India’s first indigenously-built, nuclear-powered ballistic missile submarine, INS Arihant, is set to begin sea trials shortly India’s The Tribune reported on Sunday, citing unnamed Indian officials.
“The nuclear reactor that will power the submarine can be formally declared ‘critical’ anytime now, while the nuclear-tipped missiles to be launched from underwater are in place,” an unnamed source was quoted as saying.
The sea trials are set to begin in mid-August with the wait being attributed to the rough waters caused by India’s yearly monsoon, which begins to weaken in mid-August according to the source. Once it sets sail the submarine will undergo extensive testing underwater including test launching submarine-launched ballistic missiles.
Once the INS Arihant is ready to conduct deterrent patrols, perhaps as early as the end of this year, India will have at least a nascent nuclear triad—the ability to launch nuclear weapons by land, air or sea.
India is only the sixth country to acquire a sea-based nuclear leg, with the others being the U.S., the UK, France, Russia and China, albeit—as noted last week—Beijing’s ballistic missile submarines are not believed to have conducted deterrent patrols.
India’s quest to build a nuclear-powered ballistic missile submarine (SSBN, in U.S. Navy parlance), reportedly began in 1970 under Prime Minister Indira Gandhi. Code-named the Advanced Technology Vehicle (ATV) program, its existence was kept under wraps for more than three decades ago before the former chairman of India's Atomic Energy Commission, PK Iyengar, revealed it at a public forum back in 2007.
“Indian scientists and technologists are capable of making light water reactors and we are already constructing an LWR at Kalpakkam in south India for the submarine,” Iyengar was quoted by The Guardian at the time as saying.
Russia is thought to have helped design the vessel, although India claims it built the LWR entirely by itself.
The INS Arihant (slayer of enemies) was first launched in 2009 without any corresponding submarine-launched ballistic missiles or the LWR. The vessel weighs 6,000 tons, has a length of 367 feet (110 meters) and reportedly travels at twenty four knots underwater. According to the Tribune, it cost Rs 15,000 crore (appx. US$2.5 billion) to build.
It is powered by an 80-mw pressurized water reactor that uses uranium as fuel and light water as a coolant and moderator. This will allow it to operate quietly and stay submerged for about 2 months at a time.
The SSBN can reportedly carry up to 12 K-15 Sagarika submarine-launched ballistic missiles (SLBMs), that have a range of around 700 km, or 4 K-4 SLBMs, which have a range of 3,500 km and are comparable in many ways to India’s Agni-III land-based missile. The K-4 Missiles are still under development, however. It is also believed to be developing a K-5 SLBM with a range of nearly 1,864 mi.
In 2008, Rear Admiral (retired) Raja Menon was quoted by India Today as saying, “One submarine carries at least 12 [K-15] missiles with Multiple Independently Targetable Reentry Vehicles, which could mean as many as 96 warheads.”
India first announced that it had tested a K-15 SLBM from a submerged pontoon at a depth of 50 meters in January of this year (see video below). At the time it said that it had secretly conducted over a dozen earlier tests of the K-15, and that the development phase was now complete.
Altogether, India plans to field 3 SSBNs with the goal of keeping two on patrol at all times, a highly ambitious plan given needed repairs.
As noted last week, U.S. intelligence reportedly believes that China will deploy its own new SLBM, giving it an effective sea-based deterrent for the first time. Both China and India maintain no-first-use nuclear policies. SSBN's are seen as the most survivable leg of the nuclear triad.