Scylla and Charybdis carried 4.5-inch guns in UD Mark III upper-deck mountings. Their armament brought them closer to a specialist anti-aircraft role than the other Didos. The mounting was heavy enough that experience aboard the cruisers helped explain the Battle-class decision to use BD mountings. A cruiser could accommodate equipment that remained unsuitable for a destroyer. The upper-deck project eventually reached the Daring class as the UD Mark 6, after intermediate designs failed to reach comparable sea service.
Notable Point · 58:23-1:00:58
Scylla and Charybdis tested the 4.5-inch upper-deck mounting
The two cruisers' 4.5-inch batteries tested a mounting whose weight and operating problems delayed its adoption by destroyers.