The second phase of a project to develop underwater surveillance technology is now underway, after the European Defence Agency (EDA) launched the ‘Evaluation of State-of-the-Art Thin Line Array Technology II’ (ETLAT II) over two days from 11 December. With Italy as the lead nation and Leonardo as the lead company, nine members from six European Union Member States are part of the three-year, nearly €4 million project, which aims to strengthen the EU's capabilities in maritime defence.
The project, which launched at Leonardo’s premises in Livorno, aims to enhance ‘Thin Line Array’ technologies for underwater surveillance and anti-submarine warfare. Thin Line Array technologies are underwater acoustic measurement devices used in maritime static and low-speed towed surveillance and monitoring.
Building upon the initial ETLAT project (2015–2018), ETLAT II aims to refine and advance prototypes by addressing unresolved technical problems identified in the first phase. The project focuses on improving operational readiness and finding solutions for the Thin Line Array systems. ETLAT II will draw on advanced numerical models, experimental data, and innovative designs.
Technical objectives: from vibration isolation to testing
Vibration Isolation Systems:
Studying vibrations that affect towing systems, as well as designing isolation solutions to mitigate mechanical disturbances and flow-induced noise, to improve the stability and sensitivity of Thin Line Array systems.
Advanced Numerical Modelling:
Enhancing computational models to predict hydrodynamic behaviour, flow noise, and acoustic performance under various operational conditions, including simulations for different towing speeds and angles.
Experimental Evaluation:
Conducting rigorous prototype testing in controlled environments such as towing tanks and the Lake Nemi acoustic test range – a specialised underwater testing facility near Rome – to validate numerical models and optimise system designs using real-world data.
By integrating numerical simulations with experimental evaluations, ETLAT II aims to increase the Technology Readiness Level (TRL) of Thin Line Array technologies so that they can be reliably deployed in demanding maritime defence applications.
Consortium and Collaboration
- Germany: Bundeswehr Technical Centre for Ships and Naval Weapons, Maritime Technology and Research (WTD 71).
- Finland: Finnish Naval Academy (FNA) and Patria Aviation Oy (Patria).
- Italy: Institute of Marine Engineering - National Research Council (INM-CNR) and Leonardo Spa.
- The Netherlands: Dutch Command Materiel and IT Agency (NL-COMMIT) and Maritime Research Institute Netherlands (MARIN).
- Norway: Norwegian Defence Research Establishment (FFI).
- Sweden: Swedish Defence Research Agency (FOI).
European Defence Agency’s role
The ETLAT II project is conducted within the framework of EDA. Established in 2004, EDA supports Member States in developing collaborative defence capabilities to enhance interoperability and innovation across Europe. By facilitating cooperative initiatives such as ETLAT II, EDA reinforces Europe’s technological edge and maritime security readiness.