Steely-Eyed Missle Man du Jour

John Aaron 

When Apollo 12 launched on November 14, 1969, John Aaron was on shift. Thirty-six seconds after liftoff, the spacecraft was struck by lightning, causing a power surge. Instruments began to malfunction, communications dropped out, and telemetry data became nonsensical. The flight director, Gerry Griffin, expected that he would have to abort the mission. However, Aaron realized that he had seen this odd pattern of telemetry before.

A year before the flight, Aaron had been observing a test at Kennedy Space Center when he had noticed some unusual telemetry readings. On his own initiative, he traced this anomaly back to the obscure Signal Conditioning Equipment (SCE) system, and became one of the few flight controllers who was familiar with the system and its operations. In the case that first drew his attention to the system, normal readings could have been restored by putting the SCE on its auxiliary setting, which meant that it would run even under low-voltage conditions.

Aaron surmised that this setting would also return the Apollo 12 telemetry to normal. When he made the recommendation, "Flight, try SCE to 'Aux'", most of his mission control colleagues had no idea what he was talking about. Both the flight director and the CapCom asked him to repeat the recommendation. Pete Conrad's response to the order was, "What the hell is that?" Fortunately Alan Bean was familiar with the location of the SCE switch inside the capsule, and flipped it to auxiliary. Telemetry was immediately restored, allowing the mission to continue. This call earned Aaron the lasting respect of his colleagues, who declared that he was a "steely-eyed missile man", the absolute highest of NASA compliments.