The Mexican Navy (in Spanish, Secretaría de la Marina de Mexico, SEMAR) is a member of Mexico’s federal executive cabinet. Responsible for key hydrographic monitoring of Mexico’s coasts, islands, ports and waterways, SEMAR is also involved in organizing the maritime chart file and the national oceanographic information archive, among myriad other activities.
In 2017, SEMAR acquired a Sonic 2024 for charting purposes, replacing an existing interferometric sonar. Using frequencies of between 200kHz and 400kHz, the Sonic 2024 enabled SEMAR to reach water depths up to 200m – far deeper than previous sonars, which were limited to 50m. “The first time we surveyed with the Sonic 2024, we saw the seabed for the first time,” tells Captain Alcantara. “It’s like we had never seen anything before.”
A portable, integrated solution
Prior to the Sonic 2024, the Mexican Navy had used a multibeam echosounder system for charting. However, the installation had been characterized by a “tangled mess of cables, connections and telecommunications protocols” explains Alcantara. As an integrated solution with very few connections, the R2Sonic was, by contrast, very easy for surveyors to install.
“The Sonic 2024 is a portable solution, which is very convenient for us since we mobilize and demobilize equipment before and after each survey,” adds Alcantara. “It also provides us a lot of flexibility because we can easily ship it from one part of the country to another.”
In addition to charting, the Mexican Navy is also responsible for undertaking surveys for third parties. These surveys are driven by different needs, including dredging, inspections for wrecks and searches for lost objects. Until the introduction of the Sonic 2024, SEMAR had completed its surveys at a single frequency, typically 200kHz, 300kHz or 400kHz. But with the recent acquisition of the multispectral backscatter technical mode, three-frequency surveys in a single pass are now possible.
“We ping at 170kHz, 300kHz and 400kHz,” says Alcantara. “Each frequency tells us something different about the seafloor, and as a result we have greater precision and accuracy in our measurements … It’s a huge gain.” The system’s wide band of operating frequencies have also enabled the navy to build and design IHO-compliant hydrographic charts at a higher scale than ever before.
Rapid data processing, clear imaging
For its data processing needs, the Mexican Navy uses HySweep from Hypack. The cleanliness of the data collected by the Sonic 2024 has allowed the Navy to drastically improve its processing time, emphasizes Alcantara.
“Our data processing time has been reduced by 50%.”
Recently, SEMAR have used TruePix® in surveys where the objective is finding particular features on the seabed. “The resolution and definition of the surveys with TruePix® are second-to-none,” says Alcantara.
To ensure its survey capabilities stay sharp, SEMAR receives regular trainings from both R2Sonic and Seaprod, a distributor of R2Sonic in Mexico. “You never stop learning, even if you operate the system very regularly, like we do,” says Alcantara.
“These regular trainings are very beneficial for us because they enable us to increasingly take full advantage of the capabilities of the R2Sonic MBES.”