Naval Science and Technological Laboratory

The Naval Science and Technological Laboratory (NSTL) is an Indian defence laboratory of the Defence Research and Development Organisation (DRDO), located in Visakhapatnam. Its main function is the research and development of underwater weapons and associated systems. NSTL is organized under DRDO's Directorate of Naval R&D. The present director of NSTL is Dr. Abraham Varughese and Director General(DG) is Dr Y. Sreenivas Rao, Distinguished Scientist .

NSTL was established on 20 August 1969 to undertake research and development of major naval systems and underwater weapons for the Indian Navy to make it self-reliant.

NSTL is involved in the design, development, testing, evaluation and productionization of underwater weapons and their associated weapon control systems. These include torpedoes, mines, decoys, targets, simulators, Fire Control Systems and weapon launchers.

The lab is also involved in investigating hydrodynamic parameters and structural design of surface and submerged naval platforms and in evolving design criteria through model studies and simulation. NSTL is also involved in developing Warship Technologies, Stealth Technology for ships and Hydro-dynamic research services.

NSTL also develops specialized materials for Marine Applications, including materials for mitigation of Radar, IR, Magnetic, Acoustic and ELFE Signatures leading to stealthier platforms.

NSTL is equipped with laboratories and Hydrodynamic research facilities including a High Speed Towing Tank (HSTT), a Cavitation Tunnel and a Wind Tunnel. They also have Acoustic, Shock, Noise and Vibration Test Facilities that are used to measure, study and analyze the mitigation of underwater noise generated by ships and submarines.

• Maareech ATDS
• Autonomous Underwater Vehicle
• Torpedo Advanced Light Shyena
• Advanced Light Weight Torpedo
• Varunastra HWT
• Shakti Thermal Torpedo
• Takshak Torpedo

DRDO's NSTL in partnership with the Cochin Shipyard is developing the HEAUV autonomous underwater vehicle. The HEAUV, first reported in 2024, is undergoing multiple trials. The vehicle has a weight of 6 short tons (5,400 kg), length of around 10 m (33 ft) and diameter of 1 m (3 ft 3 in). As for the performance, it has a maximum depth of 300 m (980 ft), endurance of 15 days at an economical speed of 3 kn (5.6 km/h) and a maximum speed of 8 kn (15 km/h). It can be mounted with swappable mission-specific payloads. The equipment include:–

• X band 360° surveillance radar for Intelligence, Surveillance and Reconnaissance (ISR) operations, developed by LRDE.
• 45 bar (4,500 kPa)-rated mast mounted radome to house collision avoidance radar.
• Communication systems (including acoustic, UHF, C band, SATCOM).
• Front and flank array sonars as primary underwater sensors, side-scan sonars for mine countermeasure (MCM) operations developed by NPOL.
• Array of batteries for propulsion system which includes electric motors connected to composite propellers.
• Capsule-based hydrogen fuel cell power plant (under development by NMRL.

In the first week of March 2024, the maiden surface trials of the HEAUV was conducted by DRDO and CSL at the International Ship Repair Facility (ISRF) Jetty in Kochi. All the system parameters were met during the trials.

In late March 2025, DRDO conducted Lake Trials of the HEAUV during which vehicle dynamics, in both submerged and surfaced conditions, was tested successfully along with its Sonar and Communications suite.

In 2018, the Ministry of Defence had released a Request for Information (RFI) for the acquisition of eight HEAUVs for Indian Navy's ASW, ISR and MCM operations as well as bathymetric and oceanographic data gathering. Further, an Expression of Interest (EoI) was released to invite Indian companies to develop an HEAUV for just ASW operations. As of now, GRSE is also developing HEAUV-ASW expected to completed by 2027 along with its Neerakshi AUV. Mazagon Dock Shipbuilders also released an EoI for HEAUV-ASW development in 2023.

• DRDO

https://www.drdo.gov.in/labs-establishment/director/naval-science-technological-laboratory-nstl

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