Operation C sent almost the whole Japanese carrier striking force into the Indian Ocean to destroy the Eastern Fleet. Attacks on Ceylon, now Sri Lanka, were a means of forcing the British ships to reveal themselves rather than the raid's only purpose. British intercepts initially gave the correct arrival date and allowed Somerville to prepare an ambush. Nagumo's force then ran late, while the British missed the revised timetable and relaxed the expected contact. The episode shows how accurate intelligence can still fail operationally when timing changes faster than the warning system.
Notable Point · 58:20-1:00:17
Operation C aimed to destroy the Eastern Fleet
The Japanese raid on Ceylon was intended to draw out the Eastern Fleet, while a late arrival defeated Britain's initially accurate warning.