India’s maritime supremacy in the Indian Ocean hinges on three sophisticated indigenous defence systems. This is the trinity that has transformed the nation’s anti-submarine warfare capabilities: The Hull Mounted Sonar Array-Next Generation (HUMSA-NG), the Maareech Advanced Torpedo Defence System, and the Varunastra heavyweight torpedo.
These systems, developed by DRDO, represent the pinnacle of India’s technological sovereignty in underwater warfare and are a step in the direction of Atmanirbharta in naval defence.
HUMSA-NG: The Navy’s Underwater Eyes and Ears
The HUMSA-NG, part of the fourth generation of indigenously developed ship-borne sonar technology, is the cornerstone of India’s submarine detection capabilities. Designed by the DRDO’s Naval Physical and Oceanographic Laboratory (NPOL) in Kochi, and manufactured by public sector undertaking Bharat Electronics Limited (BEL), the HUMSA-NG has levelled up the Indian Navy’s ability to detect and track underwater threats.
Characteristic of the HUMSA-NG is its ability to easily integrate with other naval systems. This ensures that the system maintains its optium operational efficiency across all frontline warships. The sonar array has already been successfully integrated with the Near-field Acoustic Characterisation System (NACS), enabling real-time performance assessment and calibration aboard naval platforms.
Maareech: The Master of Deception
The Maareech Advanced Torpedo Defence System is India’s answer to one of the most lethal threats in naval warfare: enemy torpedoes. Developed jointly by NPOL Kochi and the Naval Science and Technological Laboratory (NSTL) Visakhapatnam, Maareech focuses on thwarting threats through detection and deception.
When an enemy submarine mounts a torpedo attack, the system kicks into action, detecting the incoming threat using the ship’s hull-mounted sonar systems. Then, it deploys its towed array for continuous tracking. The fiber-optic communication system integrated with Mareech ensures real-time data transmission to the onboard processing unit, which in turn computes the torpedo’s trajectory and impact probability.
Then comes the deception. Based on all these inputs, the expendable decoy system creates false acoustic signatures that confuse the torpedo’s guidance system, forcing it to expend its energy on ineffective courses rather than homing in on the actual target.
Varunastra: The Ocean’s Predator
Named after the legendary weapon of Varuna, the Hindu god of oceans, this ship-launched, electrically-propelled anti-submarine heavyweight torpedo has been designed to target even the most advanced and silent submarines. The formidable weapon can operate in both deep and shallow waters.
The Varunastra weighs approximately 1,500 kilograms and measuring 7.78 metres in length with a 533-millimetre diameter. The torpedo carries a devastating 250-kilogram high-explosive warhead. Its twin-speed capability allows it to achieve speeds of over 40 knots with a maximum operational range of 40 kilometres. Those technical specifications make the indigenously-built Varunastra one of the most capable torpedoes in its class globally.
But, what makes the weapon truly exceptional is its advanced guidance and navigation systems. The torpedo employs active-passive acoustic homing with conformal array transducers that provide wider look angles than conventional torpedoes. Its autonomous guidance algorithms, coupled with GPS/NavIC-based locating aids, ensure precise targeting while the low-drift navigational systems enable long-endurance operations. Remarkably, Varunastra is the only torpedo in the world to incorporate GPS-based recovery systems for practice variants.
The weapon system underwent extensive testing, including over 130 technical trials and 14 user evaluation trials between 2015 and 2016. In June 2023, the Indian Navy achieved a significant milestone by conducting the first combat test-firing of Varunastra with a live high-explosive warhead, demonstrating the weapon’s lethal capabilities against underwater targets.
In a Nutshell
The success of HUMSA, Maareech, and Varunastra has established a strong foundation for future developments in India’s underwater warfare capabilities. DRDO continues to work on advanced underwater sensor networks for the Indian Ocean Region, next-generation sonar systems with enhanced range and resolution, and improved torpedo technologies with greater autonomous capabilities.
The integration of HUMSA, Maareech, and Varunastra into India’s naval fleet beckons the shift from a technology importer to a technology creator.
