One upon a time there was a defence and intervention frigate

29 March 2021 Defense Naval Group Innovation Story

It was in May 2015, at the aeronautics base in Lann-Bihoué, that the defence and intervention frigate (FDI) programme was officially announced. Five new a defence and intervention frigates (FDI) will take their place alongside the six Aquitaine-class multi-mission frigates (FREMM) and two new Air defence frigates (FREMM DA) to form the French navy’s first-rate defence fleet. With an unrivalled level of digital equipment, the FDI was given a head start right from its construction by the 4.0 fairy godmother. We call this the “digital A to Z”. Is this a modern fable or reality?

Digitised frigate

If innovation and system engineering, from design all the way to maintenance, have given this programme a special identity, the level of digitised systems on board is its other signature characteristic. The FDI is a real innovation in many aspects, from its very specific design (inverted stern bow) to its ultra-modern equipment, but most importantly thanks to the numerous technical and technological breakthroughs in the digital field. “Two data centres host the ship’s software applications, such as those of the combat system management (CMS), platform system management (PMS) and anti-asymmetric threat warfare, as well as cybersecurity management (CyMS)”, explains Sylvain Perrier, FDI Program Director.  “Integrated right from the design phase and over the complete life cycle of its products and services which are made to be resilient, the FDI’s cyber protection system makes it a cybersecured by design frigate.”  

Digital production

The innovation which characterises the programme resides also in the design methods used and those of the management implemented in its operation and the industrial solutions chosen for production. The Naval Group site of Lorient has historically been the birthplace of surface ships and the nerve centre of the FDI programme. It has received investments of tens of million euros in order to renew its industrial tools and increase the yard's efficiency in construction. The production workshops have also been through a digital revolution. Technical drawings in paper have gone: machining work, assembly and conformity tests are now managed with the use of software installed on digital tablets. This move has changed the production trades fundamentally, whilst contributing to the perfect control of product quality and the schedule.

Time management

Naval Group continues to innovate in order to ensure that its industrial and calendar milestones are met. “On-board integration of the ship’s various systems and their sea trials take place with limited lead times, which implies preparation way upstream, explains Sylvain Perrier. A maximum amount of tests for each system to be installed on board take place at land-based integration facilities. Amongst the various land-based facilities used very early on in the programme, the most emblematic of them is the Shore Integration Facility (SIF)." Located at the DGA site of Saint-Mandrier, near to Toulon, this infrastructure was designed for validation tests on the combat system’s performances before installation on board a ship. Also located here is the Panoramic Sensor Integration Facility (PSIF) - a test mast structure identical to the real mast on the future FDI, with its fixed array digital radar, the SeaFire®. Reproducing the FDI combat system on land with the SIF enables the performances to be better characterised and to control the duration of qualification. This system is the ideal illustration of Naval Group’s role as a system engineering leader/Integrator. An important role, one which the group also plans to highlight for export contracts, with a FDI sold under the name of Belh@rra®, after the mythical giant wave observed in the Basque region of France.


  • 24 October 2019: start of manufacturing phase for the first five FDI of the Admirals class (Ronarc’h, then Louzeau, Castex, Nomy and Cabanier)
  • 2023: sea trials of the 1st FDI
  • 2024: delivery of the 1st FDI
  • Before 2030: delivery of the 5th FDI