What were the worst design mistakes of the two world wars?
Short answerThe Royal Navy's steam-powered K-class submarines are the panel's clearest First World War choice, while the Second World War offers several contenders rather than one uncontested failure.
NotesA steam-propelled submarine had to combine fleet speed, boilers, funnels, and rapid diving in one hull, making the K class an especially unforgiving answer to the fleet-submarine problem. For the Second World War, the panel ranges across ill-judged aircraft roles, turret fighters, top-heavy destroyers, and German ships poorly suited to northern seas. The Bismarck class is described as a powerful collection of ingredients damaged by competing requirements and design-by-committee. Italian and French trial-speed incentives supply another warning: optimizing for a headline speed can leave fire control and fighting performance worse at the very condition being advertised.