The machinery cost of sustained Tribal-class speed

The Tribals' machinery problems grew from the relationship between a light installation and unusually hard use. Similar machinery in the Battle class weighed about 25 percent more because it included the cushioning and shock mountings needed to control vibration. Tribals assigned to battlecruisers often had to run one or two knots faster than destroyers screening slower battleships, which magnified wear and maintenance trouble. The analogy compares this with Hawker Hurricanes and Supermarine Spitfires operated continually at full speed in Soviet service. An acceptable limitation under the assumed operating pattern became a chronic problem when the machinery was driven harder.