High Quality Content by WIKIPEDIA articles! The Shuttle-C was a NASA proposal to turn the Space Shuttle launch stack into a dedicated unmanned cargo launcher. This would use the Space Shuttle external tank and Space Shuttle Solid Rocket Boosters (SRBs), combined with a cargo module that would attach to Shuttle hardpoints (the bipod, etc.) and include the Space Shuttle main engines. Various Shuttle-C concepts were investigated between 1984 and 1995.