In a historic achievement for India’s deep-sea exploration program, two Chennai-based aquanauts from the National Institute of Ocean Technology (NIOT) have successfully completed the country’s first manned dive to depths nearing 5,000 metres in the North Atlantic Ocean.
The feat, accomplished aboard the French deep-submergence vehicle Nautile, marks a crucial preparatory milestone for Samudrayaan, India’s upcoming deep ocean mission that will send the indigenous Matsya 6000 submersible to 6,000 metres by December 2027.
On August 4, former Indian Navy Commander Jatinder Pal Singh reached a record depth of 5,002 metres, while fellow aquanaut R Ramesh descended to 4,025 metres on August 5. Both dives were closely monitored by three other scientists aboard the support vessel. Using a robotic arm, the team placed the Indian flag on the ocean floor, symbolising India’s entry into an elite group of fewer than six nations to have ventured to such depths.
Commander Singh spent nearly 10 hours on his mission, with half the time dedicated to descent and ascent. His tasks included collecting seabed samples, testing emergency ascent procedures, and assessing life-support systems under simulated failures. “At that depth, there is no sunlight. We trained with and without lights,” he said. Singh, who has logged over 3,000 diving hours, also holds a record 670-metre dive and has participated in 11 submarine rescue missions.
Ramesh, an experienced remotely operated vehicle (ROV) pilot, described the dive as “seeing through our eyes what we earlier only saw through cameras.” His five-hour expedition involved navigation, inspection, and seabed sampling.
Union Minister Jitendra Singh hailed the achievement as part of India’s “double conquest” of unexplored frontiers, highlighting the nation’s simultaneous strides in space and deep-sea exploration. Ministry of Earth Sciences Secretary M Ravichandran confirmed that the expedition, conducted with France’s Ifremer, provided critical hands-on training for the Samudrayaan crew in piloting, robotic operations, and acoustic communication.
The Matsya 6000 submersible, designed to endure crushing pressures of 600 bars with a 96-hour endurance capacity, has completed harbour tests in Chennai and will undergo shallow water trials in 2026. A special ship equipped with a 27-tonne crane is being built to launch the submersible.
NIOT Director Balaji Ramakrishnan expressed confidence in India’s readiness: “Every component is being engineered for extreme conditions. Very soon, our indigenous Matsya will take the dive to 6,000 metres.”
With this milestone, India edges closer to harnessing deep-sea resources and securing its place among the world’s leading ocean-exploring nations.
