paragraph_text: Modern navies that operate such aircraft carriers treat them as the capital ship of the fleet, a role previously held by the battleship. This change took place during World War II in response to air power becoming a significant factor in warfare, driven by the superior range, flexibility and effectiveness of carrier-launched aircraft. Following the war, carrier operations continued to increase in size and importance. Supercarriers, displacing 75,000 tonnes or greater, have become the pinnacle of carrier development. Some are powered by nuclear reactors and form the core of a fleet designed to operate far from home. Amphibious assault ships, such as USS Tarawa and HMS Ocean, serve the purpose of carrying and landing Marines, and operate a large contingent of helicopters for that purpose. Also known as "commando carriers" or "helicopter carriers", many have the capability to operate VSTOL aircraft.

paragraph_text: Initially sensors were optical and acoustic devices developed during the First World War and continued into the 1930s, but were quickly superseded by radar, which in turn was supplemented by optronics in the 1980s. Command and control remained primitive until the late 1930s, when Britain created an integrated system for ADGB that linked the ground-based air defence of the army's AA Command, although field-deployed air defence relied on less sophisticated arrangements. NATO later called these arrangements an "air defence ground environment", defined as "the network of ground radar sites and command and control centres within a specific theatre of operations which are used for the tactical control of air defence operations".

paragraph_text: The "Svea" class was a class of coastal defence ships of the Swedish Navy. The class comprised "Svea", "Göta" and "Thule".

paragraph_text: The "Kearsarge"-class battleships were two pre-dreadnought battleships built for the United States Navy at the beginning of the 20th century. They were designed to be used for coastal defense. Both of the ships, and , were authorized in 1895 and commissioned in 1900. Neither ship participated in a major battle, although they participated in the Great White Fleet, the oldest ships on the cruise. "Kentucky" was decommissioned in 1920 and sold for scrap in 1923. "Kearsarge" was also decommissioned in 1920, although it was then converted into a crane ship, and served in that capacity until scrapping in 1955.

paragraph_text: The British Royal Navy is constructing two new larger STOVL aircraft carriers, the Queen Elizabeth class, to replace the three Invincible-class carriers. The ships will be named HMS Queen Elizabeth and HMS Prince of Wales. They will be able to operate up to 40 aircraft in peace time with a tailored group of up to 50, and will have a displacement of 70,600 tonnes. The ships are due to become operational from 2020. Their primary aircraft complement will be made up of F-35B Lightning IIs, and their ship's company will number around 680 with the total complement rising to about 1,600 when the air group is embarked. Defensive weapons will include the Phalanx Close-In Weapons System for anti-aircraft and anti-missile defence; also 30 mm Automated Small Calibre Guns and miniguns for use against fast attack craft. The two ships will be the largest warships ever built for the Royal Navy.

paragraph_text: USS "Clara Dolsen" (1862) was a large steamer captured by the Union Navy during the American Civil War. She served the Union Navy in river operations and as an "receiving ship" auxiliary.

paragraph_text: Malabar Battery was a coastal defence battery built in 1943 during World War II at Malabar Headland, Malabar, New South Wales, Australia. The battery is also known as "Boora Point Battery".

paragraph_text: In 1943, the Finnish Navy was in great need for new motor torpedo boats and the Finnish ship designer Jarl Linblom studied the Finnish Navy's Italian-designed motor torpedo boats and improved the design. The improved hull design gave them better seaworthiness and the boats could reach up to without armament. Six were manufactured at "Turun Veneveistämö" during the war, and called the "Taisto class".

paragraph_text: To relieve pressure from the expected German attack into Alsace-Lorraine, Napoleon III and the French high command planned a seaborne invasion of northern Germany as soon as war began. The French expected the invasion to divert German troops and to encourage Denmark to join in the war, with its 50,000-strong army and the Royal Danish Navy. It was discovered that Prussia had recently built defences around the big North German ports, including coastal artillery batteries with Krupp heavy artillery, which with a range of 4,000 yards (3,700 m), had double the range of French naval guns. The French Navy lacked the heavy guns to engage the coastal defences and the topography of the Prussian coast made a seaborne invasion of northern Germany impossible.

paragraph_text: When the Winter War broke out the Finnish Navy moved to occupy the de-militarized Åland Islands and to protect merchant shipping. In the first month of the war, battles between Soviet ships and Finnish coastal batteries were fought at Hanko, Finland, Utö and Koivisto. At Koivisto and Hanko, the batteries forced Soviet battleships to retire with damage. Finnish efforts to use submarines ("Vesikko" and "Saukko") to sink Soviet capital ships failed. In December 1939 the ice became so thick that only the ice-breakers could still move. The two coastal defence ships were moved to the harbour in Turku where they were used to strengthen the air-defences of the city. They remained there for the rest of the war.

paragraph_text: "Crosley"-class high speed transports were high speed transport ships that served in the United States Navy during World War II. Some stayed in commission long enough to serve in the Korean War and the Vietnam War. All of them were converted from s during construction except for , which was converted a year after her construction. After World War II ended, several of the ships were sold to Mexico, South Korea, Taiwan, and Colombia.

paragraph_text: Markus Joenmäki is a Finnish professional football defender who currently plays in defence for the Veikkausliiga side FC Lahti in Finland.

paragraph_text: Ilmarinen was a Finnish Navy "Panssarilaiva" ("Armored ship"; a coastal defence ship by British classification). The unit was constructed at the Crichton-Vulcan shipyard in Turku, Finland, and named after the mythological hero Ilmarinen from the Finnish national epic, the Kalevala. "Ilmarinen" was the flagship of the Navy from 1 May 1933 until her demise on 13 September 1941.

paragraph_text: HMS "Bristol" (D23) is a Type 82 destroyer, the only vessel of her class to be built for the Royal Navy. Originally intended as the first of a class of large destroyers to escort the CVA-01 aircraft carriers projected to come into service in the early 1970s, "Bristol" turned out to be a unique ship: the rest of the class were cancelled with the CVA-01 carriers in the 1966 Strategic Defence Review. Following a long career which included the Falklands War, she was converted into a training ship in 1987 and continues to serve in that role. HMS "Bristol" is named after the English city of Bristol.

paragraph_text: 27th (Home Counties) Anti-Aircraft Brigade (27 AA Bde) was an Air Defence formation of the British Army in World War II that served in The Blitz and later converted to infantry.

paragraph_text: The United States Army ship which served in the Pacific Ocean at the end of World War II was named in his honor.

paragraph_text: HMAS "Grantala was a hospital ship operated by the Royal Australian Navy (RAN) during World War I. She was launched in 1903 by Armstrong Whitworth Company for the Adelaide Steamship Company. The ship operated in Australian waters from 1903, and was requisitioned by the RAN on 7 August 1914. She was returned to her owners in 1915, then was sold and renamed Figuig". The ship was scrapped in 1934.

paragraph_text: The Suomi KP/-31 went into serial production in 1931 by Tikkakoski Oy and most of these weapons were bought by the Finnish Defence Forces. The Finnish Defence Forces were equipped with about 4000 Suomi KP/-31 submachine guns when the Winter War started. During the course of the war, the design was altered in February of 1942 with the addition of a muzzle brake, which increased the submachine gun's overall length by 55 mm and weight by half a pound. The revised version was designated KP/-31 "SJR" ("suujarru", or "muzzle brake"). Aimo Lahti was displeased with this revision, believing that it decreased muzzle velocity and reduced the weapon's reliability, and even sought in vain to have the unknown muzzle brake's designer court-martialed. Ultimately, roughly half of the KP/-31s in Finnish service were of the SJR version.

paragraph_text: HMAS "Doomba was a Royal Australian Navy (RAN) warship of World War II. Built for the Royal Navy around the end of World War I as the Hunt-class minesweeper HMS "Wexford, the ship only saw two years of service before she was decommissioned in 1921 and sold to the Doomba Shipping Company. The vessel was renamed SS "Doomba", converted into a passenger ship, and operated in the waters around Brisbane until 1939, when she was requisitioned by the RAN for wartime service. Serving first as an auxiliary minehunter, then an auxiliary anti-submarine vessel, HMAS "Doomba" was purchased outright by the RAN in 1940, and served until early 1946, when she was sold and converted into a linseed oil lighter. "Doomba" was scuttled off Dee Why, New South Wales in 1976.

paragraph_text: USS "Don" (1862) was a captured British steam-operated cargo ship acquired by the Union Navy from the prize court during the American Civil War.

Question: Which war did the operator of the Finnish coastal defence ship Ilmarinen serve in?
Answer: Winter War