Which WWII aircraft was substantially redesigned based on direct pilot feedback, resulting in one of history's most successful fighter planes?

Throughout military history, customer feedback has played a crucial role in weapons development and combat system improvements. From ancient times to modern warfare, soldiers' experiences and feedback have shaped the evolution of military technology. This poll tests your knowledge about a famous historical instance where direct battlefield feedback dramatically altered a weapon system that changed the course of military history.

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P-51 Mustang (with the replacement of the Allison engine with the Rolls-Royce Merlin based on RAF pilot feedback)
Supermarine Spitfire (with reinforced wings added after Battle of Britain pilot reports)
Messerschmitt Bf 109 (with improved cockpit visibility based on Luftwaffe ace recommendations)
Mitsubishi A6M Zero (with self-sealing fuel tanks added after analysis of captured American pilot critiques)