Launch of the Special and Diving Operations – Submarine Rescue Ship (SDO–SuRS) Olterra (A 5321)
On October 9, 2025, the T. Mariotti shipyard of the GIN (Genova Industrie Navali) group officially launched the Olterra (A 5321), a new Special and Diving Operations – Submarine Rescue Ship (SDO–SuRS). The event, attended by representatives from the Italian Navy, the Ministry of Defence’s Directorate of Naval Armaments (NAVARM), industry stakeholders, and local authorities, marks a significant milestone in Italy’s naval capabilities.
Addressing Emerging Operational Demands
The Olterra (A 5321) is designed to enhance Italy’s underwater operational capacity and address the rising need for submarine personnel rescue and specialized maritime operations. This vessel will play a critical role in safeguarding vital underwater infrastructure within the Mediterranean while supporting national, NATO, and international missions throughout the “Wider Mediterranean” region, which includes the Middle East, Indian Ocean, and Western Africa.
Modernization of the Italian Naval Fleet
The introduction of the SDO-SuRS aligns with Italy’s broader strategy to modernize its naval forces. The Olterra is set to replace the aging Anteo (A5309), which has served for 45 years under the command of the Special Naval Group, COMSUBIN (COMando SUBacquei e INcursori). The Anteo has been integral in executing various underwater missions, including deep-sea operability and the rescue of submarine crews, but it is now nearing the end of its lifecycle.
Program Overview and Contractual Framework
NAVARM awarded the contract for the SDO-SuRS project to a temporary consortium in December 2021. This consortium, led by T. Mariotti as the principal contractor, includes Leonardo, Carlo Agnese, and Exa Engineering. Key components of the contract include:
- SAVER Suite: A state-of-the-art Submarine Assistance, Ventilation & Rescue suite provided primarily by Leonardo and developed in collaboration with Saipem.
- Underwater Systems Development: The Drass Company is responsible for designing and supplying systems for underwater operations and submarine personnel rescue.
- Land-Based Infrastructure: Carlo Agnese and Exa Engineering are tasked with the construction of advanced facilities, incorporating an abyssal simulator that replicates human-machine interfaces used in onboard diving systems.
- In-Service Support: The contract includes comprehensive support services for an initial duration of seven years.
Construction Timeline and Future Prospects
The SDO-SuRS was laid down in April 2023 at the CIMAR joint venture shipyard. Despite facing significant challenges related to supply chain disruptions and geopolitical tensions, the vessel’s hull, along with the main superstructure, was successfully floated and towed to the T. Mariotti shipyard in September 2024 after using the semi-sinking barge Arcalupa.
Following the launch, subsequent fitting out of the ship is scheduled to continue until the first sea trials in 2026, with delivery expected in the first half of 2027. NAVARM’s robust operational expertise, combined with the support of the Italian Navy General Staff and the MARINALLES outfitting center, is anticipated to facilitate this timeline.
Strategic Implications for Italian Maritime Operations
In addition to the SDO-SuRS, T. Mariotti has been awarded further contracts, including the construction of two MTC/MTF vessels to assist in maintaining lighthouse services and maritime signaling, as well as an oceanographic research vessel for the Ministry of the Environment and Energy Security.
This investment exemplifies Italy’s commitment to boost its maritime capabilities, positioning the Olterra as a pivotal asset in addressing both present and future maritime security challenges.
For further details about the SDO-SuRS and its various functional applications, additional resources are available for defense professionals exploring these advancements in maritime defense technology.
