Italy’s SDO-SuRS programme for underwater operations and submarine rescue support
The new Special and Diving Operations – Submarine Rescue Ship (SDO-SuRS) was launched and named Olterra (A 5321) in a ceremony at T. Mariotti shipyard of the GIN (Genova Industrie Navali) group in the Genova harbour on 9 October 2025 at the presence of Italian Navy, Ministry of Defence Directorate of Naval Armaments (NAVARM), industries and local authorities representatives
The new platform and its mission systems are the response of Italian shipbuilding and underwater industry to the growing demand to support underwater operations and the rescue of submarine personnel in distress, as well as special operations in the maritime context. The SDO-SuRS answers the need of protecting critical underwater infrastructures in the Mediterranean and supporting national, NATO and international operations in the so-called “Wider Mediterranean” area, encompassing the Middle East, Indian Ocean and Western Africa waters.
As an integral part of the renewal process of the Italian’s naval component in this sector, the SDO-SuRS Olterra (A5321) and her organic and deployable mission systems, namely the new generation SAVER (Submarine Assistance, Ventilation & Rescue) suite, are intended to replace the Anteo (A5309) and its equipment, a vessel under the direct command of the Special Naval Group of the Italian Navy COMSUBIN (COMando SUBacquei e INcursori, Divers and Raider Command), engaged in all types of underwater activities, including deep-sea operations and submarine crew rescue, now reaching the end of its operational life after 45 years of service.
The SDO-SuRS programme components
In December 2021, NAVARM awarded the contract for the development, construction, equipment, and provision of in-service support for the SDO-SuRS vessel, to a temporary consortium (RTI) consisting of the T. Mariotti shipyard as agent and prime contractor and the companies Leonardo, Carlo Agnese, and Exa Engineering as principals. In addition to Leonardo, which supplies the vessel’s combat systems, the Drass company, specialized in underwater equipment and vehicles, has developed and provides under separate contracts the suites of organic and deployable systems to be embarked onboard the SDO-SuRS respectively for underwater operations and the intervention, support and rescue of personnel in distressed submarines, namely the next-generation, cutting-edge SAVER (Submarine Assistance Ventilation & Rescue) system, the latter together with Saipem. Carlo Agnese and Exa Engineering, both based in La Spezia, are building the land-based infrastructures that will house an advanced abyssal simulator. Being an integral part of the supply, in addition to faithfully replicating the human-machine interface of on-board diving systems, it will also be able to satisfy the Italian Navy’s needs for testing technologies and methodologies related to unmanned systems intended to operate at abyssal depths, at which human immersion is prohibitive. The contract also includes in-service support for the new vessel and equipment for an initial duration of seven years.
The SDO-SuRS was laid down in April 2023 by T. Mariotti at the CIMAR joint venture shipyard operated together with the steel manufacturer Cimolai group, based in San Giorgio di Nogaro (Udine) on the Northern Adriatic Sea coast. Despite supply issues and delays related to the aftermath of the pandemic and the outbreak of the war in Ukraine, in September 2024 the vessel’s hull with main superstructures up to the flight deck level was towed by tugboats to the T. Mariotti shipyard in the Genoa harbour after being floated using the semi-sinking barge Arcalupa of GIN Maritime Operations.
After the launch ceremony, the shipyard and other companies will finalize ship’s fitting out until the first sea trials in 2026, awaiting delivery in the first half of 2027, thanks also to the strong competence of NAVARM with local office (UTNAV Genova), Italian Navy General Staff and MARINALLES outfitting centre. After this programme, the historic Genoese shipyard with a long experience in complex shipbuilding programmes in the civilian sector, including ultra-luxury cruise ships, mega-yachts and offshore support vessels, was awarded by NAVARM a contract for the first two MTC/MTF (Moto Trasporto Costiero/Moto Trasporto Faro) vessels to support the maintenance of the lighthouse service and maritime signalling, as well as transporting vehicles, personnel, and solid and liquid cargo in national and international waters, along with an oceanographic research vessel ordered by the Ministry of the Environment and Energy Security.
Herafter EDR On-Line readers will find all available details on the SDO-SuRS, subdivided by functional areas, to facilitate reading.
The SDO-SURS platform highlights
SDO-SURS integrated full electric propulsion and dynamic positioning
SDO-SuRS ship electronics, sensors, and combat system
