* Before World War II, the Imperial Japanese Navy (IJN) acquired an elegant twin-engine bomber, the Mitsubishi "G3M", which was built in large quantities. It was obsolescent by the beginning of the Pacific War in late 1941, but by that time it had been followed in service by the much improved Mitsubishi "G4M". The "Betty", as it was codenamed by the Allies, remained an important IJN asset through the war -- though in time its lack of armor protection rendered it extremely vulnerable to Allied fighters. This document provides a history and description of Mitsubishi G3M and G4M.
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