La Argentina's 165-metre length and 17.22-metre beam made her longer and broader than the Arethusa design while leaving draft broadly similar. Four Yarrow boilers and Parsons geared turbines drove four shafts with 54,000 horsepower for 30 knots, against the Arethusas' 64,000 horsepower and roughly 32 knots. The decisive difference was an advertised range of 12,000 nautical miles at 12 knots, compared with about 5,300 nautical miles at 13 knots for the British class. The modest sacrifice in speed and power suited long-range patrol, presence missions, distant commitments, and convoy work.
Chapter · 11:24-13:38
Why range mattered more than a small speed advantage
A comparison with the Arethusa class shows how La Argentina traded some speed for a dramatically longer patrol radius.