Hamina-class missile boat

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" or ohjusvene, literally "missile boat" in Finnish.

History
The vessels were built in the late 1990s, early 2000s, and are the fourth generation of Finnish missile craft. The first vessel was ordered in December 1996 and the fourth was handed over on 19 June 2006. Since the launch of the Helsinki class missile boats, all fast attack craft have been named after Finnish coastal cities. It was previously known also as Rauma 2000 following its predecessor the Rauma class.

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 reached its full operative capability in 2008 and has greatly improved the surface- and air patrol as well as air defense capacity. Their electronic surveillance suite also increases 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.

Design
The vessel's hull is constructed of aluminum and the superstructures are constructed of re-enforced carbon fiber composite. The vessels have a very low displacement and are very maneuverable. They are equipped with water jets instead of propellers, which allow them to operate in very shallow waters and accelerate, slow down and turn in unconventional ways.

The Hamina class are very potent vessels, boasting surveillance and firepower capacities which are usually found in ships twice the size.

Stealth technology


The Hamina class has been designed and constructed as stealth ships with minimal magnetic, heat and radar signatures.

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 escaping 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.

Weapons
The Hamina class have the latest in surveillance and weapons technology all integrated into an intelligent command system. A Hamina class vessel can monitor about 200 km of air space and its Umkhonto surface-to-air missile system can simultaneously engage a maximum of eight aircraft, up to 14&thinsp;km away, while the vessel's anti-ship missiles have a range in excess of 100&thinsp;km.

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&thinsp;mm heavy machine guns. It is also possible to use the ships for mine-laying.

The software of the centralized combat control system is COTS oriented, built on top of Linux running on redundant x86 rack servers, which makes maintenance and future updates and optimizations simpler.

Vessels

 * FNS Hamina
 * Pennant number: 80.
 * Builder: Aker Finnyards.
 * Ordered: December, 1996.
 * Commissioned: August 24, 1998.
 * Home base: Upinniemi.
 * Current status: In active service.


 * FNS Tornio
 * Pennant number: 81.
 * Builder: Aker Finnyards.
 * Ordered: February 15, 2001.
 * Commissioned: May 12, 2003.
 * Home base: Upinniemi.
 * Current status: In active service.


 * FNS Hanko
 * Pennant number: 82.
 * Builder: Aker Finnyards.
 * Ordered: December 3, 2003.
 * Commissioned: June 22, 2005.
 * Home base: Upinniemi.
 * Current status: In active service.


 * FNS Pori
 * Pennant number: 83.
 * Builder: Aker Finnyards.
 * Ordered: February 15, 2005.
 * Commissioned: June 19, 2006.
 * Home base: Upinniemi.
 * Current status: In active service.

Similar ships

 * Houbei class missile boat
 * Skjold class patrol boat
 * Roussen Class FACM