Editing Lockheed A-12 (section)

===SAM evasion over North Vietnam===
There were a number of reasons leading to the retirement of the A-12, but one major concern was the growing sophistication of Soviet-supplied surface-to-air missile (SAM) sites that it had to contend with over mission routes. In 1967, the vehicle was tracked with acquisition radar over North Vietnam, but the SAM site was unsuccessful with the [[Fan Song]] guidance radar used to home the missile to the target.<ref>{{cite journal |last=Kopp |first=Dr Carlo |title=SNR-75 Fan Song E Engagement Radar / Станция Наведения Ракет СНР-75 Fan Song E |pages=1 |url=http://www.ausairpower.net/APA-SNR-75-Fan-Song.html |publisher=Air Power Australia |date= April 2012 }}</ref> On 28 October, a North Vietnamese SAM site launched a single, albeit unsuccessful, missile. Photography from this mission documented the event with photographs of missile smoke above the SAM firing site, and with pictures of the missile and of its [[contrail]]. [[Electronic countermeasure]]s equipment appeared to perform well against the missile firing.

During a flight on 30 October 1967, pilot Dennis Sullivan detected radar tracking on his first pass over North Vietnam. Two sites prepared to launch missiles but neither did. During the second pass, at least six missiles were fired, each confirmed by missile vapor trails on mission photography. Looking through his rear-view periscope, Sullivan saw six missile contrails climb to about {{convert|90000|ft|m|abbr=on}} before converging on his aircraft. He noted the approach of four missiles, and although they all detonated behind him, one came within {{convert|100|to|200|m|ft|-2|abbr=on|order=flip}} of his aircraft.<ref>{{cite web|title=Pieces of History: Missile Debris from A-12 OXCART|url=https://www.cia.gov/news-information/featured-story-archive/2013-featured-story-archive/pieces-of-history-missile-debris-from-a-12-oxcart.html|archive-url=https://web.archive.org/web/20131028044550/https://www.cia.gov/news-information/featured-story-archive/2013-featured-story-archive/pieces-of-history-missile-debris-from-a-12-oxcart.html|url-status=dead|archive-date=28 October 2013|publisher=Central Intelligence Agency|access-date=2 April 2014}}</ref> Post-flight inspection revealed that a piece of metal had penetrated the lower right wing fillet area and lodged against the support structure of the wing tank. The fragment was not a warhead pellet but may have been a part of the debris from one of the missile detonations observed by the pilot.{{sfn|McIninch|1996}}

The final Black Shield mission over North Vietnam and the [[Demilitarized zone|Demilitarized Zone]] (DMZ) was flown on 8 March 1968. Good quality photography was obtained of [[Khe Sanh Combat Base|Khe Sanh]] and the [[Laos]], [[Cambodia]], and [[South Vietnam]]ese border areas. No usable photography was obtained of North Vietnam due to adverse weather conditions. There was no indication of a hostile weapons reaction and no ECM systems were activated.<ref>{{cite web|title=Black Shield Reconnaissance Missions 1 January – 31 March 1968|url=http://www.foia.cia.gov/sites/default/files/document_conversions/89801/DOC_0001472531.pdf|publisher=Central Intelligence Agency Document Number 0001472531 page 16|access-date=5 April 2014|archive-date=11 February 2013|archive-url=https://web.archive.org/web/20130211185411/http://www.foia.cia.gov/sites/default/files/document_conversions/89801/DOC_0001472531.pdf|url-status=dead}}</ref>{{primary source inline|date=November 2023}}