India's boomer

Back in 1991, I wrote what was probably the first article on India's nuclear submarine project also known as the Advanced Technology Vessel Programme in Frontline, a magazine owned by The Hindu group. I had said that the essence of the programme was that India would reverse engineer, with the help of Russian drawings, the Charlie II class of cruise-missile firing Soviet sub. The Indian side, I noted, would design its own 100 MW reactor to power the boat because the Russians were somewhat leery of the NPT, and, more important, the Indians wanted to demonstrate their reactor design prowess.

Tomorrow, Sunday July 26, Harsharan Kaur, wife of Prime Minister Manmohan Singh will launch the Arihant (it cannot be called INS Arihant till it is commissioned a year or so from now) from Ship Building Complex in INS Virbhau, the Indian Navy's shore establishment in Vishakapatnam.

Details made available to me suggest that my original report is essentially correct. The basic design is a Charlie or, as the Soviet designation termed it, Skat. However it has been lengthened another 10 meters from its original 102 meters to accomodate a new module-- a launcher system for the Sagarika ballistic missile it will carry.

It is 10 meters wide and can travel at a submerged speed of 24 knots and will have a complement of 23 officers and 72 sailors.

File picture of INS Chakra, the Soviet Charlie II or Skat 670 nuclear propelled submarine

Its displacement is 6000 tons, though I am not sure whether this is the surfaced or submerged. I do know that at least 500 tons of this is pure ballast because of design problems. This has also slowed the top speed of the boat by about a knot or so.

Russian engineers have been around to help the Larsen & Toubro people build the pressure hull at Hazira. They have also provided help with the reactor. The DAE project failed and so the Russians provided two sets of the VM-5 pressurised water reactor. One was assembled at the Prototype Testing Centre at Kalpakkam and tested with its propulsive machinery. After it was proved, the second was assembled inside a stainless steel shielded shell and taken to Vizag where it was fused into the hull.

The boat was built from 13 sections shipped from Hazira which were then assembled into 3 sections. The first had the sonar and torpedoes, the second the Combat Management System, the living quarters and the ballistic missile launchers, and the third had the reactor and propulsion unit.

The Russians have also been associated with the design and development of the Sagarika a two-stage short ( 700 kms) range submarine launched ballistic missile. The main function of the boomer is to be part of the Indian strategic deterrent. Though it will have secondary weapons like the Klub, tube-launched land-attack missile and torpedoes.

In all liklihood. the construction of the second sub has already begun at the same covered yard in Vizag. But it will be a while before the long-range SLBM , an Agni derivative will be based on the boomer.