India’s First Manned Deep-Sea Mission: Unlocking the Secrets of the Ocean’s Depths

The Matsya 6000 submersible is set to embark on its maiden voyage in January 2025, with a crew on board, led by scientist Ramesh Raju from the National Institute of Ocean Technology (NIOT) in Chennai. This marks a significant step towards India’s first crewed underwater mission, Samudrayaan.

Raju and a dedicated team of NIOT scientists have diligently prepared for this moment over the past three years. As they approach their litmus test, anticipation mounts. Early next week, the 28-tonne vehicle will undergo trials in a harbor off Chennai, carrying three crew members. If all goes according to plan, NIOT will boldly send a crew 6,000 meters beneath the Indian Ocean in 2026 – coinciding with ISRO’s ambitious manned space mission.

Dr. Vedachalam N, Project Director of Matsya 6000, underscores the significance of NIOT’s role in ocean exploration, drawing a parallel with ISRO’s space endeavors. He emphasizes that the success of the Samudrayaan Mission will propel India into an elite league of nations that have ventured beyond 4,500 meters into the ocean.

This groundbreaking mission heralds a new era in deep-sea mineral exploration and scientific research. It promises to benefit a diverse range of scientific disciplines, including marine biology, mining expertise, oceanography, and climate science, by providing unprecedented access to the unexplored depths of the Indian Ocean.

Vedachalam highlights the unique capabilities of NIOT, asserting that they are the only organization in the country capable of constructing such advanced submersibles. As the sole engineering arm of the Ministry of Earth Sciences, they are poised to lead the way in ocean exploration and innovation.

The Upcoming Wet Test:

The NIOT campus buzzes with excitement and anticipation as the harbor test draws near. From the institute director’s office to the integration facility, where teams collaborate to assemble the Matsya 6000, the atmosphere is electric. The mechanical whirrs and rhythmic hums emanating from the facility attest to the tireless efforts of the scientists and engineers.

The submersible itself is an impressive sight, with its elongated structure, powerful iron rails, and orange batteries. People scurry around it, making final adjustments and ensuring that every cable and setting is perfect.

The lithium-polymer batteries powering Matsya 6000 are a testament to the cutting-edge technology used in its design.

Dr. Ramesh Sethuraman, head of NIOT’s Deep Sea Technology-Submersibles group and leader of the Samudrayaan mission, underscores the importance of the upcoming harbor test. It represents the culmination of various components, bringing together the fruits of their labor.

The test, initially scheduled for mid-December, faced delays due to the Fengal cyclone and challenging weather conditions in Chennai. However, with the all-clear from the India Meteorological Department (IMD), the team is eager to lower the submersible into the 15-meter-deep waters of the Bay of Bengal. The first round of tests will be uncrewed, followed by subsequent crewed missions. The team aims to progressively increase the depth of testing, reaching 100, 200, and eventually 500 meters in the Bay of Bengal before venturing into the allotted Central Indian Ocean region by the end of 2026.

Sethuraman explains that while individual components, such as batteries, propellers, and communication systems, have been rigorously tested, the harbor test will be the first opportunity to evaluate the integrated vehicle in seawater with crew members on board.

Raju, a veteran of over 20 years at NIOT, is tasked with overseeing the electronics and navigation systems of Matsya 6000. With his extensive experience in piloting remote-operated vehicles (ROVs) and autonomous underwater vehicles (AUVs), he is the ideal candidate for this mission. He humbly dismisses compliments, focusing on the task at hand and his upcoming pilot training and medical certification tests.

His colleagues, however, speak highly of his skill and dedication. They recall how, in October last year, Raju and Sethuraman personally tested the human sphere module for Matsya 6000 in the institute’s immersion tank, braving the confines of the underwater chamber for hours.

Annamalai, head of the electrical department for Matsya 6000, underscores the critical nature of their work, stating, “The ocean is not going to give you a second chance – perfection is the need of the hour.”

The Sailors in Suits:

Balaji Ramakrishnan, a key member of the NIOT team, refers to Matsya 6000 as the ‘new kid on the block’ that has captured the world’s attention. The institute, with its rich history of spearheading India’s oceanic adventures for over 31 years, originated from the Department of Ocean Development at IIT Madras in 1993. NIOT has since become an autonomous body under the Ministry of Earth Sciences, serving as its sole technical department for ocean applications.

For many scientists working on Samudrayaan, NIOT’s growth and achievements hold personal and professional significance. Annamalai reminisces about their role in launching ROSUB 6000 in 2010, India’s first remotely operated vehicle to venture beyond 5,000 meters in the Central Indian Ocean. Now, 14 years later, he eagerly anticipates the launch of the first manned mission to reach a depth of 6,000 meters in the same region – a realm more mysterious than the moon.

The dedicated team of scientists working tirelessly on the Samudrayaan mission.

NIOT’s impressive roster of vehicles, including ROSUB 6000, autonomous underwater vehicles, and polar shallow water ROVs, has paved the way for this historic manned mission. The institute’s scientists confidently assert that their extensive experience in submersible technology has prepared them to deliver a crewed submersible for India.

Dr. Balaji Ramakrishnan, director of NIOT, acknowledges the challenges presented by the human element in the mission but assures that they are being adeptly addressed. He emphasizes that while an uncrewed mission would be relatively straightforward, the presence of human crew members adds a layer of complexity that the team is diligently preparing for.

Why Samudrayaan Matters:

The Central Indian Ocean region, where the manned submersible will be deployed, has been exclusively allocated to India by the International Seabed Authority for the exploration of underwater polymetallic nodules (PMNs) containing valuable minerals. These PMNs, spread across 75,000 square kilometers of seabed, are estimated to hold approximately 380 million tonnes of resources, including nickel, copper, manganese, and cobalt.

Vedachalam’s team has designed an innovative system for Matsya 6000, featuring two robotic arms and a ‘sample tray’ to collect and retrieve mineral samples from the seabed. While deep-sea technology institutions worldwide are currently limited to exploration, NIOT is poised to act as India’s deep-sea explorer until mineral extraction becomes economically viable and internationally regulated.

Vedachalam recounts how the idea of building India’s own manned submersible using indigenous technology and expertise gained traction after unsuccessful attempts to procure a vehicle from other countries. He emphasizes that an imported vessel would have presented challenges in terms of operation, management, and maintenance, requiring ongoing international support.

Sitting amidst posters and blueprints of the Matsya 6000 module, Vedachalam proudly highlights India’s Samudrayaan mission as a trailblazer, ushering in the fourth generation of manned submersibles globally. He attributes this achievement to its technological prowess, specifically citing the use of state-of-the-art lithium-polymer batteries as a power source – a first for any country.

The mission control room, from where the submersible’s every move will be monitored and guided.

Vedachalam takes pride in the safety mechanisms incorporated into Matsya 6000, including a search and rescue system capable of locating and retrieving the submersible from the ocean’s depths. He excitedly mentions the ‘digital twin’ system, drawing a comparison to Aishwarya Rai’s twin in the film Iruvar. This digital replica of Matsya 6000 will provide real-time data and insights into the submersible’s performance underwater.

The Impact of Samudrayaan:

At a depth of 6,000 meters, the pressure on the human body will be 600 times greater than at the surface. To withstand such extreme conditions, NIOT scientists have chosen titanium, a strong and corrosion-resistant metal alloy that is lighter than steel or iron. Even the nuts and bolts used in the module have been specially crafted, tested, and certified by an international agency, ensuring the utmost safety and reliability.

Ramakrishnan shares NIOT’s vision for the future of the Samudrayaan mission, which includes building modules capable of reaching even greater depths. He also reveals exciting news: their team, in collaboration with the National Centre for Polar and Ocean Research (NCPOR), has captured the first-ever images of a hydrothermal vent in the Central Indian Ocean ridge, marking a significant milestone in their Deep Ocean Mission.

Embracing the Challenge:

Back at the testing facility, Annamalai, Raju, and Sathianarayanan engage in deep discussion about the module’s ‘personal sphere’. Their combined efforts have resulted in the creation of a human cabin or personal sphere for the crew, ensuring their safety and comfort during the mission.

Vedachalam shares that for the upcoming mission, they are collaborating with their “space cousin” ISRO, who will construct the personal sphere capable of withstanding the extreme pressure and depth of 6,000 meters. This collaboration underscores the synergy between NIOT and ISRO as they work side by side on their respective missions.

As Sathianarayanan meticulously checks the navigation systems, he offers a profound insight: “Fear is good – because if you’re not scared, it means you don’t respect the task ahead of you.”