Roughly thirty E-boats in sixteen groups approached a northbound convoy, turning its defence into a coordinated system rather than a single-ship duel. Admiral Tovey's dispatch records five destroyers and eight coastal-force units waiting around the most vulnerable approaches near Smith's Knoll. RAF aircraft laying parachute mines provided an early warning, after which destroyer and shore radar enabled commanders to revise the patrol dispositions. MGBs 609 and 610 used hydrophone and radar contacts to stalk one group, remain between it and the convoy, and drive it away when it tried to close. MGBs 607 and 603 covered the likely line of retirement and attacked withdrawing boats, with 607 ramming and sinking one. Only a straggling trawler was lost, showing the value of covering both the attack routes and the enemy's escape route.
Chapter · 17:10-21:25
A coordinated night interception of E-boat groups
A 1943 convoy defence placed destroyers and coastal-force units on likely attack and retirement routes, then used warnings, radar, and aggressive gunboat action to disrupt the E-boats.