The Naval Science & Technological Laboratory (NSTL) is a premier Indian defense institution and laboratory of the Defence Research and Development Organisation (DRDO), located in Visakhapatnam.
NSTL was established on August 20, 1969, with the core purpose of undertaking research and development of major naval systems and underwater weapons to make the Indian Navy self-reliant. This addressed the problem of dependence on foreign sources for critical naval technology.
The laboratory functions by engaging in the design, development, testing, evaluation, and productionization of underwater weapons and associated control systems. Its key mechanisms involve developing systems like torpedoes (such as the indigenous heavyweight torpedo Varunastra), mines, decoys, and Fire Control Systems. NSTL also investigates hydrodynamic parameters, structural design of naval platforms, and develops Warship Technologies and Stealth Technology for ships. It utilizes specialized facilities, including a High Speed Towing Tank (HSTT) and a recently planned Large Cavitation Tunnel (LCT), the foundation stone for which was laid on April 3, 2026, to boost advanced hydrodynamic research.
NSTL is organized under the DRDO's Directorate of Naval R&D and is closely connected to the Indian Navy, for which it develops systems to meet operational requirements. It also collaborates with Indian industry, such as Bharat Dynamics Limited (BDL), for the production and Transfer of Technology (ToT) of its developed systems. The laboratory's current focus is on achieving Atma Nirbharata (self-reliance) in underwater weapons.