India will also take inputs from countries like Russia, which have designed and developed manned underwater vehicles. India will also take inputs from countries like Russia, which have designed and developed manned underwater vehicles.

In three years, when a three-member crew takes off from Indian soil on a one-week journey to explore space, the country may also be ready to send humans into the ocean's depths. City-based National Institute of Ocean Technology (NIOT) is set to develop the country's first manned submersible, which will study unexplored life forms and look for precious minerals and metals spewing out of fissures in tectonically active regions of the Indian Ocean. To develop the submersible, NIOT researchers will team up with Indian Space Research Organisation (ISRO) and use its expertise as some core systems, including a crew module, would be similar to a human space flight. India will also take inputs from countries like Russia, which have designed and developed manned underwater vehicles.
According to experts, the spherical module — 3.2 m in diameter — will be made of titanium that can take a three member crew about 6 km into the ocean to look for metals, minerals and study lesser known life forms. The underwater vehicle, estimated to cost Rs 200 crore, will be part of the ambitious Deep Ocean Mission, which will bring expertise from scientific laboratories in the country together and develop technologies that will be help in the exploration of resources in the ocean.

abyssM Rajeevan, secretary, ministry of earth sciences, said ISRO has agreed to help design and build the crew module for the manned submersible and that a memorandum of understanding will be signed between the two agencies soon.

“We are teaming up with ISRO and trying to have tie-ups with countries like Russia. The capsule may take 18 months. In two to three years, we will have the technology. We will develop the electronics and the mechanical part ourselves simultaneously,” said Rajeevan. "ISRO will design and fabricate since we do not have the technology and it’s tricky. Russia has good technology and they have developed many. So, we will be working parallely with Russia.”

Just like sending humans to space, diving into the depths of the ocean will also put India in an elite club of nations such as US, Russia, France, Japan and China that have conducted manned deep-sea expeditions. ISRO is working towards sending humans to space in 2022.

The submersible will be lowered into the sea from a mother ship, according to experts. The three-member crew will be lying prostrate in the module and perform their task underwater for eight to 10 hours.

NIOT director M A Atmanand said while certain systems that go into the manned submersible may be similar to that of a spacecraft, sending humans into the deep ocean may not be the same as human spaceflight.

“Unlike sending humans into space, which is a vacuum, diving 6000 m into the ocean will increase the pressure about 600 times. Communication with the mother ship will be limited. We will have to use acoustic communication systems. However, ways to maintain oxygen and removal of carbon di-oxide from the module will be similar,” he said. “The crew may require little training as they have to stay crammed. Here, they may be underwater for eight hours. But, contingency measures will be in place for the crew to escape in case of an emergency.”

NIOT will be involved in the designing, integrating, assembling and testing of the submersible.

Scientists have chosen titanium as it has high strength, is tough and has a low density and good resistance to corrosion.

India, at present, is conducting exploration for poly-metallic nodules and poly-metallic sulphides in regions of the Indian Ocean on contract with the International Seabed Authority.

Rajeevan said the submersible would be most helpful when obtaining measurements on the seabed and searching for minerals near hydro-thermal vents which eject minerals along with hot fluids in tectonically active regions like Rodrigues Triple Junction in the Southern Indian Ocean, where exploration is under way.