In a major first for NATO research, the NATO Research Vessel (NRV) Alliance has successfully detected the underwater acoustic signature of a ship’s anchor hitting the seabed, marking a significant breakthrough in efforts to protect critical undersea infrastructure (CUI) such as pipelines and data cables.
The detection forms part of a series of operational firsts achieved during Alliance’s month-long mission in the Baltic Sea. These include the ship’s first operations in the waters of Finland and Sweden – NATO’s newest Allies – and the first-time integration of live at-sea data into NATO’s CWIX interoperability exercise in Poland. The campaign, led by scientists from the Centre for Maritime Research and Experimentation (CMRE), is designed to support NATO’s growing need to detect, monitor and deter threats to seabed infrastructure.
“For the first time, we’ve been able to detect an anchor dropping on the sea bottom,” said Dr Robert Been, Principal Scientist at CMRE. “It was a proxy anchor – a ballast mooring – but this is a key step in building the capability to identify and respond to suspicious maritime activity in real time.”
The trial, held off Denmark’s Bornholm Island near the 2022 Nordstream pipeline blast site, used fixed seabed sensors to detect the drop and relay acoustic data. That data was fused with ship tracking information via NATO’s ‘MAINSAIL’ tool, generating an automatic alert when movement suggested possible sabotage. In future, this kind of real-time detection could allow officials at Maritime Command (MARCOM) to be contacted or trigger the launch of an unmanned vessel to investigate the incident at sea.
Dr Been added: “There have been acts of sabotage against critical undersea infrastructure, and we are in the process of trying to assess that problem space. This deployment helps us test and adapt existing technology to address these threats more effectively.”
The anchor drop research supports a wider approach to CUI protection that NATO calls ‘seabed-to-space’ sensing. “We’re trying to understand from an acoustic perspective what an anchor drop looks like,” said CMRE Principal Scientist Dr João Alves. “This is an all-encompassing, data-driven way of looking at the problem – from surface and space sensors all the way to the seabed.”
The Baltic deployment also saw Alliance feed real-time sensor data from unmanned maritime systems directly into NATO’s CWIX testbed via STANAG 4817 – the first time the standard was used operationally to support multi-domain maritime command and coordination.
Based in La Spezia, Italy, NRV Alliance is NATO’s purpose-built, ice capable, global class research vessel, operated by CMRE scientists and crewed by the Italian Navy. As the ship prepares to head north for her Arctic phase, focus will shift to climate and environmental research, as CMRE helps NATO better understand the rapidly evolving conditions of the High North.