The Chilean Navy’s Hydrography and Oceanography Service (SHOA) has obtained a modern Hydrography Vessel LH-02 Defender that will perform soundings of the sea bed to significant depths.
The Chilean Navy’s Hydrography and Oceanography Service (SHOA) has obtained a modern LH-02 Defender-class hydrography vessel to perform soundings of the sea bed to significant depths. The vessel will help SHOA carry out one of its most important tasks: establishing safe navigation routes through the proper mapping of sea floor topography.
“This new vessel has the latest generation hydrography equipment,” said Chilean Navy Rear Admiral Patricio Carrasco, SHOA’s Director. “Hydrography Vessel LH-02 will allow us to describe the sea floor in detail in areas close to the coast, at depths of 10 to 200 meters, by conducting our work in places where it is difficult or risky for larger ships to sail.”
The vessel will allow the Navy to inspect the South American country’s 4,200-kilometer coastline. The LH-02 will complement the existing resources currently handling hydrographic surveys.
Navigation, maritime transportation, fishing and aquacultural activities, water sports, tourism activities, national security and defense, search and rescue operations, maritime boundary delimitation, management and development of the coastal areas, and research in marine sciences, among other activities, “could not be performed with a proper degree of safety if we did not have reliable and up-to-date nautical maps,” RADM Carrasco said.
SAFE Boats International, a U.S. company based near Seattle, Washington, built the vessel at a cost of 405 million Chilean pesos (over $578,000). The General Directorate of Territorial Waters and the Naval Merchant Marine, the parent agency of SHOA, officially christened it on December 11th.
A hydrography vessel is a ship outfitted with equipment designed to conduct bathymetric surveys and complementary environmental observations. It allows for depth measurements in the area of operation and determinations of other factors to describe the marine geography under examination.
Hydrographic Vessel LH-02 is built with an aluminum hull, is 8.2-meters long, and measures 2.6 meters at its widest point. It has a displacement of 3.713 tons and can reach a maximum speed of 46 knots. Its hydrography equipment includes:
Multibundle (swath) sonar: performs a sweep of the sea floor so its geomorphology can be described.
Movement sensor: compensates for errors created by the ship’s movements during operation, resulting in more trustworthy information about the sea floor.
Sounding profile: describes the conditions of the sound wave propagation in water to adjust the swath sonar to conditions at the time.
Side-scan sonar (portable): generates a high-resolution image of sea floor topography, looking at the sides of the navigation route to complement the images recorded by the swath sonar.
These instruments provide detailed information of the sea floor in areas near the coast, which experience variations due to currents, coastal erosion, and seismic activity, which is particularly important to Chile. The vessel must be operated by four seamen: a ship chief; an operator for the system acquiring the hydrographic information; an engineer qualified in the propulsion motors used by Defender-class vessels; and a swath sonar data processor.
Unlike other Navy ships that also perform soundings, this vessel – because of its smaller draft and greater maneuverability – can access and perform soundings in coastal areas that larger vessels cannot enter. Its size and weight allow it to be transported by ground or air, if it cannot navigate to the area it needs to research. Additionally, it can be operated year-round without restriction, even in winter.