British, American, and Canadian yards could surround convoys with cheap escorts, escort carriers, and ASDIC-equipped hunting groups faster than Germany could replace sophisticated submarines. Sinking one escort could reveal a U-boat's position to the rest of the group and invite a concentrated counterattack. The personnel exchange was equally unfavorable because a submarine's crew was unlikely to survive its loss and survivors often became prisoners. Allied surface crews were far more likely to be recovered and returned to service, turning the Atlantic campaign into an attritional contest in force generation as well as shipbuilding.
Chapter · 14:10-15:42
Escort production and crew survival defeated U-boat quality
Mass-produced Allied escorts, hunter groups, and better crew survival imposed an attritional arithmetic that advanced German submarines could not reverse.