The Kilo and the Improved Kilo classes are diesel electric submarines meant for operations in shallow, coastal waters, and are entrusted with anti-ship and anti-submarine warfare. The Kilo has a reputation for being extremely silent, and extremely difficult to detect. The Improved Kilo class has been feared and respected by NATO sailors. It is nicknamed ‘the Black Hole’ by NATO submariners, a testament to its stealthy reputation.

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