"Hero" displaced at standard load and at deep load. The ship had an overall length of , a beam of and a draught of . She was powered by Parsons geared steam turbines, driving two shafts, which developed a total of and gave a maximum speed of . Steam for the turbines was provided by three Admiralty 3-drum water-tube boilers. "Hero" carried a maximum of of fuel oil that gave her a range of at . The ship's complement was 137 officers and men in peacetime, but this increased to 146 in wartime. In Canadian service, the crew numbered 10 officers and 171 men.