At an early stage in the Hustler project, there was some thought on the part of Convair about producing a supersonic transport version of the B-58. Several different supersonic transport proposals were considered. Unfortunately, none of them actually got any farther than the initial concept stage.
The simplest of these projects was a Convair proposal for a special B-58 capable of carrying a modified MB-1 pod that would accommodate five test personnel in comfort. The purpose of this special pod was to explore the problems caused by noise, heat, motion, or psychological stress on various aspects of supersonic passenger flight. If this project had worked out, it is possible that a special passenger-carrying pod might have been built for the B-58 that would be capable of carrying a few government officials or Air Force officers at high speeds during times of national emergency. However, this project was scrubbed before it ever got past the initial concept stage.
In pursuit of a design that might have an appeal to the commercial airliner market, many initial concept studies were carried out by Convair during this period, with the final model being known by the company as Model 58-9. The Model 58-9 exhibited a clear family relationship to the B-58, but featured a long, slim 150-foot fuselage with a pressurized cabin that could carry a maximum of 52 passengers seated two abreast. The aircraft differed from the military B-58 in that the tailcone extended far behind the trailing edge of the delta wing, and featured a separate horizontal tail. The aircraft was to be powered by four Pratt & Whitney J58 turbojets (two under the wings, and two on the wingtips), and could cruise at a speed of Mach 2.4 over a range of 2500 nautical miles. Various other seating arrangements were studied, including three- and four-abreast seating options. Unfortunately, the military showed very little interest in the project and the airlines were at that time undergoing a period of economic uncertainty, and the project was killed before any hardware could be produced.