Rivadavia class battleship
Encyclopedia
The Rivadavia class was a two-ship group
of battleship
s (Spanish: acorazados) designed by the American Fore River Shipbuilding Company
for the Argentine Navy
(Armada de la República Argentina). Named and after important figures in Argentine history, they were Argentina's counter to Brazil's two Minas Geraes-class battleships
.
In 1904, Brazil scrapped a previous naval building program in favor of an order that included two dreadnought
s, despite signs that such an action would spark a South American naval arms race
. To counter this acquisition by a major rival, Argentina began seeking bids for at least two dreadnoughts in 1908. Over the next two years, multiple shipbuilders from five countries vied for the contracts, complemented by efforts from their respective governments. Argentina was able to play this hyper-competitive environment to its own advantage by rejecting all of the initial proposals and calling for new ones that required the best aspects of each. They then repeated this process, despite complaints from shipbuilders that their trade secrets were being given away. The contracts were awarded to the lowest bidder, Fore River, in early 1910. This move shocked the European bidders, but could largely be explained by the American steel trust's ability to produce steel at a much lower cost than any other country.
During their construction, the Argentine battleships were frequently subject of rumors involving their sale to a foreign country, especially after the beginning of the First World War
. Under diplomatic pressure not to sell, Argentina kept the two ships. Throughout their careers, Rivadavia and Moreno were based in Puerto Belgrano
and served principally as training ships and diplomatic envoys. They were modernized in the United States in 1924 and 1925 and were inactive for much of the Second World War
due to Argentina's neutrality. Struck from the navy lists on 1 February 1957, Rivadavia was scrapped
in Italy beginning in 1959. Moreno was struck on 1 October 1956 and was towed to Japan in 1957 for scrapping in what was then the world's longest tow (96 days).
and control of the Beagle Channel
going back to the 1840s. It nearly led to war in 1878 and kindled a naval arms race from 1887 to 1902 which was only settled via British mediation. As part of the three pacts
which ended the dispute, restrictions were placed on the navies of both countries. The British Royal Navy
bought two pre-dreadnought
battleships that were being built for Chile, and Argentina sold its two Rivadavia-class
armored cruiser
s under construction in Italy to Japan. Meanwhile, beginning in the late 1880s, Brazil's navy fell into obsolescence after an 1889 revolution, which deposed Emperor
Dom
Pedro II
, and a 1893 civil war
. By the turn of the 20th century it was lagging behind the Chilean and Argentine navies in quality and total tonnage, despite Brazil having nearly three times the population of Argentina and almost five times the population of Chile.
By 1904, however, Brazil began to seriously consider upgrading its navy to compete with Argentina and Chile. Soaring demand for coffee and rubber
brought the Brazilian economy an influx of revenue, which paid for a $31.25 million (in 20 dollars, $) naval repair scheme, a substantial amount for the time period. The bill authorized 28 ships, including three battleships and three armored cruisers. It was not possible to lay down the battleships until 1906, the same year the trend-setting was constructed. This ship prompted the Brazilians to cancel their battleship plans in favor of two Minas Geraes-class
dreadnought
s. The ordering of these powerful ships—designed to carry the heaviest armament in the world at the time—shocked Argentina and Chile. Historian Robert Scheina comments that the dreadnoughts alone "outclassed the entire [elderly] Argentinian fleet."
Debates raged in Argentina over the wisdom of acquiring dreadnoughts to counter Brazil's. The National Autonomist Party
cabinet was in favor, despite a probable cost of over $9.74 million (in 20 dollars, $), but a specific plan for two 14000 long tons (14,225 t) battleships and ten destroyers was not popular with the public. Alarmed, the American ambassador to Brazil sent a cablegram
to his Department of State
, warning them of the destabilizing effects that would occur if the situation devolved into a full naval arms race.
Despite American entreaties to preclude the naval arms race, Brazil continued development on the ships. This, combined with renewed border disputes, particularly in the River Plate
(Río de la Plata, literally "Silver River") area, spurred Argentina to move forward with plans for their own battleships. Inflamed by newspaper editors, the public was now fully supportive of a naval building program. While an early plan called for $35 million to be invested—$7 million from foreign loans—a $55 million (in 20 dollars, these numbers are (respectively) $, $, $) plan was adopted in August 1908. Hoping to end the arms race, Argentina made an offer to purchase one of the two Brazilian ships, but the refusal prompted the dispatch of an Argentine naval commission to Europe to acquire dreadnoughts.
Proposals from shipbuilders for two dreadnoughts (along with a possible third, to match Brazil should a third ship be ordered) and twelve destroyers were solicited in 1908 by open tender. In order to ensure that the designs reflected the most modern practices, the requirements were intentionally vague.
Fifteen shipyards from the United States, Great Britain, Germany, France, and Italy began bidding on the battleships. Diplomatic pressure to give the contracts was brought to bear from all these countries, especially the first three. Even with this assistance, industry leaders in the United States believed that they had no chance in the bidding without active cooperation from their government, as Europe was the traditional arms supplier to Argentina (and to all of South America). Even when this was given, including the removal of import tariffs on hides
from Argentina, promises for additional concessions if American shipbuilders were selected, and an offer to include the most technologically advanced fire-control system
and torpedo tube
s available on the Argentine battleships, the United States was widely viewed as a non-contender. Historian Seward W. Livermore remarked:
The president of the Newport News Shipbuilding and Drydock Company believed that the United States would not receive contracts due to what he saw as a large amount of European meddling in Argentina:
The United States, however, found an ally in Buenos Aires' main daily newspaper, La Prensa
. The owner, editor, and naval editor were all in favor of acquiring American-designed dreadnoughts. In addition, the paper found evidence of British wrongdoing in a related naval contract. Under public pressure, the naval commission was forced to reconsider its original list, which had placed Italy first and Britain second. It now featured the United States first, Britain second, and Italy last.
In a surprise move, the Argentine naval commission then threw out all of the opening tenders and called for another round of bidding; they simultaneously updated the specifications to include what were judged to be the best aspects of all the plans. The competitors were given three weeks to come up with new designs and cost estimates. After diplomatic protests, this was modified slightly; the original bids were kept, but alterations to attempt to conform to the new desired characteristics were allowed.
The commission found that the Newport News Shipbuilding and Drydock Company bid was lowest on one battleship, and the Fore River Shipbuilding Company
was lowest on the other. Despite a British attempt to allow the Armstrong Whitworth
-Vickers
team to lower their price by $570,000, prompt American diplomacy granting various assurances regarding recent events between the United States and Brazil, the upcoming 1910 Pan-American Conference
, and a guarantee of American participation in the Argentine centennial celebrations secured the battleship contracts for Fore River on 21 January 1910. The maximum price Fore River tendered, $10.7 million (in 20 dollars, $), underbid the British by more than $973,000. Italy's tender was just $48,600 more, but their ship's displacement
was 2000 long tons (2,032 t) smaller, the belt armor
was 2 inches (50.8 mm) thinner, and the top speed was slightly slower.
Rivadavia was built by Fore River at its shipyard in Massachusetts; as called for in the final contract, Moreno was subcontracted
out to the New York Shipbuilding Corporation
of New Jersey. The steel for the ships was largely supplied by the Bethlehem Steel Company of Pennsylvania, which, due to their ability to produce steel at a lower price than other nations, was an integral cost-saving measure. The Secretary of the Argentine Naval Commission, the body which chose the final design, said the reason the American tender was lower than that of the English was that "steel for construction work and armor-plating is a great deal cheaper in the United States than in England. Wages are higher there, but the contractors ... are able to obtain it more cheaply owing to the manipulations of the Steel Trust."
A third dreadnought, provided for in the contract, was strongly supported by Argentina and by U.S. diplomats during 1910, while the Minas Geraes class was still under construction. La Prensa and one of its rivals, La Argentina
, heavily advocated a third ship; the latter even started a petition to raise money for a new battleship. An American diplomat wrote back to the United States that "this newspaper rivalry promises the early conclusion of a movement which means a third battleship whether by public subscription or by Government funds." However, Brazil's 21–26 November Revolta da Chibata
("Revolt of the Whip"), in which the three most powerful ships in the fleet (the battleships , , and the cruiser ) along with an older coast defense ship (Deodoro) violently rebelled, crushed the previous sentiment for a new battleship. About two years later in October 1912, a third dreadnought was authorized by Argentina in case Brazil's Rio de Janeiro
was completed and delivered. The ship was never named or built, as Rio de Janeiro was sold to the Ottoman Empire
due to monetary issues, and a later planned Brazilian ship was canceled due to the beginning of the First World War
.
Various British newspapers also cried foul. The Evening Standard
believed that as "Argentina's greatest creditor and greatest client", Britain ought to have been awarded the two ships. The Times
took a different track, accusing American shipbuilders of slashing prices to an obscene degree, and accusing the government of exerting undue diplomatic pressure to obtain the contracts.
New Zealand's Evening Post
noted that the United States had previously built major warships for other countries, including Russia's and Britain's ally Japan, and commented, "The severity of the blow to England rests in ... the amount of English capital in [Argentina]", possibly echoing the Evening Standards argument. They referred to a "startling" fact printed by the Daily Mail
: the steel used for the armor of the American design was obtained for a much lower price. With Bethlehem's ability to produce it at £8 less per ton than British foundries, a cost savings of more than 10% in steel over the British ship could be realized.
Germany asserted that the United States was given the opportunity to view the other nations' tenders and lower their price accordingly. Germany also alleged that the United States had secured the deal by pledging to come to Argentina's defense should they become embroiled in a military conflict.
The New York Times noted that with Argentina's and Brazil's dreadnought orders, countries in North and South America were building the five biggest capital ships in the world (Brazil's Rio de Janeiro, Argentina's Rivadavia and Moreno, and the United States' and ) in addition to seven of the ten largest (including the United States' and ). Shortly after Rivadavia had completed her trials, the U.S. Navy's Board of Inspection and Survey
remarked that she "handle[d] remarkably well ... with comparatively minor modifications the vessel would practically meet the requirements of our own vessels." The Board of Inspection was less pleased with the wing turrets, stating that "while theoretically the Rivadavia has an ahead and astern fire of six guns, this is not so in reality, as it is almost certain that the blast from the waist turrets would dish in the smokepipes and damage the uptakes."
Three bills directing that the battleships be sold were introduced into the Argentine National Congress
in the summer of 1914, but all were defeated. Still, soon after the beginning of the First World War, the German ambassador to Argentina alleged to the U.S. State Department that Britain's Royal Navy was going to take over the ships as soon as the ships reached the River Plate, and the British put diplomatic pressure on the United States to try to ensure the ships were not sold to any other country (as this new country could in turn sell them to Germany). Italy, the Ottomans, and Greece were all reportedly interested in buying both ships, the latter as a counter to the Ottoman purchase of Rio de Janeiro. The United States, worried that its neutrality would not be respected and its technology would be released for study to a foreign country, diplomatically pressured Argentina to keep the ships, which it eventually did.
of fourteen 12 inches (304.8 mm) guns in dual turrets (two superfiring
fore, two wing, and three non-superfiring aft), a secondary battery of twenty 4-inch (102 mm) guns and four torpedo tube
s on a hull of 22000 long tons (22,353 t) that would be capable of 21 kn (25.6 mph; 41.2 km/h). Foreign practices also bore a large influence on the design; most were acquired through the unique design process of rejecting multiple bids and calling for the best aspects of each. For example, the superfiring arrangement of the main battery was an American innovation, while the wing turrets were similar to British designs of the time. The secondary battery of 6-inch (152 mm) guns and the three-shaft system were influenced by German design practices, while the engine and boiler layout was reminiscent of the Italian battleship .
, the first president of Argentina
, and was built by Fore River Shipyard
. She was laid down on 25 May 1910, launched
on 26 August 1911, and completed in December 1914. was named after Mariano Moreno
, a member of the first Argentine government in May 1810, and was built by New York Shipbuilding Corporation. She was laid down on 10 July 1910, launched on 23 September 1911, and completed in February 1915. Both ships had engine trouble soon after completion: Rivadavias completion was delayed due to a damaged turbine, while Moreno had an entire turbine fail while on her trials.
The ships finally arrived in Argentina in February and May 1915, respectively. In the early 1920s, both ships spent time in the reserve fleet due to an economic depression
, but enough money was available by 1924 to have the dreadnoughts modernized in the United States. Both refits included a conversion from coal to fuel oil, a new fire-control system, and other minor improvements. In the 1930s they participated in training exercises and diplomatic cruises. Notable voyages included Morenos visit to Brazil with Argentine president Agustín Pedro Justo
aboard in 1933 and a later visit in 1934 to mark the centennial of Brazilian independence; Rivadavias and Morenos trip to Europe in 1937, where the two ships visited Brest
(France), Wilhelmshaven
, Bremen
, and Hamburg
(Germany) between them in addition to Morenos participation in the British Spithead Naval Review; and a 1939 visit by both battleships to Brazil with naval cadets embarked—destroyers were sent from Argentina to escort them home, as the Second World War had broken out during their stay.
During the war, both ships were mainly inactive due to Argentine neutrality. Rivadavia undertook a last diplomatic cruise to Trinidad, Venezuela, and Colombia in 1946, but both ships were immobile by 1948. Moreno was stricken from the naval register on 1 October 1956 and was brought to Japan in 1957 for scrapping
in a then-world-record 96-day tow. Rivadavia was stricken on 1 February 1957 and scrapped in Italy beginning in 1959. The money gained from selling the two dreadnoughts along with an older armored cruiser, , was used to buy an aircraft carrier
from the United Kingdom, Independencia
(ex-Warrior).
of 98 foot, a normal draft
of 27 foot, and displaced
27500 long tons (27,941.4 t) normally and 30100 long tons (30,583.1 t) at full load. The ships were staffed by 130 officers and about 1000 enlisted men.
For armament, the Rivadavia class was equipped with a main battery
of twelve 12-inch/50
caliber guns, a secondary battery of twelve 6-inch (155 mm)/50 and twelve 4-inch (102 mm)/50 QF
, and two 21-inch (533 mm) torpedo tube
s.
The 12"/50 was a Bethlehem development. It was most likely based on the weapon used in the United States' , the 12"/50 caliber Mark 7 gun. The twelve guns were mounted in six dual turrets. Four turrets were superfiring
fore and aft, while the other two were located en echelon in wing turrets. The latter weapons could, in theory, fire on a range on their respective sides of the hull and on the other, but in reality this was not possible, as the blast damage from the weapons would damage the ship. A more reasonable estimate would be on their sides. The 6-inch secondary armament was placed in casemate
s, with six on either side of the ship. For protection, they were provided with 6 inches of armor. The 4-inch weaponry, intended for use against marauding destroyer
s, was mounted unarmored in various places around the ship, including the main deck, superstructure, and far up near the bow. As originally built, there were sixteen 4-inch guns, but four of those were replaced with four 3-inch AA guns and four 3-pounders
during the 1924-1926 modernization. The torpedo tubes were located underneath the waterline and were loaded in a dedicated compartment.
Full ammunition loads were 1,440 rounds for the 12-inch guns (120 per gun), 3,600 rounds for the 6-inch (300), 5,600 rounds for the 4-inch (350), and 16 torpedoes manufactured by Whitehead
. To assist the main battery with targeting during a battle, the two ships were equipped with two Barr & Stroud rangefinder
s that were located above the conning tower
s.
Rivadavia and Moreno used Brown–Curtis
geared steam turbine
s, powered by 18 Babcock & Wilcox boiler
s and connected to three propeller
s. With a total output of about 40000 shp, the ships were designed to travel at a maximum speed of 22.5 knots (12.2 m/s) and may have been capable of slightly more. At speeds of 11 to 15 kn (6 to 8.2 ), their endurance ranged from 11000 nautical mile, respectively. Their fuel was a coal
–oil
mix and the ships carried 3900 long tons (3,962.6 t) of the former and 590 long tons (599.5 t) of the latter.
Typical of American-designed dreadnoughts at the time, the Rivadavia class included substantial armor protection. A 12 inches (304.8 mm) belt
was fitted amidships, covering 5 feet (1.5 m) above and 6 feet (1.8 m) below the designed waterline
, gradually decreasing towards the bow and stern to 5 inches (127 mm) and 4 inches (101.6 mm), respectively. The gun turrets received heavy armor, including 12 inches (304.8 mm) on the front, 9 inches (228.6 mm) on the sides, 9.5 inches (241.3 mm) on the back, and 4 inches (101.6 mm) on the top. Deck armor consisted of 0.5 inches (12.7 mm) medium steel
and 2 inches (50.8 mm) nickel steel.
Ship class
A ship class is a group of ships of a similar design. This is distinct from a ship-type, which might reflect a similarity of tonnage or intended use. For example, the is a nuclear aircraft carrier of the Nimitz class....
of battleship
Battleship
A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...
s (Spanish: acorazados) designed by the American Fore River Shipbuilding Company
Fore River Shipyard
The Fore River Shipyard of Quincy, Massachusetts, more formally known as the Fore River Ship and Engine Building Company, was a shipyard in the United States from 1883 until 1986. Located on the Weymouth Fore River, the yard began operations in 1883 in Braintree, Massachusetts before being moved...
for the Argentine Navy
Argentine Navy
The Navy of the Argentine Republic or Armada of the Argentine Republic is the navy of Argentina. It is one of the three branches of the Armed Forces of the Argentine Republic, together with the Army and the Air Force....
(Armada de la República Argentina). Named and after important figures in Argentine history, they were Argentina's counter to Brazil's two Minas Geraes-class battleships
Minas Geraes-class battleship
The Minas Geraes class, spelled Minas Gerais in some sources, consisted of two battleships built for the Brazilian Navy which began a South American dreadnought race. The ships were named Minas Geraes, after the Brazilian state, and São Paulo, honoring both the state and city...
.
In 1904, Brazil scrapped a previous naval building program in favor of an order that included two dreadnought
Dreadnought
The dreadnought was the predominant type of 20th-century battleship. The first of the kind, the Royal Navy's had such an impact when launched in 1906 that similar battleships built after her were referred to as "dreadnoughts", and earlier battleships became known as pre-dreadnoughts...
s, despite signs that such an action would spark a South American naval arms race
South American dreadnought race
A South American dreadnought race between Argentina, Brazil, and Chile was kindled in 1907 when the Brazilian government announced their intention to purchase three dreadnoughts—powerful battleships whose capabilities far outstripped older vessels in the world's navies—from the British company...
. To counter this acquisition by a major rival, Argentina began seeking bids for at least two dreadnoughts in 1908. Over the next two years, multiple shipbuilders from five countries vied for the contracts, complemented by efforts from their respective governments. Argentina was able to play this hyper-competitive environment to its own advantage by rejecting all of the initial proposals and calling for new ones that required the best aspects of each. They then repeated this process, despite complaints from shipbuilders that their trade secrets were being given away. The contracts were awarded to the lowest bidder, Fore River, in early 1910. This move shocked the European bidders, but could largely be explained by the American steel trust's ability to produce steel at a much lower cost than any other country.
During their construction, the Argentine battleships were frequently subject of rumors involving their sale to a foreign country, especially after the beginning of the First World War
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
. Under diplomatic pressure not to sell, Argentina kept the two ships. Throughout their careers, Rivadavia and Moreno were based in Puerto Belgrano
Puerto Belgrano
Base Naval Puerto Belgrano is the largest naval base of the Argentine Navy, situated next to Punta Alta, near Bahía Blanca, about south of Buenos Aires...
and served principally as training ships and diplomatic envoys. They were modernized in the United States in 1924 and 1925 and were inactive for much of the Second World War
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
due to Argentina's neutrality. Struck from the navy lists on 1 February 1957, Rivadavia was scrapped
Ship breaking
Ship breaking or ship demolition is a type of ship disposal involving the breaking up of ships for scrap recycling. Most ships have a lifespan of a few decades before there is so much wear that refitting and repair becomes uneconomical. Ship breaking allows materials from the ship, especially...
in Italy beginning in 1959. Moreno was struck on 1 October 1956 and was towed to Japan in 1957 for scrapping in what was then the world's longest tow (96 days).
Background
The raison d'être for the Rivadavia class can be traced back to Argentine–Chilean territorial disputes over the boundary of PatagoniaPatagonia
Patagonia is a region located in Argentina and Chile, integrating the southernmost section of the Andes mountains to the southwest towards the Pacific ocean and from the east of the cordillera to the valleys it follows south through Colorado River towards Carmen de Patagones in the Atlantic Ocean...
and control of the Beagle Channel
Beagle Channel
thumb|right|300px|Aereal view of Beagle Channel. The Chilean [[Navarino Island]] is seen in the top-right while the Argentine part of [[Isla Grande de Tierra del Fuego]] is seen at the bottom-left....
going back to the 1840s. It nearly led to war in 1878 and kindled a naval arms race from 1887 to 1902 which was only settled via British mediation. As part of the three pacts
Treaty of Arbitration between Chile and Argentina of 1902
The Cordillera of the Andes Boundary Case 1902 , was a British arbitration that established the present day boundaries between Argentina and Chile in Patagonia between the latitudes of 40° and 52° S as a interpretation of the Boundary treaty of 1881 between Chile and Argentina...
which ended the dispute, restrictions were placed on the navies of both countries. The British Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
bought two pre-dreadnought
Pre-dreadnought
Pre-dreadnought battleship is the general term for all of the types of sea-going battleships built between the mid-1890s and 1905. Pre-dreadnoughts replaced the ironclad warships of the 1870s and 1880s...
battleships that were being built for Chile, and Argentina sold its two Rivadavia-class
Kasuga class cruiser
The was a class of two armored cruisers of the Imperial Japanese Navy based on the developed by Italy at the end of the 19th century.-Background:...
armored cruiser
Armored cruiser
The armored cruiser was a type of warship of the late 19th and early 20th centuries. Like other types of cruiser, the armored cruiser was a long-range, independent warship, capable of defeating any ship apart from a battleship, and fast enough to outrun any battleships it encountered.The first...
s under construction in Italy to Japan. Meanwhile, beginning in the late 1880s, Brazil's navy fell into obsolescence after an 1889 revolution, which deposed Emperor
Politics of the Empire of Brazil
Politics of the Empire of Brazil took place in a framework of a quasi-federal parliamentary representative democratic monarchy, whereby the Emperor of Brazil was the head of state and nominally head of government although the President of the Council of Ministers was effectively the de facto head,...
Dom
Dom (title)
Dom is a title of respect prefixed to the given name. It derives from Latin Dominus.It is used in English for certain Benedictine and Carthusian monks, and for members of certain communities of Canons Regular. Examples include Benedictine monks of the English Benedictine Congregation...
Pedro II
Pedro II of Brazil
Dom Pedro II , nicknamed "the Magnanimous", was the second and last ruler of the Empire of Brazil, reigning for over 58 years. Born in Rio de Janeiro, he was the seventh child of Emperor Dom Pedro I of Brazil and Empress Dona Maria Leopoldina and thus a member of the Brazilian branch of...
, and a 1893 civil war
Revolta da Armada
Brazilian Naval Revolts, or the Revoltas da Armada , were armed mutinies promoted mainly by Admirals Custodio de Mello and Saldanha da Gama and their fleet of Brazilian Navy ships against unconstitucional attitudes of the then the central government in Rio de Janeiro.-First revolt:In November 1891,...
. By the turn of the 20th century it was lagging behind the Chilean and Argentine navies in quality and total tonnage, despite Brazil having nearly three times the population of Argentina and almost five times the population of Chile.
By 1904, however, Brazil began to seriously consider upgrading its navy to compete with Argentina and Chile. Soaring demand for coffee and rubber
Rubber boom
The rubber boom was an important part of the economic and social history of Brazil and Amazonian regions of neighboring countries, being related with the extraction and commercialization of rubber...
brought the Brazilian economy an influx of revenue, which paid for a $31.25 million (in 20 dollars, $) naval repair scheme, a substantial amount for the time period. The bill authorized 28 ships, including three battleships and three armored cruisers. It was not possible to lay down the battleships until 1906, the same year the trend-setting was constructed. This ship prompted the Brazilians to cancel their battleship plans in favor of two Minas Geraes-class
Minas Geraes-class battleship
The Minas Geraes class, spelled Minas Gerais in some sources, consisted of two battleships built for the Brazilian Navy which began a South American dreadnought race. The ships were named Minas Geraes, after the Brazilian state, and São Paulo, honoring both the state and city...
dreadnought
Dreadnought
The dreadnought was the predominant type of 20th-century battleship. The first of the kind, the Royal Navy's had such an impact when launched in 1906 that similar battleships built after her were referred to as "dreadnoughts", and earlier battleships became known as pre-dreadnoughts...
s. The ordering of these powerful ships—designed to carry the heaviest armament in the world at the time—shocked Argentina and Chile. Historian Robert Scheina comments that the dreadnoughts alone "outclassed the entire [elderly] Argentinian fleet."
Debates raged in Argentina over the wisdom of acquiring dreadnoughts to counter Brazil's. The National Autonomist Party
National Autonomist Party
The National Autonomist Party was an Argentine political party during the 1874-1916 period. Created on March 15, 1874 by the union of the Autonomist Party of Adolfo Alsina and the National Party of Nicolás Avellaneda...
cabinet was in favor, despite a probable cost of over $9.74 million (in 20 dollars, $), but a specific plan for two 14000 long tons (14,225 t) battleships and ten destroyers was not popular with the public. Alarmed, the American ambassador to Brazil sent a cablegram
Cablegram
A cablegram, sometimes shortened to just cable, was a telegram, a text possibly encrypted, which was transmitted through the means of an electrical cable, underwater or aerial....
to his Department of State
United States Department of State
The United States Department of State , is the United States federal executive department responsible for international relations of the United States, equivalent to the foreign ministries of other countries...
, warning them of the destabilizing effects that would occur if the situation devolved into a full naval arms race.
Despite American entreaties to preclude the naval arms race, Brazil continued development on the ships. This, combined with renewed border disputes, particularly in the River Plate
Río de la Plata
The Río de la Plata —sometimes rendered River Plate in British English and the Commonwealth, and occasionally rendered [La] Plata River in other English-speaking countries—is the river and estuary formed by the confluence of the Uruguay River and the Paraná River on the border between Argentina and...
(Río de la Plata, literally "Silver River") area, spurred Argentina to move forward with plans for their own battleships. Inflamed by newspaper editors, the public was now fully supportive of a naval building program. While an early plan called for $35 million to be invested—$7 million from foreign loans—a $55 million (in 20 dollars, these numbers are (respectively) $, $, $) plan was adopted in August 1908. Hoping to end the arms race, Argentina made an offer to purchase one of the two Brazilian ships, but the refusal prompted the dispatch of an Argentine naval commission to Europe to acquire dreadnoughts.
Bidding
Fifteen shipyards from the United States, Great Britain, Germany, France, and Italy began bidding on the battleships. Diplomatic pressure to give the contracts was brought to bear from all these countries, especially the first three. Even with this assistance, industry leaders in the United States believed that they had no chance in the bidding without active cooperation from their government, as Europe was the traditional arms supplier to Argentina (and to all of South America). Even when this was given, including the removal of import tariffs on hides
Hides
A hide is an animal skin treated for human use. Hides include leather from cattle and other livestock animals, alligator skins, snake skins for shoes and fashion accessories and furs from wild cats, mink and bears. In some areas, leather is produced on a domestic or small industrial scale, but most...
from Argentina, promises for additional concessions if American shipbuilders were selected, and an offer to include the most technologically advanced fire-control system
Fire-control system
A fire-control system is a number of components working together, usually a gun data computer, a director, and radar, which is designed to assist a weapon system in hitting its target. It performs the same task as a human gunner firing a weapon, but attempts to do so faster and more...
and torpedo tube
Torpedo tube
A torpedo tube is a device for launching torpedoes. There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units installed aboard surface vessels...
s available on the Argentine battleships, the United States was widely viewed as a non-contender. Historian Seward W. Livermore remarked:
The president of the Newport News Shipbuilding and Drydock Company believed that the United States would not receive contracts due to what he saw as a large amount of European meddling in Argentina:
The United States, however, found an ally in Buenos Aires' main daily newspaper, La Prensa
La Prensa (Buenos Aires)
La Prensa is an Argentine daily newspaper.Based in Buenos Aires, it was founded on 18 October 1869 by José C. Paz. La Prensa ranked among the most widely circulated dailies in Argentina in subsequent decades, earning a reputation for conservatism and support for British interests in Argentina...
. The owner, editor, and naval editor were all in favor of acquiring American-designed dreadnoughts. In addition, the paper found evidence of British wrongdoing in a related naval contract. Under public pressure, the naval commission was forced to reconsider its original list, which had placed Italy first and Britain second. It now featured the United States first, Britain second, and Italy last.
In a surprise move, the Argentine naval commission then threw out all of the opening tenders and called for another round of bidding; they simultaneously updated the specifications to include what were judged to be the best aspects of all the plans. The competitors were given three weeks to come up with new designs and cost estimates. After diplomatic protests, this was modified slightly; the original bids were kept, but alterations to attempt to conform to the new desired characteristics were allowed.
The commission found that the Newport News Shipbuilding and Drydock Company bid was lowest on one battleship, and the Fore River Shipbuilding Company
Fore River Shipyard
The Fore River Shipyard of Quincy, Massachusetts, more formally known as the Fore River Ship and Engine Building Company, was a shipyard in the United States from 1883 until 1986. Located on the Weymouth Fore River, the yard began operations in 1883 in Braintree, Massachusetts before being moved...
was lowest on the other. Despite a British attempt to allow the Armstrong Whitworth
Armstrong Whitworth
Sir W G Armstrong Whitworth & Co Ltd was a major British manufacturing company of the early years of the 20th century. Headquartered in Elswick, Newcastle upon Tyne, Armstrong Whitworth engaged in the construction of armaments, ships, locomotives, automobiles, and aircraft.-History:In 1847,...
-Vickers
Vickers Limited
Vickers Limited was a famous British engineering conglomerate that merged into Vickers-Armstrongs in 1927.-Early history:Vickers was formed in Sheffield as a steel foundry by the miller Edward Vickers and his father-in-law George Naylor in 1828. Naylor was a partner in the foundry Naylor &...
team to lower their price by $570,000, prompt American diplomacy granting various assurances regarding recent events between the United States and Brazil, the upcoming 1910 Pan-American Conference
Pan-American Conference
The Conferences of American States, commonly referred to as the Pan-American Conferences, were meetings of the Pan-American Union, an international organization for cooperation on trade and other issues. They were first introduced by James G. Blaine of Maine in order to establish closer ties...
, and a guarantee of American participation in the Argentine centennial celebrations secured the battleship contracts for Fore River on 21 January 1910. The maximum price Fore River tendered, $10.7 million (in 20 dollars, $), underbid the British by more than $973,000. Italy's tender was just $48,600 more, but their ship's displacement
Displacement (ship)
A ship's displacement is its weight at any given time, generally expressed in metric tons or long tons. The term is often used to mean the ship's weight when it is loaded to its maximum capacity. A number of synonymous terms exist for this maximum weight, such as loaded displacement, full load...
was 2000 long tons (2,032 t) smaller, the belt armor
Belt armor
Belt armor is a layer of heavy metal armor plated on to or within outer hulls of warships, typically on battleships, battlecruisers and cruisers, and on aircraft carriers converted from those types of ships....
was 2 inches (50.8 mm) thinner, and the top speed was slightly slower.
Rivadavia was built by Fore River at its shipyard in Massachusetts; as called for in the final contract, Moreno was subcontracted
Subcontractor
A subcontractor is an individual or in many cases a business that signs a contract to perform part or all of the obligations of another's contract....
out to the New York Shipbuilding Corporation
New York Shipbuilding
The New York Shipbuilding Corporation was founded in 1899 and opened its first shipyard in 1900. Located in Camden, New Jersey on the east shore of the Delaware River, New York Ship built more than 500 vessels for the U.S...
of New Jersey. The steel for the ships was largely supplied by the Bethlehem Steel Company of Pennsylvania, which, due to their ability to produce steel at a lower price than other nations, was an integral cost-saving measure. The Secretary of the Argentine Naval Commission, the body which chose the final design, said the reason the American tender was lower than that of the English was that "steel for construction work and armor-plating is a great deal cheaper in the United States than in England. Wages are higher there, but the contractors ... are able to obtain it more cheaply owing to the manipulations of the Steel Trust."
A third dreadnought, provided for in the contract, was strongly supported by Argentina and by U.S. diplomats during 1910, while the Minas Geraes class was still under construction. La Prensa and one of its rivals, La Argentina
La Nación
La Nación is an Argentine daily newspaper. The country's leading conservative paper, the centrist Clarín is its main competitor. It is the only newspaper in Argentina still published in broadsheet format.-Overview:...
, heavily advocated a third ship; the latter even started a petition to raise money for a new battleship. An American diplomat wrote back to the United States that "this newspaper rivalry promises the early conclusion of a movement which means a third battleship whether by public subscription or by Government funds." However, Brazil's 21–26 November Revolta da Chibata
Revolt of the Whip
The Revolt of the LashOther names for the mutiny include the "Revolt of the Whip" or the "Revolt against the Lash." , was a 1910 naval incident that occurred in Rio de Janeiro, Brazil...
("Revolt of the Whip"), in which the three most powerful ships in the fleet (the battleships , , and the cruiser ) along with an older coast defense ship (Deodoro) violently rebelled, crushed the previous sentiment for a new battleship. About two years later in October 1912, a third dreadnought was authorized by Argentina in case Brazil's Rio de Janeiro
HMS Agincourt (1913)
HMS Agincourt was a dreadnought built in the early 1910s. The ship was originally ordered by Brazil, but the collapse of the rubber boom plus a lessening of the rivalry with Argentina led to her resale while still under construction to the Ottoman Empire who renamed her as Sultan Osman I...
was completed and delivered. The ship was never named or built, as Rio de Janeiro was sold to the Ottoman Empire
Ottoman Empire
The Ottoman EmpireIt was usually referred to as the "Ottoman Empire", the "Turkish Empire", the "Ottoman Caliphate" or more commonly "Turkey" by its contemporaries...
due to monetary issues, and a later planned Brazilian ship was canceled due to the beginning of the First World War
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
.
International reaction
The choice of Fore River came as a complete surprise to the European bidders. Britain's reaction in particular was scathing: John H. Biles, a naval architect, decried the bidding process as "unethical" and remarked:Various British newspapers also cried foul. The Evening Standard
Evening Standard
The Evening Standard, now styled the London Evening Standard, is a free local daily newspaper, published Monday–Friday in tabloid format in London. It is the dominant regional evening paper for London and the surrounding area, with coverage of national and international news and City of London...
believed that as "Argentina's greatest creditor and greatest client", Britain ought to have been awarded the two ships. The Times
The Times
The Times is a British daily national newspaper, first published in London in 1785 under the title The Daily Universal Register . The Times and its sister paper The Sunday Times are published by Times Newspapers Limited, a subsidiary since 1981 of News International...
took a different track, accusing American shipbuilders of slashing prices to an obscene degree, and accusing the government of exerting undue diplomatic pressure to obtain the contracts.
New Zealand's Evening Post
The Evening Post (New Zealand)
The Evening Post was a daily newspaper based in Wellington, New Zealand. It was founded in 1865 by Henry Blundell , an Irish immigrant to New Zealand. It continued under Blundell family control until the 1960s, when it was purchased by Independent Newspapers Ltd.In 2002 it merged with The...
noted that the United States had previously built major warships for other countries, including Russia's and Britain's ally Japan, and commented, "The severity of the blow to England rests in ... the amount of English capital in [Argentina]", possibly echoing the Evening Standards argument. They referred to a "startling" fact printed by the Daily Mail
Daily Mail
The Daily Mail is a British daily middle-market tabloid newspaper owned by the Daily Mail and General Trust. First published in 1896 by Lord Northcliffe, it is the United Kingdom's second biggest-selling daily newspaper after The Sun. Its sister paper The Mail on Sunday was launched in 1982...
: the steel used for the armor of the American design was obtained for a much lower price. With Bethlehem's ability to produce it at £8 less per ton than British foundries, a cost savings of more than 10% in steel over the British ship could be realized.
Germany asserted that the United States was given the opportunity to view the other nations' tenders and lower their price accordingly. Germany also alleged that the United States had secured the deal by pledging to come to Argentina's defense should they become embroiled in a military conflict.
The New York Times noted that with Argentina's and Brazil's dreadnought orders, countries in North and South America were building the five biggest capital ships in the world (Brazil's Rio de Janeiro, Argentina's Rivadavia and Moreno, and the United States' and ) in addition to seven of the ten largest (including the United States' and ). Shortly after Rivadavia had completed her trials, the U.S. Navy's Board of Inspection and Survey
Board of Inspection and Survey
The Board of Inspection and Survey is a U.S. Navy organization whose purpose is to inspect and assess material condition of Naval vessels.The Board is currently headquartered at Naval Amphibious Base Little Creek, Virginia.- INSURV teams :...
remarked that she "handle[d] remarkably well ... with comparatively minor modifications the vessel would practically meet the requirements of our own vessels." The Board of Inspection was less pleased with the wing turrets, stating that "while theoretically the Rivadavia has an ahead and astern fire of six guns, this is not so in reality, as it is almost certain that the blast from the waist turrets would dish in the smokepipes and damage the uptakes."
Possible sale
After Brazil sold Rio de Janeiro to the Ottoman Empire, Argentina began to actively seek a buyer for their two ships so the profits could be invested in education. In the tension that preceded the First World War, there were many suitors. The United States, however, abhorred the idea of the their latest technological advances falling into the hands of a possible future combat opponent. While the contract allowed the United States Navy an option to acquire the ships if a deal was reached with a third nation, the navy did not want the ships; with the rapid advances in dreadnought technology, such as the "all or nothing" armor arrangement, even new ships like Rivadavia and Moreno were seen as outmoded.Three bills directing that the battleships be sold were introduced into the Argentine National Congress
Argentine National Congress
The Congress of the Argentine Nation is the legislative branch of the government of Argentina. Its composition is bicameral, constituted by a 72-seat Senate and a 257-seat Chamber of Deputies....
in the summer of 1914, but all were defeated. Still, soon after the beginning of the First World War, the German ambassador to Argentina alleged to the U.S. State Department that Britain's Royal Navy was going to take over the ships as soon as the ships reached the River Plate, and the British put diplomatic pressure on the United States to try to ensure the ships were not sold to any other country (as this new country could in turn sell them to Germany). Italy, the Ottomans, and Greece were all reportedly interested in buying both ships, the latter as a counter to the Ottoman purchase of Rio de Janeiro. The United States, worried that its neutrality would not be respected and its technology would be released for study to a foreign country, diplomatically pressured Argentina to keep the ships, which it eventually did.
Design influences
The Rivadavia design was very similar to a 1906 proposal from Fore River for an American dreadnought class. This ship would have mounted a main batteryMain battery
Generally used only in the terms of naval warfare, the main battery is the primary weapon around which a ship was designed. "Battery" is in itself a common term in the military science of artillery. For example, the United States Navy battleship USS Washington had a main battery of nine guns...
of fourteen 12 inches (304.8 mm) guns in dual turrets (two superfiring
Superfire
The idea of superfire is to locate two turrets in a row, one behind the other, but with the second turret located above the one in front so that the second turret could fire over the first...
fore, two wing, and three non-superfiring aft), a secondary battery of twenty 4-inch (102 mm) guns and four torpedo tube
Torpedo tube
A torpedo tube is a device for launching torpedoes. There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units installed aboard surface vessels...
s on a hull of 22000 long tons (22,353 t) that would be capable of 21 kn (25.6 mph; 41.2 km/h). Foreign practices also bore a large influence on the design; most were acquired through the unique design process of rejecting multiple bids and calling for the best aspects of each. For example, the superfiring arrangement of the main battery was an American innovation, while the wing turrets were similar to British designs of the time. The secondary battery of 6-inch (152 mm) guns and the three-shaft system were influenced by German design practices, while the engine and boiler layout was reminiscent of the Italian battleship .
Service histories
was named after Bernardino RivadaviaBernardino Rivadavia
Bernardino de la Trinidad Gónzalez Rivadavia y Rivadavia was the first president of Argentina, from February 8, 1826 to July 7, 1827 . He was a politician of the United Provinces of Río de la Plata, Argentina today...
, the first president of Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
, and was built by Fore River Shipyard
Fore River Shipyard
The Fore River Shipyard of Quincy, Massachusetts, more formally known as the Fore River Ship and Engine Building Company, was a shipyard in the United States from 1883 until 1986. Located on the Weymouth Fore River, the yard began operations in 1883 in Braintree, Massachusetts before being moved...
. She was laid down on 25 May 1910, launched
Ship naming and launching
The ceremonies involved in naming and launching naval ships are based in traditions thousands of years old.-Methods of launch:There are three principal methods of conveying a new ship from building site to water, only two of which are called "launching." The oldest, most familiar, and most widely...
on 26 August 1911, and completed in December 1914. was named after Mariano Moreno
Mariano Moreno
Mariano Moreno was an Argentine lawyer, journalist, and politician. He played a decisive role in the Primera Junta, the first national government of Argentina, created after the May Revolution....
, a member of the first Argentine government in May 1810, and was built by New York Shipbuilding Corporation. She was laid down on 10 July 1910, launched on 23 September 1911, and completed in February 1915. Both ships had engine trouble soon after completion: Rivadavias completion was delayed due to a damaged turbine, while Moreno had an entire turbine fail while on her trials.
The ships finally arrived in Argentina in February and May 1915, respectively. In the early 1920s, both ships spent time in the reserve fleet due to an economic depression
Depression (economics)
In economics, a depression is a sustained, long-term downturn in economic activity in one or more economies. It is a more severe downturn than a recession, which is seen by some economists as part of the modern business cycle....
, but enough money was available by 1924 to have the dreadnoughts modernized in the United States. Both refits included a conversion from coal to fuel oil, a new fire-control system, and other minor improvements. In the 1930s they participated in training exercises and diplomatic cruises. Notable voyages included Morenos visit to Brazil with Argentine president Agustín Pedro Justo
Agustín Pedro Justo
General Agustín Pedro Justo Rolón was President of Argentina from February 20, 1932, to February 20, 1938...
aboard in 1933 and a later visit in 1934 to mark the centennial of Brazilian independence; Rivadavias and Morenos trip to Europe in 1937, where the two ships visited Brest
Brest, France
Brest is a city in the Finistère department in Brittany in northwestern France. Located in a sheltered position not far from the western tip of the Breton peninsula, and the western extremity of metropolitan France, Brest is an important harbour and the second French military port after Toulon...
(France), Wilhelmshaven
Wilhelmshaven
Wilhelmshaven is a coastal town in Lower Saxony, Germany. It is situated on the western side of the Jade Bight, a bay of the North Sea.-History:...
, Bremen
Bremen
The City Municipality of Bremen is a Hanseatic city in northwestern Germany. A commercial and industrial city with a major port on the river Weser, Bremen is part of the Bremen-Oldenburg metropolitan area . Bremen is the second most populous city in North Germany and tenth in Germany.Bremen is...
, and Hamburg
Hamburg
-History:The first historic name for the city was, according to Claudius Ptolemy's reports, Treva.But the city takes its modern name, Hamburg, from the first permanent building on the site, a castle whose construction was ordered by the Emperor Charlemagne in AD 808...
(Germany) between them in addition to Morenos participation in the British Spithead Naval Review; and a 1939 visit by both battleships to Brazil with naval cadets embarked—destroyers were sent from Argentina to escort them home, as the Second World War had broken out during their stay.
During the war, both ships were mainly inactive due to Argentine neutrality. Rivadavia undertook a last diplomatic cruise to Trinidad, Venezuela, and Colombia in 1946, but both ships were immobile by 1948. Moreno was stricken from the naval register on 1 October 1956 and was brought to Japan in 1957 for scrapping
Ship breaking
Ship breaking or ship demolition is a type of ship disposal involving the breaking up of ships for scrap recycling. Most ships have a lifespan of a few decades before there is so much wear that refitting and repair becomes uneconomical. Ship breaking allows materials from the ship, especially...
in a then-world-record 96-day tow. Rivadavia was stricken on 1 February 1957 and scrapped in Italy beginning in 1959. The money gained from selling the two dreadnoughts along with an older armored cruiser, , was used to buy an aircraft carrier
Aircraft carrier
An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...
from the United Kingdom, Independencia
HMS Warrior (R31)
HMS Warrior was a Colossus-class light aircraft carrier which served in the Royal Canadian Navy from 1946 to 1948 , the Royal Navy from 1948 to 1958, and the Argentine Navy from 1959 to 1969 .- History :Built by Harland and Wolff in Belfast, she was originally to be called HMS Brave; the Royal...
(ex-Warrior).
Specifications
The two ships of the Rivadavia class were 594 in 9 in (181.28 m) overall and 585 feet (178.3 m) between perpendiculars. They had a beamBeam (nautical)
The beam of a ship is its width at the widest point. Generally speaking, the wider the beam of a ship , the more initial stability it has, at expense of reserve stability in the event of a capsize, where more energy is required to right the vessel from its inverted position...
of 98 foot, a normal draft
Draft (hull)
The draft of a ship's hull is the vertical distance between the waterline and the bottom of the hull , with the thickness of the hull included; in the case of not being included the draft outline would be obtained...
of 27 foot, and displaced
Displacement (ship)
A ship's displacement is its weight at any given time, generally expressed in metric tons or long tons. The term is often used to mean the ship's weight when it is loaded to its maximum capacity. A number of synonymous terms exist for this maximum weight, such as loaded displacement, full load...
27500 long tons (27,941.4 t) normally and 30100 long tons (30,583.1 t) at full load. The ships were staffed by 130 officers and about 1000 enlisted men.
For armament, the Rivadavia class was equipped with a main battery
Main battery
Generally used only in the terms of naval warfare, the main battery is the primary weapon around which a ship was designed. "Battery" is in itself a common term in the military science of artillery. For example, the United States Navy battleship USS Washington had a main battery of nine guns...
of twelve 12-inch/50
12"/50 caliber gun (Argentina)
The 12"/50 caliber Bethlehem gun was a US naval gun designed in 1910 as the main armament for the Argentine Navy’s dreadnought battleships of the Rivadavia class.- Design :...
caliber guns, a secondary battery of twelve 6-inch (155 mm)/50 and twelve 4-inch (102 mm)/50 QF
Quick-firing gun
A quick-firing gun is an artillery piece, typically a gun or howitzer, which has several characteristics which taken together mean the weapon can fire at a fast rate...
, and two 21-inch (533 mm) torpedo tube
Torpedo tube
A torpedo tube is a device for launching torpedoes. There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units installed aboard surface vessels...
s.
The 12"/50 was a Bethlehem development. It was most likely based on the weapon used in the United States' , the 12"/50 caliber Mark 7 gun. The twelve guns were mounted in six dual turrets. Four turrets were superfiring
Superfire
The idea of superfire is to locate two turrets in a row, one behind the other, but with the second turret located above the one in front so that the second turret could fire over the first...
fore and aft, while the other two were located en echelon in wing turrets. The latter weapons could, in theory, fire on a range on their respective sides of the hull and on the other, but in reality this was not possible, as the blast damage from the weapons would damage the ship. A more reasonable estimate would be on their sides. The 6-inch secondary armament was placed in casemate
Casemate
A casemate, sometimes rendered casement, is a fortified gun emplacement or armored structure from which guns are fired. originally a vaulted chamber in a fortress.-Origin of the term:...
s, with six on either side of the ship. For protection, they were provided with 6 inches of armor. The 4-inch weaponry, intended for use against marauding destroyer
Destroyer
In naval terminology, a destroyer is a fast and maneuverable yet long-endurance warship intended to escort larger vessels in a fleet, convoy or battle group and defend them against smaller, powerful, short-range attackers. Destroyers, originally called torpedo-boat destroyers in 1892, evolved from...
s, was mounted unarmored in various places around the ship, including the main deck, superstructure, and far up near the bow. As originally built, there were sixteen 4-inch guns, but four of those were replaced with four 3-inch AA guns and four 3-pounders
Ordnance QF 3 pounder Vickers
The Ordnance QF 3 pounder Vickers was a British artillery piece first tested in Britain in 1910. It was used on Royal Navy warships. It was more powerful than and unrelated to the older QF 3 pounder Hotchkiss, with a propellant charge approximately twice as large, but it initially fired the same...
during the 1924-1926 modernization. The torpedo tubes were located underneath the waterline and were loaded in a dedicated compartment.
Full ammunition loads were 1,440 rounds for the 12-inch guns (120 per gun), 3,600 rounds for the 6-inch (300), 5,600 rounds for the 4-inch (350), and 16 torpedoes manufactured by Whitehead
Robert Whitehead
Robert Whitehead was an English engineer. He developed the first effective self-propelled naval torpedo. His company, located in the Austrian naval centre in Fiume, was the world leader in torpedo development and production up to the First World War.- Early life:He was born the son of a...
. To assist the main battery with targeting during a battle, the two ships were equipped with two Barr & Stroud rangefinder
Rangefinder
A rangefinder is a device that measures distance from the observer to a target, for the purposes of surveying, determining focus in photography, or accurately aiming a weapon. Some devices use active methods to measure ; others measure distance using trigonometry...
s that were located above the conning tower
Conning tower
A conning tower is a raised platform on a ship or submarine, often armored, from which an officer can con the vessel; i.e., give directions to the helmsman. It is usually located as high on the ship as practical, to give the conning team good visibility....
s.
Rivadavia and Moreno used Brown–Curtis
John Brown & Company
John Brown and Company of Clydebank was a pre-eminent Scottish marine engineering and shipbuilding firm, responsible for building many notable and world-famous ships, such as the , the , the , the , the , and the...
geared steam turbine
Steam turbine
A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into rotary motion. Its modern manifestation was invented by Sir Charles Parsons in 1884....
s, powered by 18 Babcock & Wilcox boiler
Boiler
A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...
s and connected to three propeller
Propeller
A propeller is a type of fan that transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of the airfoil-shaped blade, and a fluid is accelerated behind the blade. Propeller dynamics can be modeled by both Bernoulli's...
s. With a total output of about 40000 shp, the ships were designed to travel at a maximum speed of 22.5 knots (12.2 m/s) and may have been capable of slightly more. At speeds of 11 to 15 kn (6 to 8.2 ), their endurance ranged from 11000 nautical mile, respectively. Their fuel was a coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
–oil
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....
mix and the ships carried 3900 long tons (3,962.6 t) of the former and 590 long tons (599.5 t) of the latter.
Typical of American-designed dreadnoughts at the time, the Rivadavia class included substantial armor protection. A 12 inches (304.8 mm) belt
Belt armor
Belt armor is a layer of heavy metal armor plated on to or within outer hulls of warships, typically on battleships, battlecruisers and cruisers, and on aircraft carriers converted from those types of ships....
was fitted amidships, covering 5 feet (1.5 m) above and 6 feet (1.8 m) below the designed waterline
Waterline
The term "waterline" generally refers to the line where the hull of a ship meets the water surface. It is also the name of a special marking, also known as the national Load Line or Plimsoll Line, to be positioned amidships, that indicates the draft of the ship and the legal limit to which a ship...
, gradually decreasing towards the bow and stern to 5 inches (127 mm) and 4 inches (101.6 mm), respectively. The gun turrets received heavy armor, including 12 inches (304.8 mm) on the front, 9 inches (228.6 mm) on the sides, 9.5 inches (241.3 mm) on the back, and 4 inches (101.6 mm) on the top. Deck armor consisted of 0.5 inches (12.7 mm) medium steel
Maraging steel
Maraging steels are steels which are known for possessing superior strength and toughness without losing malleability, although they cannot hold a good cutting edge. Aging refers to the extended heat-treatment process...
and 2 inches (50.8 mm) nickel steel.