India is preparing to take a major leap in deep-sea exploration, with two scientists from the National Institute of Ocean Technology (NIOT) set to pilot the country’s first manned submersible early next year. The 28-tonne indigenous craft, Matsya-6000, will initially descend 500 metres off the Chennai coast, a precursor to India’s plan to send humans 6,000 metres below the surface and join a select global cohort capable of such missions.
The aquanauts, Ramesh Raju and Jatinder Pal Singh, will form the core crew of Samudrayaan, the human-rated arm of India’s Deep Ocean Mission under the Ministry of Earth Sciences.
“We have explored the ocean bed at greater depths using remotely operated vehicles. This is for the first time we will be sending humans at a depth of 6,000 metres and safety is paramount for this mission,” NIOT Director Balaji Ramakrishnan told PTI.
The programme is also being viewed as a test of India’s technological self-reliance. Repeated attempts to procure a deep-sea submersible through global tenders hit technology-denial roadblocks, pushing the government to build the vessel domestically.
“We took it up as a challenge. We have the expertise to dive under water, but only up to 1000 metres. Once we embarked on the project and started travelling to allied labs, we found that expertise and technologies were available within the country in laboratories of DRDO and CSIR, and institutes of ISRO,” Ramakrishnan said.
Project leaders say a human presence at those depths will fundamentally expand the mission’s scientific reach. “No camera can match the human eye. It has a different perception that will give a lot of insights to the deep sea floor,” Samudrayaan Project Director Sathia Narayanan told PTI.
Only a handful of nations -- including the US, Russia, China, Japan and France -- currently possess crewed deep-sea capabilities. With Samudrayaan, India aims to join this strategic club even as it moves to harness its 11,098-km coastline and accelerate blue-economy initiatives.
Inside NIOT’s Chennai campus, the Matsya-6000 is steadily taking shape. Its 2.25-metre boiler-steel personnel sphere is fitted into an external frame housing high-density Li-Po batteries, ballast systems, drop-weight escape mechanisms, propellers and emergency buoys integral to its drag-anchor rescue system.
The submersible’s first 500-metre trial dives -- roughly the operating depth of naval submarines -- are planned for early 2026. The ultimate 6,000-metre target is timed for 2027, the year India also plans to launch astronauts into space under the Gaganyaan mission.
For the deeper dives, the current steel sphere will be replaced by a titanium equivalent being fabricated at ISRO’s Liquid Propulsion Systems Centre in Bengaluru. Engineers there have developed an electron-beam welding system to join 80-mm-thick titanium alloy plates capable of withstanding the crushing 600-bar pressure at 6 km depth.
Matsya-6000 will be capable of descending at 30 metres per minute and is equipped with portholes, external lights, robotic arms for sampling, and multiple cameras. Every critical component is undergoing certification by DNV, the global assurance body whose standards are considered the benchmark for underwater safety.
“The DNV certification for every component will make Matsya-6000 one of the safest vessels to undertake deep ocean exploration,” said Sethuraman Ramesh, Group Head, Deep Sea Technology at NIOT.
In August, the two Indian aquanauts completed a 5,000-metre training dive aboard the French submersible Nautile. The experience, they say, is already feeding into operational planning and final design refinements for India’s own deep-ocean craft.
With inputs from PTI