India’s only nuclear-powered submarine damaged

India’s only nuclear-powered submarine ‘Chakra’ has suffered “some damage” in an accident and could require substantial repair work to get it back in shape.

The attack submarine, obtained on a 10-year lease from Russia, has not sailed for a month and is berthed at its home port of Visakhapatnam for repairs. 

According to The Print newspaper, the submarine — currently India’s only operational nuclear-powered vessel — suffered damage to its sonar dome in the accident. The sonar dome is located at the forward portion of the submarine, beneath the torpedo tubes. 

While details of the incident are yet to emerge, the newspaper said the damage could be the result of either a collision at sea or accidental scraping while entering the harbour. The Indian Navy refused to comment on the incident, reported The Print. 

Repair work on the submarine is likely to be complicated given that the sonar dome is made of titanium, a difficult metal that requires both specialised machinery and manpower to work on. However, the indigenous Arihant nuclear-armed submarines are also being made in Visakhapatnam and that could help. The Visakhapatnam harbour has recorded incidents in the past when warships have touched the bottom while navigating the tight water channel. In January 2014, the INS Airavat — a Shardul class amphibious warship — suffered damage to its port propeller while entering the harbour. Inducted in April 2012, INS Chakra is a modernised Russian Akula-II class submarine, known as one of the stealthiest in the world after American vessels of similar class. While the submarine is nuclear-powered, it does not carry nuclear-tipped missiles on board and is designed to be a silent killer — it lurks underwater to sink enemy ships and take out land-based targets. 

The stealthy nature of nuclear-powered boats, along with the increasing traffic at sea, has meant that accidents have become common. At least two such accidents had taken place last year itself. 

In July 2016, a British nuclear attack submarine, HMS Ambush, collided with a merchant vessel off the coast of Gibraltar suffering external damage. A month later, the USS Louisiana nuclear missile submarine collided with a naval support vessel at sea, suffering damage to its starboard hull. 

The story behind the Chakra is that it was taken on a 10-year lease in 2012. The Chakra has a displacement of 12,000 tonnes. It is powered by a 190 MW reactor and can reach speeds of over 30 knots. The vessel is manned by 80 crew members and is equipped with tactical missiles, a new fire control systems, sonars and contemporary optronic periscopes and surveillance systems. 

Originally named the Nerpa, the submarine was launched in 1991 but was mothballed after the collapse of the Soviet Union. India later took it on a 10-year lease for close to $1 billion. India is now moving ahead with its plans to lease another nuclear attack submarine from its old ally Russia for an estimated $2.5 billion that will include the refit of the boat at a Cold War era shipyard, followed by a 10-year deployment with the navy. The new ship is likely to be inducted after the completion of the lease period of Chakra.