Mitsubishi A6M Zero

The Mitsubishi A6M Zero dominated the early Pacific War, combining exceptional agility and unusually long range for a carrier fighter, achieved partly by deliberately sacrificing armour and self-sealing fuel tanks that heavier Allied fighters carried. That lightness gave it an agility advantage Allied pilots initially struggled badly to counter, until new tactics emphasising diving attacks and teamwork, rather than turning dogfights, were developed specifically to neutralise its manoeuvrability edge. Its long range let it escort bombers far beyond what contemporary Allied carrier fighters could manage, extending Japan's early-war strike reach considerably. As the war progressed, its lack of armour and self-sealing tanks became a serious liability against increasingly capable, better-protected Allied fighters.