Radar, Albacores, and battle-line control make the Indian Ocean ambush dangerous

Would defeating the Japanese Indian Ocean raid require sacrificing most of the 1942 Eastern Fleet?

Not necessarily; radar-directed night air attacks and a controlled surface ambush could inflict the decisive losses without trading the whole fleet.

The scenario begins with the Swordfish search aircraft whose radar could guide the strike to the correct carrier group and discover the second formation. Alert squadrons could attack the first carriers while the remaining Albacores were redirected, and Japanese night air defense offered little beyond close-range guns. If the Kongos pursued Warspite, she could lead them toward four Revenge-class battleships using radar-directed gunnery. The wider lesson is that night fighting favors the force that controls the timing and geometry of contact; once Japan is reacting to a British plan, its famous night doctrine no longer guarantees the initiative.