INS Khanderi is the second of the six Kalvari submarines designed in India by the Indian Navy. It is a diesel-electric attack submarine developed by French naval defense and energy company DCNS and manufactured by Mazagon Dock Limited in Mumbai.
With the aim of achieving dominance by raising the underwater presence in the Indian Ocean Region (IOR) with different perceptions of the sea-based threat emerging in the region, the Indian Navy under Project 75 (P-75) took up the production of six Kalvari class (Scorpene) diesel-electric attack submarines (SSKs). And they are being installed at Mazagon Dock Limited (MDL) with the support and technology transfer (TOT) of the French company Naval Group (formerly DCNS).
Overall, various versions of Scorpene-class submarines are found in countries’ navy, including Chile, and in Brazil (with approved production) and in the South Asian field — Malaysia. The P-75 submarine is a well-proven technology that lowers its operating costs in the long term with its indigenization effort.
Since 2015, the first four submarines, christened Kalvari, Khanderi, Karanj, and Vela (names of the former decommissioned submarines) have been under construction and commissioning at MDL in various stages.
More about Kalvari Class Submarine
Kalvari class submarines are pre-conventional stealth propulsion submarines designed for longer ranges while being completely submerged for weeks. These low-noise long-range stealth submarines are force multipliers during wars and serve as invisible deterrence, creating a dominance zone.
During peacetime, the primary role of the submarine is to gather intelligence and special ops, but during hostilities, the submarine will play a crucial role in the tactics of surface warfare against merchant ships/warships and the role of anti-submarine warfare in combating enemy submarines, including mine laying.
The boat’s development is high-tech with a high level of automation in order to minimize the manpower on board. Systems such as PMS provide automated monitoring and control of primary machinery such as PGD (Power Generation & Distribution), Steering, Propulsion & Stabilization System, Safety System, etc. The floating and moving functions on board a submarine are essential to combat capabilities and therefore the PMS system is incorporated seamlessly with the Incorporated Combat System of the submarine. In addition, it is equipped with an acoustic advantage of remaining invisible to enemy sonars to make the boat a formidable weapon against any hostile ship or submarine.
Nonetheless, confirmation measurements on low acoustic signatures etc. are only feasible when Kalvari class submarines are thoroughly tested under various sea conditions (as underwater characteristics are highly unpredictable models varying with seasons, temperature gradient profiles, etc.).
Weapon Punch Onboard
Scorpene submarines feature a large heavy weaponry array, combined with electronic high-tech sensors and guns through the Integrated Combat System. Scorpene submarines are known to be armed with six torpedo launching tubes and precision-guided weapons. Various sonars were installed on board to assist the Arms and Navigation systems (viz. Bow sonar, Stern sonar, Side-looking sonar, Towed array active sonar) to detect threats in shallow and deep waters, including mines.
The Sonar suite outputs are used for various attack / counter-attack steps in the Torpedo Fire Control computers. The submarine uses surveillance radar (when operating at sea surface level) for above water target detection.
Exocet SM-39 Anti-ship Missiles
MBDA SM-39 anti-ship missiles fired by the French EXOCET tube were installed as an integrated kit on board the submarines of the Kalvari Class. These are the Ship launched SSMs submarine variant. Each of SM-39 missiles weighs approx. 655kg, 4.69m long and a diameter of 350 mm.
The missile is housed in a watertight capsule fired from the regular torpedo tube of the submarine and has a solid two-stage propellant. And uses onboard Inertial Navigation system to fly at a sub-sonic speed to the Target location, following a course of sea-skimming.
The SM-39 is an all-time missile with an effective RF seeker’s head to make it a ‘fire-and-forget’ tool. Such missiles can be fired from shallow or deep waters with a high probability of penetration against a heavily defended surface target with a high probability of strike.
Air-independent Propulsion (AIP)
Using an AIP system, a submarine could operate its propulsion electric motor and other electrical systems bypassing traditional battery use, thereby enabling the submarine to stay underwater for a longer period of time (by eliminating the need to surface periodically to take in the air to run diesel engines for charging batteries). The Kalvari class submarine has the provision for AIP fitting to achieve better capabilities; however, the AIP program to be built by DRDO on an indigenous basis has been delayed. With DRDO’s ongoing progress status, the submarine AIP system looks available for implementation only through the submarines‘ next scheduled major overhaul period, which could be after about six years.