Nottingham's squadron reinforced Third Cruiser Squadron during a North Sea patrol in June 1915, when German submarines attacked the force repeatedly. The armoured cruiser Roxburgh survived a bow hit from U-39 and returned to Rosyth under her own power. The comparison explains why ships designed before the submarine torpedo threat matured did not allocate hull volume to protection in the same way as later ships. Subdivision and dedicated torpedo defences consumed space and forced other design compromises, but combat made that cost increasingly unavoidable.
Notable Point · 24:10-25:21
Why the torpedo threat changed cruiser protection
Roxburgh's survival of a U-39 torpedo shows why subdivision and underwater protection became increasingly necessary design costs.