Almirante Cochrane was a central battery ship of the Chilean Navy in the late nineteenth century. She was built, like her twin, Blanco Encalada, in the UK in 1875. She participated in the War of the Pacific, with her most prominent action being her victory over the Peruvian turret ram Huáscar in the Angamos naval battle. Almirante Cochrane was part of the forces that defeated President José Manuel Balmaceda in the Chilean Civil War of 1891.
The ship was named after Thomas Cochrane, a British naval officer who served as the first Vice Admiral of Chile, leading the Chilean Navy during the War of Independence.
Background
In 1871 the president of Chile, Federico Errázuriz Zañartu, initiated a bill in the Chilean congress to authorize the executive to purchase two armored vessels. The bill passed with only one opposing vote (that of the former president José Joaquín Pérez Mascayano), and provided for two medium-sized ships and that the total cost of the purchase would be 2,000,000 pesos.
Construction and operation
The Chilean ambassador to the United Kingdom, Alberto Blest Gana, was placed in charge of the project. Blest Gana hired the British ship designer E. J. Reed, a former naval architect to the British Admiralty, as technical adviser.
The order was placed at Earle's Shipbuilding Co. in Hull, Yorkshire. The central battery ships were to be named Almirante Cochrane and Valparaíso (Valparaíso was subsequently renamed Blanco Encalada). The construction of Almirante Cochrane began in April 1872. The ship was launched and sailed to Chile in 1874, before having been completed, because of fears of a potential conflict with neighboring Argentina and Bolivia. Almirante Cochrane arrived at the port of Valparaíso on December 26, 1874, commanded by Captain Coneyin and returned to the UK to be completed in January 1877, after her sister, Valparaiso had arrived.
In January 1878, once the dispute with Argentina had been settled, President Aníbal Pinto instructed Alberto Blest Gana to arrange for the sale of the two central battery ships in order to alleviate the economic crisis that had prevailed in Chile for several years. On behalf of Blest Gana, E. J. Reed offered Almirante Cochrane to the UK for the sum of 220,000 pounds sterling, but the British declined. Reed then tried to sell the two ships to Russia, but again without success.
She was then rebuilt in 1897-1900 as a gunnery and torpedo training ship. She was scrapped in 1934.
Design
Principal dimensions
Almirante Cochrane was 64.0 m long, with a beam of 14.0 m and a draft of 6.0 m. The hull had a maximum displacement of 3650 t when fully loaded with fuel, fresh water, weapons, ammunition, food and crew. The hull was constructed of iron, held with rivets, and was divided lengthwise into eight compartments (counting piques the bow and stern), by seven iron bulkheads. The bow of Almirante Cochrane had, as was customary in the designs of the late nineteenth century, a sharp spur located under the waterline and projecting ahead of the forward perpendicular. She was fitted with a cruiser stern.
Armament
The main armament, which was mounted on the central redoubt (central battery), was six 228 mm (9 in) Armstrong guns divided by three-band, mounted heal Scott central pivot, allowing the bow cannon to fire off the sleeve. The centerpiece fired at an angle of 70 degrees and 35 degrees to bow to stern and the third from the hose to the stern (see picture). Supplementing this was a 20-pounder cannon, and one 9 and one 7 pounders, and a Nordenfeldt machine gun installed in the COFA's ratchet, one-inch-caliber (25.4 mm), which fired a one-pound (454 grams) projectile.
Almirante Cochrane also had a steam boat which was equipped with a torpedo on a bowsprit. The only time this boat was used was on the expedition to Callao, where she was used to try to sink Peruvian ships.
Armor
The ship was protected under the waterline by an armored belt which stretched from around under the waterline up to the battery cover. The maximum thickness was at the waterline, the center of the ship, and at the bow and stern. The hull and armor plating were separated by a layer of teak thick to reduce the impact of hits. The battery cover, which was flush with the armored belt, was protected by a armour in the center of the ship, reducing to at the bow and stern. The battery, which had a height of between 2 and 2.5 m, was protected in bands and on the front face by two plates, the lower one and the top one thick. The back of the battery was protected by armor plating thick. Like the armor of the hull, this was bolted to a metal structure with an inner lining of teak thick.