Third class of dreadnought type ships ever to be built, the ships caused quite a stir when completed in 1910 with their 4 superfiring turrets and the fifth turret in what was essentially a 'Q' turret position. They were of a size with the British dreadnoughts but their armour at 9" was less than the belts on the British ships. The ships took no part in the First World War and were given only small refurbishment to what were essentially 2nd class battleships or training ships.
These two ships were the oldest battleships in service with the Navy. It was felt that spending money on them would be wasted and would be better spent on new construction. The speed of the ships was about 20 knots which it was decided would do as the ships were not big enough to spend too much money on trying to improve. After 1930 the ships were mainly used for training purposes as new construction took over their main roles. 2 pounder AA guns were fitted in the 1920's and that was the extent of additions. These ships were not expected to be in harms way. Despite this hope the Sao Paulo was indeed in harms way when it was with the Amazonas escorting ships from Sierra Leone to Rio de Janeiro. The Sao Paulo was there to guard against raiders attacking the convoy. A U-boat had fired a spread of torpedoes at the Sao Paulo and Amazonas. One hit the Sao Paulo and two the Amazonas. Both ships sank. The Sao Paulo had never had decent underwater protection. One hit was enough to open two large compartments to the sea which then caused bulkheads to fracture and more water to enter the hull, capsizing the Sao Paulo. Being January in the South Atlantic the water was warm and lots of crew were pulled from the water from both ships.
