All of the valves and settings at the pad had to be set so that the actual loading, the most dangerous part of prelaunch operations, could be conducted by remote control from the Firing Room. Once loading began, there were dozens more procedures, and the process took hours—after all, they were pumping the equivalent of 144 trailer-truck loads of kerosene, liquid oxygen, and liquid hydrogen into the equivalent of a thirty-six-story building.
