The Finnish Navy’s Hämeenmaa-class minelayer FNS Uusimaa looks set to undergo a complete main engine replacement programme in order to sustain the vessel until the planned replacement Pohjanmaa-class corvettes enter service later in decade.

In a contract notice posted on the European Union’s tender website, the award of the deal to Wärtsilä Finland Oy will see the company install two engines in replacement of the existing Wärtsilä Vasa 16V22 diesel engines fitted to the FNS Uusimaa.

The existing engines drive two controllable pitch propellers, delivering a total combined power output of 2,600kW to enable a maximum speed of 20 knots.

According to the contract notice the start date for the engine replacement is listed as 29 February 2024, and is due to be completed by 30 September 2025. The contract was awarded without competition, as Wärtsilä Finland Oy provided the legacy propulsion system and the planned replacement.

In the contract justification, it was stated that the FNS Uusimaa “is a critical vessel of the [Finnish] Defense Forces”, the use of which “must be secured until the operational use of the LV2020 [Pohjanmaa class] vessels”.

The use of original spare parts and the manufacturer’s maintenance planning guaranteed “the best possible life cycle management… as cost-effectively as possible”.

It is not known which marine diesel engines will be provided to replace the existing Wärtsilä Vasa 16V22 diesel models, which have since ceased production.

Hämeenmaa-class minelayers

Designated as coastal minelayers, the two-ship Hämeenmaa-class are effectively multi-role patrol corvettes, featuring a variety of armaments installed, including a 57mm Bofors main gun and an eight-cell Umkhonto-IR SAM vertical launch system. The Umkhonto-IR missile has an operational range of 12km and uses an all-aspect infrared, command update fire and forget guidance system.

The class is also equipped with two RBU-1200 ASROC (anti-submarine rocket) launchers for attacking subsurface threats such as submarines. In addition, the Hämeenmaa-class vessels have four mine rails off the stern of the ship, able to fit 100-150 mines.

In December 2006, the Finnish Navy signed a contract with Rheinmetall Waffe Munition for two MASS decoy systems, with the class also using the Thales DR3000 SIEWS (shipborne integrated electronic warfare system) for electronic warfare capability.

The keel for the lead ship in the class, FNS Hämeenmaa, was laid down in April 1991 and commissioned in April 1992. The second and final vessel, FNS Uusimaa, was laid down in November 1991, launched in June 1992 and commissioned in December 1992.

The class has a length of 77 metres and displaces 1,450 tonnes, accommodating a crew of 60 personnel.

Pohjanmaa-class corvette

In October last year, Finland’s naval manufacturer Rauma Marine Constructions (RMC) cut steel on the country’s first Pohjanmaa-class corvette, finally beginning the construction phase of the €1.23bn ($1.36bn) ‘Squadron 2020’ programme to replace the Finnish Navy’s legacy seven-ship fleet, after some delays.

Finland’s Defence Forces Logistics Command signed the shipbuilding contract with RMC for four Pohjanmaa-class corvettes in September 2019.

According to Finland’s MoD, construction will continue until 2029. In April, the Government issued a call for technical experts to join the build, citing “delays in the initial build phase” of the project. The first-in-class vessel is planned to be operational by 2027.

Additional reporting from John Hill.