The loss at Dunkirk made the E-boat threat an immediate operational problem. The Royal Navy's response combined the 1941 Vosper type, shipborne radar, and air patrols that initially struggled to find fast craft operating at night. The Vosper hull was shaped to aid torpedo launch and give the boat slightly better range. Air-to-surface vessel radar later made nocturnal air hunting more practical, although it first mattered more in anti-submarine warfare than against E-boats. The Royal Navy was assembling a layered counterforce for close coastal fighting.
Chapter · 1:20-3:05
Dunkirk and the need for an E-boat counterforce
The loss of a destroyer at Dunkirk made the danger from German E-boats immediate, pushing the Royal Navy toward faster craft, radar, and night-fighting measures.