 Following the war-time trend to install director firing in ever-smaller vessels as resources permitted, "Lightfoot" was selected to serve as a test-bed for the Royal Navy's new training-only director firing system for flotilla leaders and destroyers in March 1917.By August, results obtained were favourable enough that it was decided to equip fully 203 other leaders and destroyers of "L" class and later.Two were ordered under the 1913–14 Programme.