India's second indigenous nuclear submarine is likely to be launched in less than a month's time, towards the end of September or the beginning of October, government sources said.

New Delhi: India's second indigenous nuclear submarine is likely to be launched in less than a month's time, towards the end of September or the beginning of October, government sources said.

Launching of a boat refers to the process of transferring the vessel to the water from a dry dock. Once launched, the boat will undergo extensive sea trials before it is inducted into the Indian Navy sometime in 2019.

The launch is likely to be done by Defence Minister Nirmala Sitharaman in keeping with the tradition that a boat is launched by a woman. The first indigenous nuclear submarine, INS Arihant, was launched in 2009 by former Prime Minister Manmohan Singh's wife, Gursharan Kaur.

INS Arihant was quietly inducted in the Indian Navy in August 2016. It was the first nuclear attack submarine built by a country other than one of the five permanent members of the United Nations Security Council.

Being built under the Advanced Technology Vessel (ATV) project at the Ship Building Centre in Visakhapatnam, the second boat, Aridhaman, will have double the number of missile hatches than its predecessor. It will also be powered by a more powerful reactor than INS Arihant's 83 MW pressurised light-water reactor.

Aridhaman will have a seven-blade propeller powered by a pressurised water reactor and can achieve speed upto 12-15 knots on surface and 24 knots under water.

It has eight vertical launch tubes and can carry up to 24 indegenously-developed K-15 (Sagarika) missiles or eight K-4 missiles. The K-15 has a range of 750 km while the K-4 has a range of 3,500 km.

INS Arihant has four vertical launch tubes and can carry 12 K-15 missiles or four K-4 missiles.

The K-4 missile was developed as the Agni-III missile could not be deployed on INS Arihant due to space constraints.