Russian submarine Nerpa (K-152)

INS Chakra
History
Russia
Name	K-152 Nerpa
Namesake	Baikal seal
Builder	Amur Shipbuilding Plant, Komsomolsk-on-Amur
Laid down	1993
Launched	October 2008
Commissioned	2009
Fate	Leased to the Indian Navy for 10 years in 2012, returned in June 2021
India
Name	Chakra
Namesake	Sudarshana Chakra
Commissioned	4 April 2012
Homeport	Visakhapatnam
Status	Returned to Russia, June 2021
General characteristics
Type	Nuclear-powered attack submarine
Displacement	8,140 tonnes (8,010 long tons) surfaced
Length	108.0–111.7 m (354.3–366.5 ft) (sources vary)
Beam	13.5 m (44 ft 3 in)
Draught	9.6 m (31 ft 6 in)

Nerpa (renamed INS Chakra in Indian Navy service) is a 8,140-tonne (8,010-long-ton) Project 971 (or Project 518;^[1] NATO: Akula-class) nuclear-powered attack submarine. The construction of the submarine was started in Russia in 1993, but was suspended due to lack of funding. India then sponsored further construction^[2] and sea trials of the submarine provided it was leased to the Indian Navy for 10 years. It was launched as K-152 Nerpa in October 2008 and entered service with the Russian Navy in late 2009. The submarine was leased to the Indian Navy in 2011 after extensive trials, and was formally commissioned into service as INS Chakra with the Eastern Naval Command at a ceremony in Visakhapatnam on 4 April 2012.^[3] In June 2021 Chakra was spotted on the surface escorted by Indian and Russian warships in the Singapore Strait while presumably heading towards the Russian naval base in Vladivostok; some media speculated that she was returning to Russia before the expiry of the lease term.^[4]

While Nerpa was undergoing sea trials in the Sea of Japan on 8 November 2008, a fire suppression system was accidentally activated, killing 20 civilian specialists and navy crew members and injuring 41 others.