Port Austin Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary’s approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.
Campion Air Force Station (AFS) was a continental defense radar station constructed to provide the United States Air Force early warning of an attack by the Soviet Union on Alaska. It was one of the ten original aircraft control and warning sites constructed during the early 1950s to establish a permanent air defense system in Alaska. The station was named in honor of Lieutenant Alan J. Campion, 449th Fighter Interceptor Squadron, Ladd AFB, who was killed on 26 November 1950 when the Lockheed F-94 Starfire interceptor he was flying crashed while attempting to land at nearby Galena AFB, Alaska.
The history of Youngstown ARS dates to the early 1950s when it was originally opened as Youngstown Air Force Base. Beginning in 1951, the Air Defense Command (ADC) began negotiations with the local community to construct an Air Force Base to defend the north-central United States. Negotiations were finalized and the new base was dedicated on 11 August 1952. 
Omaha Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary’s approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.
The Victorville Army Airfield was constructed beginning in 1941. It was renamed as the George Air Force Base when the U.S. Air Force was established in October 1947. After decades of service to the Air Force, in 1992 George Air Force Base was closed.
Bellefontaine Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary’s approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.
The war brought increased funding to Limestone in 1951. Eight additional hangars were constructed at the southwestern end of the runway, as well as a 2,100-foot (640m) addition to the northern end of the runway. The Department of Defense allocated funds for the North River Depot, a weapons storage facility to the northwest of the base. It later became Caribou Air Force Station and was absorbed into the facility in the 1960s. The end of the year brought the completion of a communications facility, a hospital, three barracks, a school, an officers club, a bakery, and a briefing and training building. The base was one of the first constructed after World War II and also one of the first to retain as much surrounding vegetation as possible in case there was a need to camouflage the airfield and surrounding facilities. It avoided the traditional grid system for roads.[1]
The Nuclear Weapons Storage Area at Loring once operated as a separate, top secret facility. Originally called the North River Depot, the remote area to the northeast of Loring’s property was the first U.S. Operational site allegedly constructed for the storage, assembly, and testing of atomic weapons.
In June 1962, the United States Atomic Energy Commission released its custody and ownership of the weapons to the Air Force, and the personnel and property were absorbed into the adjacent Loring Air Force Base.
As a result of the outbreak of the Korean War, the United States Air Force's Air Training Command (ATC) reacquired and reactivated the facility, renaming it Pinecastle Air Force Base on 1 September 1951. ATC immediately began a $100 million military construction (MILCON) program at the World War II facility, to include lengthening the existing north/south runway and constructing a parallel north/south runway, both over 12,000 feet in length. Actual flight training operations, however, did not begin until early 1952.
Cambria Air Force Station was one of twenty-eight stations built as part of the second segment of the Air Defense Command permanent radar network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the permanent network. Receiving the Defense Secretary’s approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.