AS-204, the fourth Saturn IB launch vehicle, developed by the Marshall Space Flight Center (MSFC), awaits its January 22, 1968 liftoff from Cape Canaveral, Florida for the unmarned Apollo 5 mission. Primary mission objectives included the verification of the Apollo Lunar Module's (LM) ascent and descent propulsion systems and an evaluation of the S-IVB stage instrument unit performance. In all, nine Saturn IB flights were made, ending with the Apollo-Soyuz Test Project in July 1975.