Navy pitches for slice of nuclear pie with navalised Prithvi

Though the missile in its present form is vulnerable to air and sub-surface threats, it is the first stage in the deployment of a sea-based nuclear deterrent by the Indian Navy which is anxious not to be left behind in the inter-service scramble for the nuclear deterrent.

The other two services already have their Prithvis. The 150-km range Prithvi-I has already been inducted into the Indian Army while the 250-km range Prithvi-II will shortly be inducted into the Indian Air Force.

“The Dhanush represents the navy’s attempt to get a slice of the nuclear pie which will determine additional levels of funding for the armed forces. This will essentially help reserve a role for the navy till the deployment of a ballistic missile armed nuclear submarine,” said a defence official who did not want to be named.

The navy has already modified one of its Offshore Patrol Vessels (OPVs), the INS Subhadra, at the Naval Dockyard, Mumbai to carry the Dhanush. With assistance from Larsen and Toubro (L&T) engineers, the helicopter deck of the ship has been converted into a launch pad. The helo-deck has been strengthened and a hydraulically-stabilised, rail-mounted platform already installed along with a missile erector. Two Dhanush missiles are to be housed in the ship’s helicopter hangar and wheeled out for launch, one after the other. A portable console fitted on board will feed the missile guidance parameters before launch.

The Dhanush is reminiscent of the US navy’s Scorpion programme in the 1950s where a bulky ballistic missile was first test-fired off an aircraft carrier and later fitted on a ship. However, this programme was abandoned after the deployment of a a nuclear powered submarine armed with missiles. The Dhanush is expected to be nuclear-tipped, but like the US navy, India is unlikely to declare whether the missile is nuclear or conventionally armed.

“INS Subhadra was the ideal platform, since it is not a frontline warship and its helicopter deck did not have complicated machinery spaces below,” said a defence official. The 1890-tonne OPV is one of seven such vessels and was bought from South Korea in 1990. These lightly armed ships are used for harbour defence, patrol of offshore installations and patrol of the Exclusive Economic Zone (EEZ), though even an authority like Janes’ Fighting Ships have prophetically noted that these ships have `considerable potential for role change.’

Naval officials have noted that firing a missile from a sea-based platform is the ultimate technological challenge as the ship rolls and pitches and the missile and its systems have to be gyro-stabilised and insulated against the vagaries of harsh saline air.