For the first time in over thirty years an Amazonian destroyer class was not armed with single 4" guns. 1931-32 and the advent of dual purpose weapons came to destroyers in the shape of twin 4" mountings. This required new directors to control these weapons. Quad sets of torpedo tubes, quad 2 pounder AA guns and 20mm cannons finished the AA/Surface armament. For subsurface battles the Otrera class were the first to be fitted with new Asdic detection system, while the depth charges aft would hopefully destroy anything detected. Not being under any Treaty obligations, these ships were built at Destroyer Leader size as befitted the first Queen of the Amazons.
One Otrera would lead four Valasca class destroyers as a Destroyer Squadron, with a senior Commander or Captain in command from the Otrera. This made a very potent force. Very rarely did they get the opportunity to escape the clutches of the Fleet. 1940 and the Otrera and its Squadron were based at Scapa Flow when they were dispatched to Norway to try and intercept the Germanic States invaders of Norway. Able to make 30 knots the five ships came across and intercepted the Kristiandsand Group of a light cruiser two minesweepers and a pair of R Boats. It was almost no contest as the fast firing 4" overwhelmed the German force. While not able to pierce the cruisers armour, the 4" swept the decks of everything else. Two torpedo hits on the cruiser completed the rout of the German force. The Otrera took half a dozen 5.9" hits and required some dock time for repairs.
By 1943 the ships remaining of the class (4) had all of the refits that they were going to get. 40mm and predictors replaced the 2 pounder and 20mm. The masts had to be cut down to fit the Radar units as topweight was beginning to be a problem. The Sisterhood did not want to lose any of the banks of torpedoes on these ships, as these were the big teeth against larger ships. As had been shown against the Karlsruhe.
