Kronstadt, the fourth generation diesel-electric attack submarine (Project 677 or Lada class), is to be launched in 2018. It will become the first ever Russian Air-independent propulsion (AIP) boat. The AIP or anaerobic technology allows to operate without access to atmospheric oxygen (by surfacing or using a snorkel). Kronsdadt will be able to operate submerged for a few weeks without coming to surface. Russian shipbuilding industry has achieved a major technological breakthrough to produce the new sophisticated weapon of war.
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