In the early 1950's it became clear that the Interceptor being developed by Convair would not be operational by its 1954 deadline.  Faced with this problem, the US Air Force decided to procure from Convair a less sophisticated interim interceptor.  This emerged as the F-102A Delta Dagger and the original project was then designated the F-102B.  It is this latter project which eventually became the F-106 Delta Dart.  

On June 17th 1956, the F-102B was officially designated the F-106, reflecting the fact that the original requirements had changed considerably.  All the requirements for speed, altitude and all-weather capability had been increased.  The first prototypes flew in late 56 and early 57.  The performance was somewhat disappointing but this was primarily due to the delays in the power plant development and the subsequent substitution.  However, continual development and improvements were implemented and ultimately, 277 single seat and 63 dual seat aircraft were built and delivered to the Air Force.

The aircraft was the primary air defense weapon for most of the 60's and was kept in service much longer than the original design called for.  After more than 20 years service with the USAF, the F-106s were finally withdrawn from service in 1988.