Grumman F4F Wildcat
The early versions of the F4F were almost completely different airplanes, the F4F-1 being a biplane and the F4F-2 a weak performer that was rejected for service for failing to outfly the Brewster Buffalo (which flew about as well as a real buffalo). The third time was the charm, and it is the F4F-3 and later models, as well as the General Motors built FM-2, that became known as the Wildcat. Its performance was still lacking, and pilots found that the only thing they could really do about the Zero was thank their lucky stars that Grumman built the plane to last.
Cool stuff for Wildcat lovers: