At one point in Carl Sagan's novel Contact (1985), set c. 1999, the main character hitches a ride into space on a space shuttle:
The President clearly was in favor of her visit [to a private space station], because a place had suddenly been made available on the next shuttle launch, the aging STS Intrepid. ... The aging shuttle fleet was still the workhorse of US government space activities, both military and civilian.
Given that the fleet is said to be "aging", we would assume that the Intrepid had been built in the 1980s in the novel's Universe. Of course, no shuttle with that name was ever built; only one was ever built after Sagan's novel was published, and that was to replace the Challenger.
In 1985, were there still active plans to build more shuttles, beyond the five that existed at the time? Or was this Sagan being optimistic, as was his wont?