From K-43 to INS Chakra: a deep dive into general characteristics and operations

The K-43, a Soviet Charlie-class nuclear-powered submarine commissioned in 1967, was assigned to the Indian Navy as INS Chakra in 1988. Despite its brief service in India, Chakra had a lasting impact, helping the country’s later development of Arihant-class nuclear submarines in the 2010s.

The Soviet and Indian navies collaborated to operate K-43, a nuclear-powered Charlie-class cruise missile submarine. The submarine, built between 1964 and 1967, was officially commissioned into the Soviet Navy on November 5, 1967.  K-43 served in the Soviet Navy for a substantial period until being integrated into the Indian Navy and rechristened as INS Chakra in 1988. INS Chakra served in the Indian Navy under its new name until 1991, adding to both countries’ maritime capabilities during its period there. 

General Characteristics:

The Soviet submarine K-43 belongs to the Charlie class, a fleet of cruise missile submarines developed for strategic missions. The submarine, which displaced 4000 tonnes when surfaced and 5000 tonnes when submerged, was 95 metres long, 10 metres wide, and had an 8-meter draft. The propulsion system consisted of a pressurised water-cooled reactor driving two steam turbines, producing an impressive 11,185 kW (14,999 shp) and moving the vessel through a single shaft.

In terms of performance, the K-43 had a surfaced speed of 20 knots (37 km/h; 23 mph) and an enhanced submerged speed of 24 knots (44 km/h; 28 mph). Its operational range was essentially unlimited, restricted only by the availability of food supplies. The submarine had a crew of around 100 people, emphasising its importance as major naval weaponry.

The K-43 had a formidable arsenal. It was armed with eight SS-N-7 Starbright anti-ship cruise missiles, which increased its offensive capability. Additionally, the submarine had six 21-inch (530 mm) torpedo tubes that could launch either 12 torpedoes or 12 SS-N-15 Starfish anti-submarine missiles, demonstrating its versatility in naval warfare scenarios. The K-43’s outstanding specifications and weaponry made it an impressive component of the Soviet naval fleet during its service life.

Operational History:

The Soviet submarine K-43 was built between 1964 and 1967, and it entered service with the Soviet Navy on November 5, 1967. Following its initial duty, the submarine was leased to the Indian Navy, and it subsequently departed Vladivostok on January 5, 1988, for India. The submarine was commissioned into the Indian Navy on the same day it landed at Visakhapatnam, on February 3, 1988. The Indian frigate INS Dunagiri escorted the submarine during its mission, and it was constantly monitored by American and Australian P-3 Orion aircraft.

During its career with the Indian Navy, the submarine, known as Chakra in Indian service, took part in a variety of missions on both the eastern and western fronts. Notably, Chakra participated in the Presidential Fleet Review on February 15, 1989, in Mumbai, which drew great national and international attention. The transfer of the submarine drew widespread media attention, with Time Magazine describing India as an “Awakening Power” and the Washington Post as an “Oriental Bully.”

Contrary to popular misconception, Chakra was only partially manned and controlled by the original Soviet crew while serving in the Indian Navy. Despite Indian appeals and efforts, the Soviet crew allegedly barred access to specific portions of the submarine, including the missile room and reactor compartment. This constraint is thought to have contributed to India’s decision to terminate the lease arrangement after three years of service.

Chakra departed Visakhapatnam on December 16, 1990, for the Soviet Union, accompanied by INS Savitri. The submarine was eventually decommissioned in January 1991. Although the lease period for Chakra was relatively brief, the Indian Navy’s expertise gained during this time was critical in the eventual building of the Arihant class of nuclear submarines in the 2010s.