The Japan Maritime Self-Defense Force (JMSDF) has announced that it has acquired two types of underwater gliders : The SeaExplorer X2 and the Slocum G3. The systems will be evaluated as the JMSDF is looking for new unmanned underwater vehicles (UUVs) for maritime observation, Naval News reports.
Specifically, the JMSDF has received the SeaExplorer X2 underwater glider from French company Alseamar as well as the Slocum G3 Glider from American company Teledyne Webb Research, the JMSDF document showed.
Both UUVs will be used as test examples for observation of water temperature structure, it also showed.
The service said in Japanese on X on February 23 with photos of those two UUVs: “UUVs are expected to be important equipment for maritime defense. Two test samples of UUVs for ocean observation were recently delivered. We will work to establish an operational framework to enhance the marine observations currently being conducted by the JMSDF.”
According to SeaBreath, Alseamar’s sales representative in Japan, the SeaExplorer X2 is a multi-mission underwater glider that can navigate autonomously without the need for power such as an engine or propeller. The center of gravity is shifted by the internal rechargeable lithium battery moving back and forth and side to side. Any sensor can be mounted on the tip. When it comes to the surface, it communicates with satellites to correct its position and transmit acquired data. Its main features include remote control, data reception, and position correction via Iridium communication. The internal rechargeable lithium-ion battery allows the underwater glider to conduct long-term observations.
Similarly, the Slocum G3 is an autonomous observation vehicle that can measure the profile of the water column (up to 1000m deep) over long distances and for long periods of time by repeatedly ascending and gliding underwater using a buoyancy control mechanism with an oil bladder and a battery center of gravity shift. It is equipped with satellite communication capabilities, so when it ascends to the surface at any time, it can receive mission updates (changes in measurement content, waypoint changes, etc.) and transmit data obtained during the dive via the web-based pilot software. The modular design allows users to use more than 40 types of sensors and optional mechanisms by rearranging them to suit their purpose, according to Hydro Systems Development, the Japanese importer and seller of Slocum G3.
A JMSDF spokesperson told Naval News on March 6 that the service plans to conduct independent research on operational guidelines of both underwater gliders until the end of fiscal year 2025, which is March 2026.
The spokesperson also said that at first it planned to conduct performance tests of those UUVs. But the service changed it to independent research by sailors, taking into account that both underwater gliders are already commercially available products, the spokesperson said.
In addition to the UUVs for observation of water temperature structure, the JMSDF is also considering introducing UUVs for observing seafloor topography and acoustic characteristics survey.
The spokesperson said that the service will sign a contract for research and study on sample selection of those UUVs during fiscal year 2024 ending on March 31, 2025, and that it plans to select that model for the trial product by conducting a survey and research in next fiscal year 2025.
The JMSDF secured 200 million yen ($1.35 million) for research on the entire UUVs for maritime observation during fiscal year 2024.
In order to counter China, which is making aggressive maritime advances, Japan is aiming to strengthen its undersea warfare capabilities, particularly around the strategically significant Nansei Islands, also known as the Ryukyu Islands, near Taiwan and the disputed Senkaku/Daioyu Islands in the East China Sea.
There’s a widespread belief among military experts in Tokyo that in the near future, Japan may use UUVs for mine warfare and anti-submarine operations around the Nansei Islands, including the Miyako Strait between the main island of Okinawa and Miyako Island, a strategically important maritime waterway for China.
