Lessons from Sweden's Sub Hunt | USNI - Oct. 28, 2014 |

The Swedish navy was pushed into its largest anti-submarine effort since the close of the Cold war last week.

For six days, it hunted for an unknown foreign submersible, likely from Russia, spotted several times off the coast close to the capital of Stockholm.

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Called an intelligence gathering operation--the effort off the coast of Stockholm lasted for nearly a week and included surface combatants, helicopters, ground troops (to sweep the islands in the Stockholm archipelago)--and more than likely one or more of Sweden's air independent propulsion (AIP) attack submarines.

The mystery deepened when Sweden's largest daily, Svenska Dagbladet, reported that the Swedish signals intelligence agency had intercepted emergency communications between a transmitter off the coast of Sweden and Kaliningrad--the home of Russia's Baltic fleet--which suggested that the intruding submarine might be in distress.

A Russian merchant vessel, the NS Concord, circled just outside Swedish territorial waters throughout the operation, leading many to think that it was serving as a mother ship, and that the Swedish navy was tracking the scent of a Russian mini-submarine far inside Swedish waters.

It turns out that Russian submarine found off Sweden is ...

'Sapere aude'