Operation Atrina was a 1987 Soviet Navy submarine operation, during which five Victor-III class boats - K-244, K-255, K-298, K-299 and K-524 - were deployed from Zapadnaya Litsa base to the Atlantic shore of North America.
The March to May 1987 operation involved taking a longer path around Greenland instead of the usual route via GIUK gap to avoid SOSUS.https://www.usni.org/magazines/proceedings/2020/october/russia-basks-cold-war-glory Developments in Soviet submarine technology - related, among other things, to spy activityhttps://news.usni.org/2014/09/02/john-walker-spy-ring-u-s-navys-biggest-betrayal - further complicated the detection.
Atrina remains a highly debated topic in Cold War history - while Soviet and Russian authors raise it to an almost mythical status,https://dzen.ru/a/ZQvKNdqB0HHqQzJO Western sources claim complex yet successful tracking of at least four boats.https://www.usni.org/magazines/proceedings/2019/october/sub-vs-sub-asw-lessons-cold-war
Multiple media in both Russia and West made connections between Atrina and 2019 Operation Grom, saying the latter was a Russian attempt to break into Atlantics under disguise of Russian Northern Fleet naval training
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