India's indigenous N-sub secret is out

The Defence Research and Development Organisation (DRDO) has added a feather to its cap. It is delivering on schedule— in 2009— India's first indigenously built nuclear powered submarine (SSBN) as it had promised at the beginning of the United Progressive Alliance's (UPA) term in office.

The secret of the indigenous nuclear submarine programme seems to be finally out. Defence minister A. K. Antony has confirmed what was being speculated all this while - that the country is ready to launch the third arm of its nuclear triad.

India is getting a batch of submarine launched ballistic missiles (SLBM) and submarine- launched cruise missiles (SLCM), ready to wed with the SSBNs, which would presumably be nuclear tipped. This would, in turn, underline the deterrence posture of the nuclear weapons programme providing it a failsafe 'second strike' capability.

But this would also entail fundamental change in the country's nuclear weapons policies for the peculiar nature of nuclear submarine deployment.

A nuclear submarine remains submerged underwater for most of its deployment period thus making communication difficult especially in times of a national emergency.

A nuclear submarine commander is therefore armed with a separate launch regimen that is qualitatively different from those used above ground.

Hence, when India launches its nuclear submarine, reportedly three, it would have to put in place launch codes that would provide a degree of autonomy to the commanders. This, in turn, would change the deployment pattern of at least a portion of the country's nuclear forces to 'ready arsenal'. This would require a political decision.

The Indian development is important in terms of the changing Chinese deployment by which they are modernising their nuclear submarine fleet, putting into waters the refurbished Xia class and a new Jin class.

The country had been working on the submarine, coyly termed Advanced Technology Vehicle (ATV) since 1985. The design is reportedly based on the old Charlie II- class submarine - a former Soviet make.

The programme was bedevilled with problems in developing a reactor suitable for the platform and then, building a containment vessel for the reactor. The attack submarine design is said to have a 4,000- ton displacement and a single- shaft, home- built nuclear power plant.

The estimated speed of the vessel is 12- 15 knots on surface, and 30- 34 knots submerged.

The reactor is of the pressurised water variety.

The nuclear submarine would beef up the country's presence in the Indian Ocean.

It brings to fruition a programme that was kicked off under the leadership of the late Rajiv Gandhi who had leased a Charlie- class nuclear submarine that was renamed in 1988 as INS Chakra.