My father-in-law was on HMS Liverpool:
On 25 May, Liverpool began escorting PQ 16, a convoy of 35 merchant vessels bound for Murmansk, the largest convoy yet undertaken in support of the Soviet Union. PQ 16 had considerable protection, including the light and heavy cruisers Nigeria, Kent, and Norfolk, and numerous destroyers and submarines, with distant cover provided by the Home Fleet.[54] Inevitably, the convoy came under attack, beginning with a sortie on the 25th that damaged the freighter SS Carlton. Sustained attacks from U-boats and at least 242 German aircraft yielded a total of seven vessels sunk on the 26th and 27th.
Then:
HMS Liverpool returned to the Mediterranean in June to participate in Operation Harpoon, part of the Malta Convoys. While assigned to Force W covering convoy WS 19 on 14 June, Liverpool and the convoy came under attack by at least 38 Axis aircraft.
Just too few escorts stretched too far.