With the success of North American Aviation’s F-100 Super Sabre, the company proposed a higher performance variant known originally as the F-100B. As the F-100B design evolved, it became clear that the upgrade would actually be an entirely new airplane, and the project received the designation of F-107A. While there was a significant improvement in performance and load carrying capability, the Air Force chose the Republic F-105 Thunderchief over the F-107. (By Tony R. Landis, Air Force Materiel Command History Office, USAF Image)