In article , Allen
Thomson wrote:

STS (Shuttle I)

Which neatly implies a Shuttle II... were there serious plans for a
second-generation shuttle floating around then?

UPRCV - The UPRCV is a partially reusable, series-burn system
with an expected initial operational capability (IOC) In the late
'90s. It consist [sic] of two stages. The flyback booster stage
is twin-bodied (wing sections link the two fuselage sections)
whose design is jointly determined by the Shuttle II and UPRCV
requirements in order to have a common stage for these two
vehicle applications.

Okay... so we're looking at a Shuttle-II-C?

Flyback booster, second stage; the second stage maintaining "plug"
compatability with Shuttle-II. Hmm...

--
-Andrew Gray