These ships were designed to be 'Fleet' destroyers from the start. Big good looking destroyers, the extra fifth 5" gun, with all of them being dual purpose, 85 degree mountings, made the world of difference to the ships capabilities. The first four were built to be the 'Vanguard' of the fleet. These ships were fitted with anti-mine sweeps that would clear a path through any mine infested waters at fleet speed. Numbers 5-24 had the normal depth charge racks and throwers. These ships were big enough to provide their own leaders and did so. The next Destroyer Leader class built was for the previous destroyer classes.
The evolution of the ships followed the pretty much standard route with more and more electronics being added from 1939 onwards. More depth charges, then Hedgehog were added and finally something had to give. The aft set of quadruple torpedo tubes being removed in 1942. The biggest change brought by the electronics was the accuracy of the guns. Both 40mm and 5" had targeting radar from 1941 and with upgrades and new equipment the guns accuracy got only better. This also applied to the search radar for the air and search functions. Being the outriders to the Fleet they needed to be able to pick up incoming enemy action as soon as possible, again these sets of radar improved as better equipment was discovered and put aboard the ships.
