The campaign cost an estimated 1,431 merchant ships and roughly 3,600 merchant seamen in British coastal waters. Yet Northern Command calculated 157 ships lost in 63,350 east-coast transits, about 0.244 percent of sailings, which also shows how much traffic survived. One ship's journey through several linked coastal convoys illustrates the hazards along Britain's shores. Unlike ocean convoys grouped by similar speed and handling, coastal formations could mix troopships, tankers, colliers, tiny coasters, landing craft, and tugs hauling Mulberry Harbour components. Their escorts were often only a few armed trawlers and an occasional destroyer, far below the forces associated with Atlantic or Arctic convoys.
Chapter · 38:42-47:48
Coastal convoys faced every kind of wartime hazard
U-boats, E-boats, aircraft, mines, shore guns, weather, and widely different merchant ships made coastal escort work unusually demanding.