- 2 * MTU 16V 538 TB93 diesels, 6600 kW
- 2 * Riva Calzoni IRC 115 waterjets
- Saab 9LV225 Mk4 Combat Management System
- Saab CEROS 200 FCS
- Saab Microwave System Sea Giraffe 9GA 208 Surface search radar
- Raytheon ARPA Navigation radar
- Kongsberg ST2400 Towed sonar
- Finnyards Sonac/PTA towed array sonar
- MASS decoy system
- 1 * Bofors 40 mm/70
- 2 * NSV 12.7 mm machine guns
- 6 * Saab RBS-15 Mk3 SSM
- 2 * Saab Elma ASW-600 9-tube ASW mortars
- Mine rails for tactical mines can be fitted instead of missiles
The Rauma-type missile boat of the Finnish Navy, including Rauma (70), Raahe (71), Porvoo (72), and Naantali, were constructed between 1990 and 1992 at the RaumaHollming / Finnyards Dockyard. The initial price tag for each vessel was approximately EUR 50 million. The most crucial performance aspect of the Finnish Navy's Rauma-class missile ships is their exceptionally shallow draft and lightweight construction, specifically tailored for navigating demanding archipelago conditions. While the shallow draft may not be the most favored characteristic among the crew during rough sea voyages, it does not compromise the vessels' seaworthiness, allowing them to withstand storm surges with tilts of up to 35 degrees.
These ships are crafted from aluminum, ensuring they remain light and maneuverable. Their propulsion system utilizes the Riva Calzone Water Propulsion System, resembling that of jet skis, eliminating traditional propellers or rudders. This system grants the vessels excellent maneuverability and agility in shallow waters. The vessel design takes into account magnetic, electrical, noise, and radar disturbances, with efforts made to mitigate them using various techniques.
The Rauma-class missile boats underwent modernization between 2010 and 2013, with a $70 million renovation conducted at Salon Teijo in the Western Shipyard. This modernization effort involved the renewal of the ships' battle command system and associated weapon and sensor systems. During this process, French Matra Mistral anti-aircraft missiles were replaced with Rheinmetall MASS-decoy launchers.
Patria's coordinated renovation of the Finnish Navy's Rauma-class missile boats is expected to sustain vessel performance until the 2020s. The transition from late 1980s technology to contemporary systems has been remarkable. Over the past few years, Rauma-class vessels have undergone refurbishment, with systems being updated and upgraded. Patria's Systems business held overall responsibility for project coordination and scheduling.
Warships like these typically have a lifespan of about 30-35 years, with Rauma-class ships already surpassing half of that lifespan. Throughout their lifecycle, one overhaul is necessary due to outdated equipment and the unavailability of spare parts for systems manufactured 20 years ago.
The enhanced Rauma-class missile combat center serves as the ship's central intelligence hub. Data from various subsystems provide comprehensive insights into the ship's surroundings, including marine, surveillance, and fire control radar, as well as the video system capturing ship interiors. The underwater listening depth can be adjusted to nearly 200 meters, and an echo meter aids in detecting and locating underwater objects.
A significant compromise during the renovation involved active air defense, which will now rely on a single cannon as anti-aircraft missiles were phased out. Additionally, ships were equipped with gray-matter launchers to deflect radar and heat-seeking missiles using torches or metal chips. Modern echo meters have improved underwater monitoring capabilities. In Rauma-class missile boats, lightness is a critical attribute.
While the conditions in the archipelago pose significant challenges, vessels of this size cannot accommodate very large equipment. Nevertheless, the echo meters' performance remains top-notch globally.
The vessels primarily feature six Saab MTO85M anti-aircraft missiles, along with a 40 mm Bofors anti-aircraft cannon and two anti-aircraft machine guns for ship force protection. For anti-submarine warfare, the ships carry two Saab ASW-600 ELMA Depth Rocket Launchers and Depth Bombs. Kongsberg deep sonar aids in submarine detection, and the vessels are equipped with mine rails for mining missions.
Rauma-class missile boats are predominantly used for personnel training and military exercises at sea, rather than simpler training events on the pier. They also play a role in the operational tasks of the Armed Forces, serving as training platforms for ship personnel. Typically, the ship carries 24 soldiers while at sea, with each crew member assigned specific tasks based on the ship's activities at any given time.