The ''Sandhayak''-class survey ships are a series of eight vessels built by

Garden Reach Shipbuilders and Engineers Garden Reach Shipbuilders & Engineers Ltd, abbreviated as GRSE, is one of India's leading shipyards, located in Kolkata. It builds and repairs commercial and naval vessels. GRSE also builds export ships. Founded in 1884 as a small privately ...

(GRSE),

Kolkata Kolkata (, or , ; also known as Calcutta , the official name until 2001) is the capital of the Indian state of West Bengal, on the eastern bank of the Hooghly River west of the border with Bangladesh. It is the primary business, comme ...

and Goa Shipyard, Ltd.,

Vasco Vasco may refer to: * Basque language, called ''vasco'' in Spanish * ''Vasco'' (album), a two-part EP by Ricardo Villalobos * Vasco da Gama, Portuguese explorer * Vasco da Gama, Goa, a city in India, often called simply Vasco * Club de Regatas Va ...

for the

Indian Navy The Indian Navy is the maritime branch of the Indian Armed Forces. The President of India is the Supreme Commander of the Indian Navy. The Chief of Naval Staff, a four-star admiral, commands the navy. As a blue-water navy, it operates sig ...

. While ''Sandhayak'', ''Investigator'', ''Nirdeshak'', ''Nirupak'' were built in GRSE; ''Sarveshak'', ''Jamuna'', ''Darshak'', ''Sutlej'' were built by Goa Shipyard.Saunders 2002, p. 316. The vessels equipped with four survey motorboats, two small

boat A boat is a watercraft of a large range of types and sizes, but generally smaller than a ship, which is distinguished by its larger size, shape, cargo or passenger capacity, or its ability to carry boats. Small boats are typically found on inl ...

s and are powered by two diesel engines with a top speed of . They have a helicopter deck and are also armed with a Bofors 40 mm/60 gun mount for self-defense. The ships are equipped with variety of next-generation surveying systems fitted onboard including multi-beam swath echo sounding system, differential

gps The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...

, motion sensors, sea gravimeter,

magnetometer A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, o ...

, oceanographic

sensor A sensor is a device that produces an output signal for the purpose of sensing a physical phenomenon. In the broadest definition, a sensor is a device, module, machine, or subsystem that detects events or changes in its environment and sends ...

s, side scan

sonar Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigation, navigate, measure distances (ranging), communicate with or detect o ...

s, automated data logging system, sound velocity profiling system, digital survey and processing system, amongst others. Working as part of

Indian Naval Hydrographic Department The Indian Naval Hydrographic Department (INHD), headed by the Chief Hydrographer to the Government of India, is an Indian government agency responsible for hydrographic surveys and nautical charting in India. Its headquarters National Hydrogra ...

the ''Sandhayak''-class

survey ship A survey vessel is any type of ship or boat that is used for underwater surveys, usually to collect data for mapping or planning underwater construction or mineral extraction. It is a type of research vessel, and may be designed for the purpo ...

s are equipped with a range of surveying, navigational and communication systems. The ships are designed to undertake shallow coastal and deep oceanic hydrographic survey and collect oceanographic and geophysical data required for the production of digital navigational charts and publications. Besides carrying out their primary role of hydrographic survey, they can also assist in times of war and natural calamities as troop transports and casualty holding ships. The ships are also equipped with ROV,

AUV An autonomous underwater vehicle (AUV) is a robot that travels underwater without requiring input from an operator. AUVs constitute part of a larger group of undersea systems known as unmanned underwater vehicles, a classification that includes ...

& USV. Nirdeshak was decommissioned in 2014.

Service history

was decommissioned on 19 December 2014. The lead ship of the class was decommissioned on 4 June 2021 after 40 years in service. The third ship in the class was decommissioned after 38 years of service on 29 January 2024 in

Visakhapatnam , image_alt = , image_caption = From top, left to right: Visakhapatnam aerial view, Vizag seaport, Simhachalam Temple, Aerial view of Rushikonda Beach, Beach road, Novotel, Novotel Visakhapatnam, INS Kursura (S20), INS ...

Ships in the class

Gallery

Citations

References

External links