The area of the Los Angeles Air Defense Sector (1960–6) and 27th Air Division (1966–69) was adjacent to the 26th, 30th, and 31st Air Divisions at the Four Corners
Activated as the 27 Air Division (Defense) on 7 September 1950, the unit was assigned to ADC for most of its existence,[note 1] the division's initial air defense area was southern California and later southern Nevada (and a small portion of Arizona by 1953).[1]
In May 1958, the 27th AD directed a hostile intercept of a "declared unknown" aircraft (without proper IFF), but the "interceptor pilot remembered...that opening bomb bay doors was to be considered a hostile act only after declaration of an Air Defense EmergencyorWarning Yellow or Red" (the SACB-47 was on a Radar Bomb Scoring bomb run near the Los Angeles Bomb Plot.)[5] The 27th AD was designated 1 of 23 NORAD divisions effective 10 June 1958 by NORAD General Order 6.[5]: 7
In February 1959, the Los Angeles Air Defense Sector was activated during the deployment of the Semi Automatic Ground Environment#Deployment (SAGE) as a subordinate unit of the 27th AD.[7] However, the Denver SCC/CC was cancelled in March 1959; so instead of moving from the Southwest United States to the interior (and the 28th Air Division then taking over as the Southwestern Air Division), the 27th Air Division was inactivated on 1 October 1959 (command transferred to the subordinate Los Angeles Air Defense Sector).
Reactivated in January 1966 at Luke Air Force Base,[1] the 27th Air Division consolidation the Los Angeles and Phoenix Air Defense Sectors, and the division assumed the additional designation of 27th NORAD Region after activation of the NORAD Combat Operations Center at the Cheyenne Mountain Complex, Colorado.[citation needed] The Norton SAGE Direction Center closed in June 1966 (the Luke Direction Center was 1 of 6 still open in 1970).[6]: 47 When the 27th AD was inactivated in 1969,[1] its mission, personnel and operations center at Luke were transferred to the 26th Air Division.[1][8]
^The simultaneous inactivation and organization in February 1952 represents only a change in the type of organization of the division between Table of Distribution and Table of Organization and had no practical effect on the unit.[citation needed]
^ abPreface by Buss, L. H. (Director) (1 October 1958). North American Air Defense Command Historical Summary: January–June 1958 (Report). Directorate of Command History: Office of Information Services. "In May 1958, Western CONAD Region pointed out a weak area in the definitions of a hostile act uncovered in an incident in the 27th Air Division. A B-47 was declared unknown and intercepted, and then was observed opening its bomb bay doors prior to crossing Los Angeles. By the provisions of 55–6, the B-47 should have been declared hostile and destroyed. Fortunately, however, the interceptor pilot remembered the provisions of CONAD 55-3 which provided that opening bomb bay doors was to be considered a hostile act only after declaration of an Air Defense Emergency or Warning Yellow or Red. The actions of the bomber, CFWCR continued, were standard practice for SAC aircraft on radar bomb scoring runs. And when the aircraft was known to be friendly, the practice was not dangerous. However, in cases such as the one in the 27th, the aircraft could possibly be declared hostile and shot down."
^ abcWinkler, David F; Webster, Julie L (June 1997). Searching the Skies: The Legacy of the United States Cold War Defense Radar Program (Report). Champaign, IL: U.S. Army Construction Engineering Research Laboratories. LCCN97020912. Archived from the original on 1 December 2012. Retrieved 23 April 2013. With the exception of a BUIC III at Tyndall Air Force Base, ADC's BUIC III capability was mothballed. ... In 1975, reflecting a structural change in organization, ADC's acronym was changed to ADCOM, the Aerospace Defense Command. ... A reorganization in 1987 placed the site under the Southwest Air Defense Sector of the 25th Air Division. ... Luke-Williams Range/Ajo (A-9/NCC)...In 1961 Luke Range became a SAGE center. ... Z-247/J-29 – Phoenix/Humboldt Mountain/Cave Creek...A detachment of the Luke-based 4629th Air Defense Squadron came to this FAA operated site in late 1972 ... Air Defense Command (ADC) activated a direction center at Luke Air Force Base on 15 June 1959. This center controlled the Phoenix Air Defense Sector until disestablishment in 1966.
^Preface by Buss, L. H. (Director) (1 November 1959). North American Air Defense Command and Continental Air Defense Command Historical Summary: January–June 1959 (Report). Directorate of Command History: Office of Information Services.
Redmond, Kent C.; Smith, Thomas M. (2000). From Whirlwind to MITRE: The R&D Story of The SAGE Air Defense Computer. Cambridge, MA: MIT Press. ISBN978-0-262-18201-0.