Rare photos of the 2009-2010 development sea trials of (from top) India's two principal underwater weapon development programmes -- the Torpedo-Advanced Light (TAL) and the Varunastra heavyweight high speed torpedo, developed by the Naval Science & Tech Laboratory (NSTL) in Visakhapatnam. After several stops and starts, theVarunastra is to enter its user trial phase with the Indian Navy this year, while Bharat Dynamics Ltd (BDL), India's principal state-owned missile manufacturer, will begin delivering the first of 25 TALs to the Navy shortly.
Little is known about either programme, mostly because that's the way the government has wanted it. Scant bits of literature (sometimes inadvertent) suggests that technologies involves in both or either of the torpedo programmes include sea water actuated / silver zinc propulsion packages, contra-rotating motor and propellers, proximity sensors, HE warheads, composite material construction, stepless speed control, fibre optic guidance, floating recorder and transmitter (FRAT), noise cancellation techniques and low noise FRP propellers.
