Project 7U's unit machinery arrangement was intended to improve survivability following the example of a British destroyer damaged by a mine. The arrangement had already been used on other ships. Reported range still varied from about 2,700 nautical miles to just under 1,400 nautical miles at 19 knots, with altered fuel storage again blamed. The weapons, barrel erosion and equipment difficulties remained broadly similar to those of Gnevny. Against a target of 38 knots, examples are credited with results from 36.8 to 40 knots. The ship credited with 36.8 knots was also one of the short-ranged examples. The class was nevertheless useful in service.
Chapter · 43:50-45:42
Project 7U: unit machinery and persistent variation
Unit machinery sought better survivability, while inconsistent range, speed and gun wear continued to complicate the revised destroyers.