The Hamina class missile boat is a 4-strong class of fast attack craft of the Finnish Navy. Technically they are classified as "missile fast attack craft" , ohjusvene, literally missile boat in Finnish .
When all of the four vessels are finished they will form what the Finnish Navy calls Squadron 2000 (Laivue 2000). The Finnish Navy considered several different compositions for these new squadrons, at one point only two Hamina class vessels and four Tuuli class ACV were to be built. After a strategic shift of the Finnish Navy's role, the composition of the Squadron 2000 followed suit. The prototype of Tuuli class has never been fully equipped, or fitted for operational use, instead two more Hamina class boats have been built. The fourth and final Hamina class ship was delivered in summer 2006.
The squadron should reach its full operative capability in 2008 and will greatly improve the surface- and air patrol as well as air defense capacity. Their electronic surveillance suite will also increase the quality of information available for military leaders.
All ships were built at Aker Finnyards in Rauma, Finland. The vessels have their home base at Upinniemi.
The Hamina class are very potent vessels, boasting surveillance and fire-power capacities, which are usually found in ships twice the size.
The shape of the vessel has been designed to reduce radar signature. Metal parts have been covered with radar absorbent material, and the composite parts have radar absorbent material embedded in the structure. Radar transparent materials (kevlar, balsa) have been used where applicable.
Unlike glass fiber, carbon fiber blocks radio waves. This protects ship's electronics against electromagnetic pulse. In addition, it stops any radio frequency signals generated by ships electronic devices to escape outside. Except for the bridge, the vessel has no windows that would allow the signals to escape.
The vessel contains hardly any steel parts, thus generating very low magnetic field. The remaining magnetic field is actively canceled with electromagnets.
Exhaust gases can be directed underwater to minimize thermal signature, or up in the air to minimize sound in submarines direction. 50 nozzles around the decks and upper structures can be used to spray seawater on the vessel to cool it. In addition, the nozzles can be used to clean the ship after chemical attack or radioactive fall-out.
The Hamina class' primary weaponry is four RBS-15 Mk.3 anti-ship missiles. The vessels are further equipped with a Bofors 57 mm gun against surface and aerial targets as well as the Umkhonto-IR surface-to-air missiles, MASS decoy system and two 12.7 mm heavy machine guns. It is also possible to use the ships for mine-laying.