Republic XF-103Conceived in the late 1940\'s as a high speed, high altitude air defence Interceptor and developed through the 1950\'s as a Mach 3 Interceptor capable of operating against Soviet strategic bombers in stratosphere and possibly extending toward the mesosphere, the Republic XF-103 (Model AP-57) was an unsuccessful entrant in the USAF MX-1554 competition that fielded the Convair F-102 Delta Dagger interceptor.
Post-MX-1554, the XF-103 took on the mantle of a research program to prove.
Republic XF-103Conceived in the late 1940\'s as a high speed, high altitude air defence Interceptor and developed through the 1950\'s as a Mach 3 Interceptor capable of operating against Soviet strategic bombers in stratosphere and possibly extending toward the mesosphere, the Republic XF-103 (Model AP-57) was an unsuccessful entrant in the USAF MX-1554 competition that fielded the Convair F-102 Delta Dagger interceptor
