Workmen remove the Saturn IB S-IVB-206, the second flight stage for the Skylab 2 mission, from the vehicle assembly building at the Kennedy Space Center. Designed and developed by the Marshall Space Flight Center and the Douglas Aircraft Company in Sacramento, California, the stage was powered by a single J-2 engine, which produced 200,000 pounds of thrust, later uprated to 230,000 pounds for the Saturn V launch vehicle.