The integration of Teledyne Marine’s SeaBat T51-ASV multibeam echosounder into USV FENIX 01 forms part of a collaborative project involving uncrewed vessel manufacturer HydroSurv and subsea services company Subsea Fenix. Read more >>
The 5.7 m battery-hybrid Uncrewed Surface Vessel (USV) combines high-resolution bathymetric survey capability with a modular architecture designed to accommodate a range of hydrographic, geophysical and subsea inspection operations.
Developed by UK-based HydroSurv around Subsea Fenix’s operational requirements, USV FENIX 01 is based on the manufacturer’s REAV-60 platform. The project draws on Subsea Fenix’s experience operating smaller USVs, together with HydroSurv’s vessel design capabilities and Teledyne RESON’s multibeam sonar technology.
Following initial commissioning in August 2026, the vessel entered its first operational phase in Italy, where it collected its first bathymetric data using the SeaBat T51-ASV.
Selecting Multibeam Technology for Uncrewed Survey Operations
Subsea Fenix’s requirements for USV FENIX 01 emerged from its experience conducting more than 400 survey projects. As the scope of its operations expanded, the company identified a need for an uncrewed platform offering greater range, payload capacity and operational flexibility.
Although the vessel represented a new development for Subsea Fenix, the selection of its primary hydrographic sensor built on an established relationship with Teledyne technology.
The company has used Teledyne BlueView sonars since 2013 and was introduced to the Teledyne RESON SeaBat range in 2018 by Codevintec Italiana Srl. This experience provided familiarity with the equipment, data acquisition and processing workflows, calibration requirements and patch-test procedures.
For the new platform, Teledyne worked directly with HydroSurv to integrate the SeaBat T51-ASV into the vessel’s hydrographic survey configuration.
The SeaBat T51-ASV was selected to provide the resolution required for detailed bathymetric surveys while retaining sufficient coverage to support efficient survey missions.
Operating in the 700–800 kHz frequency range, the system provides high-resolution data with coverage of up to seven times the water depth. Its autonomous sonar controls also address an operational consideration for shore-controlled vessels by reducing the number of interventions required at the sensor during survey operations.
Stefano Mancini, CEO of Subsea Fenix, “There was no hesitation over the multibeam. The SeaBat T51 delivers the resolution we were after while maintaining coverage of up to seven times water depth, so the detail does not cost you mission hours.
“On top of that, the T51-ASV’s autonomous sonar controls reduce the number of interventions required on the sensor – a real advantage when you are operating from shore.”
Initial Commissioning and Bathymetric Survey Results
USV FENIX 01 completed its initial commissioning phase in August 2026, achieving Category A under the IMCA M257 framework.
During commissioning, the vessel collected its first bathymetric data using the Teledyne SeaBat T51-ASV, providing an early indication of how the integrated platform performs in operation.
Subsea Fenix has identified environmental monitoring as an initial application for demonstrating the vessel’s operational reliability, alongside a broader strategy targeting pipeline integrity and pre-survey work for offshore energy and infrastructure projects.
Mancini added, “USV Fenix 01 is designed to provide high-efficiency solutions across diverse maritime sectors, starting with environmental monitoring to demonstrate its operational reliability. The broader market strategy focuses on expanding into pipeline integrity and pre-survey applications for various offshore energy and infrastructure projects.
“By utilising uncrewed technology, the platform offers a flexible and scalable approach to data collection that meets the rigorous demands of global subsea industries.”
The development program follows a staged approach, with additional subsea capabilities planned as the vessel progresses through subsequent commissioning categories.
Integration of the launch and recovery system for towed equipment is underway, with Category B under IMCA M257 targeted by the end of 2026. A final development phase is planned for early 2027, when the vessel is expected to progress to Category C and support active ROV and ROTV deployment.
Modular Payload Configurations for Survey and Inspection
A central element of USV FENIX 01 is its interchangeable payload skid architecture, which allows the same vessel to be configured for different survey and subsea applications.
For hydrographic and geophysical work, the vessel can accommodate a survey skid incorporating the Teledyne SeaBat T51 multibeam echosounder. Depending on project requirements, the configuration can also include a sub-bottom profiler, towed side-scan sonar and USBL equipment.
For subsea inspection, an alternative ROV skid incorporates a Saab Seaeye Falcon inspection-class ROV.
The planned launch and recovery system will also allow equipment such as Teledyne Marine’s HydroPACT 660 pipe tracker to be deployed from the vessel.
These interchangeable configurations are intended to allow Subsea Fenix to undertake different types of offshore work using a common uncrewed vessel platform, rather than requiring separate vessels for hydrographic surveying and subsea inspection.
The approach places additional demands on the vessel’s propulsion, electrical and control systems, particularly where precise positioning and low-speed maneuvering are required.
Propulsion and Power Systems for Subsea Operations
The 2026 version of HydroSurv’s REAV-60 platform incorporates twin steerable 11 kW pod drives, providing improved low-speed control and station-keeping capability.
An upgraded power architecture and 48 V electrical system have also been developed to accommodate the operational requirements of the vessel and its interchangeable payloads. These characteristics are particularly relevant to the planned ROV configuration, where vessel positioning and maneuverability must be maintained while supporting equipment deployed below the surface.
The platform has been designed to support ROV operations at depths of up to 300 m, with its propulsion and control systems also supporting the maneuverability and line-keeping required for accurate, repeatable survey work.
Integrating Vessel Design, Survey Technology and Operational Requirements
The project’s interchangeable payload architecture reflects HydroSurv’s approach to accommodating different survey and subsea configurations within a common vessel platform.
David Hull, Funder & CEO at HydroSurv, said, “From the outset, we wanted USV FENIX 01 to be more than a vessel optimised for a single survey application. The REAV-60 platform has been developed around the principle that an uncrewed vessel should be able to evolve as the operator’s requirements change, rather than requiring a new platform for every application.
“That has driven the architecture of USV FENIX 01, particularly the use of integrated, interchangeable payload skids. The vessel’s propulsion, power and control systems have been developed to provide the underlying capability needed to support different survey and subsea configurations, from high-resolution bathymetry through to ROV operations.
“For HydroSurv, the project demonstrates what is possible when flexibility is considered at the platform level. The result is not simply a USV carrying different equipment, but a common offshore platform that can be reconfigured for substantially different types of work.”
From the hydrographic technology perspective, the project involved adapting established multibeam equipment to the operational and integration requirements of a new uncrewed platform.
Pim Kuus, Senior Hydrographer and Product Manager at Teledyne Marine, “This project is a great example of how proven hydrographic technology can be brought into a new generation of uncrewed platforms. Working closely with HydroSurv, we were able to integrate the SeaBat T51-ASV into a vessel designed around the operational requirements of Subsea Fenix, while maintaining the data quality, coverage and efficiency that surveyors expect from the SeaBat range.”
“What makes this project particularly interesting is the combination of HydroSurv’s expertise in designing and adapting the USV platforms with Subsea Fenix’s experience of operating uncrewed systems and Teledyne’s long-established hydrographic technology. It’s a great example of how close collaboration between the vessel manufacturer, technology provider and end user can turn new ideas around uncrewed surveying into practical operational solutions.”
With initial commissioning completed and the first bathymetric data collected, USV FENIX 01 has entered its first operational phase. The planned integration of towed equipment and ROV deployment capabilities will provide further opportunities to assess the vessel’s modular architecture across different survey and subsea applications.
