A significant project to install a network of cutting-edge underwater sensors throughout the Indian Ocean Region (IOR) is being progressed by the Indian Navy in cooperation with the Defence Research and Development Organisation (DRDO) and commercial sector partners. The growing number and activity of Chinese research vessels and submarines in the area, which present serious security risks to India’s maritime interests, is the direct cause of this calculated action.
Key marine areas such as the Bay of Bengal, the Andaman and Nicobar Islands, and the Ninety East Ridge will be the focus of the proposed sensor network. These regions are strategically important since they are close to important sea lanes and chokepoints, such the Sunda and Malacca Straits.
China’s research vessel Dong Fang Hong 3 recently conducted a month-long survey of the Ninety East Ridge, a linear underwater structure perfect for submarine navigation, which sparked suspicions about attempts to map the seabed for submarine operations.
A variety of state-of-the-art technologies are anticipated to be incorporated into the underwater sensor systems now in development. These consist of superconducting quantum interference devices (SQUIDs), magnetic anomaly detectors (MAD), and passive and active sonar arrays.
In high-threat scenarios, active sonar devices will offer precise detection and ranging capabilities, while passive sonar will allow for covert, non-intrusive observation by recording submarine noise. By picking up on even the smallest magnetic field perturbations, the combination of MAD and SQUID technologies will improve the detection of submerged metallic objects, like submarines.
Using seabed-based hydroacoustic sensors to track submarine movements from Japan to Southeast Asia, the U.S. and Japan-established ‘Fish Hook Undersea Defence Line’ in the Pacific serves as the model for this project. To essentially establish an early warning system against Chinese submarine incursions into the IOR, India plans to install comparable devices at the northern and southernmost points of the Andaman and Nicobar Islands.
The increasing numerical and technological superiority of the People’s Liberation Army Navy (PLAN), which has a fleet of more than 60 submarines, including cutting-edge nuclear-powered ballistic missile submarines, highlights the urgency of this endeavour. Pakistan’s purchase of eight Yuan-class submarines with air-independent propulsion (AIP) systems from China has further complicated the security situation and given India a two-front underwater threat.
In terms of both quantity and technology, India’s own submarine fleet, which consists of 13 traditional diesel-electric submarines, is currently inferior. The necessity for alternate strategies to strengthen anti-submarine warfare (ASW) capabilities has increased due to delays in the Project 75I program, which aimed to construct six submarines equipped with AIP.
In order to improve India’s underwater domain awareness (UDA) and preserve its strategic leadership in the IOR, it is therefore believed that the creation and use of domestic underwater sensors is essential. A key role in this endeavour is anticipated for the Naval Physical and Oceanographic Laboratory (NPOL) in Kochi, which possesses experience in sonar systems like the Abhay and HUMSA-UG. Prior to these sensor systems being put into service, testing, calibration, and optimisation will be supported by the Ocean Data Centre and DRDO’s Submersible Platform for Acoustic Characterisation & Evaluation (SPACE) facility.
Discussions about combining India’s sensor network with the current US-Japan “Fish Hook” SOSUS (Sound Surveillance System) network are another sign of possible cooperation with Japan and the US. This would strengthen the joint surveillance of Chinese submarine activity in the larger Indo-Pacific.
India has significantly up its efforts to counter the growing submarine threats from China and Pakistan in the Indian Ocean with the deployment of an advanced underwater sensor network. The Indian Navy seeks to protect vital maritime areas, guarantee early detection of hostile submarine activities, and strengthen its strategic position in the area by utilising both domestic technology and foreign collaborations.
There are also indications of potential collaboration with Japan and the United States, with discussions around integrating India’s sensor network with the existing US-Japan “Fish Hook” SOSUS (Sound Surveillance System) network, further strengthening the collective monitoring of Chinese submarine activity in the broader Indo-Pacific.
India’s deployment of an advanced underwater sensor network marks a significant escalation in its efforts to counter growing Chinese and Pakistani submarine threats in the Indian Ocean. By leveraging indigenous technology and international partnerships, the Indian Navy aims to secure critical maritime zones, ensure early warning of hostile submarine activity, and reinforce its strategic position in the region.
