Reliable machinery gave Gorgon near-cruising speed endurance

Gorgon's machinery illustrates why an older propulsion technology could still be the rational choice for a specialized warship. Four Yarrow boilers fed two vertical triple-expansion engines producing about 4,000 indicated horsepower. The class could make roughly 12 knots and steam about 2,700 nautical miles at 11 knots, so its economical cruising speed sat close to its maximum. Reliability, familiar maintenance, and controlled cost mattered more than turbine prestige. Those priorities suited a ship expected to move between coastal positions and then fight from a relatively fixed station. A complement of about 305 also kept the ship substantial without approaching battleship manpower demands.