Apollo 9 crew prepares to participate in Countdown Demonstration Test

S69-25488 (23 Feb. 1969) --- Interior view of the White Room at Pad A, Launch Complex 39, Kennedy Space Center (KSC), during an Apollo 9 Countdown Demonstration Test (CDDT). Astronauts James A. McDivitt, commander; David R. Scott, command module pilot; and Russell L. Schweickart, lunar module pilot, were participating in a dress rehearsal in preparation for their scheduled 10-day Earth-orbital space mission.