This patch by Artist Tm Gagnon illustrates the Saturn V being struck and the lightning following the exhaust contrail to the ground. The Apollo 12 Yankee Clipper and the Mission Control Sigma symbols flank the patch.
It is 6" x 4.25"
As every well-versed space enthusiast knows, the all Navy crew of Apollo 12 experienced the most dynamic launch of a Saturn V.
Thirty-six seconds after liftoff, the spacecraft was struck by lightning, causing a power surge. Instruments began to malfunction and telemetry data became garbled. The flight director, Gerry Griffin, expected that he would have to abort the mission. However, John Aaron serving as EECOM realized that he had previously seen this odd pattern of telemetry.
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 Electronics (SCE) system, and became one of the few flight controllers who was familiar with the system and its operations. For the case that first drew his attention to the system, normal readings could be restored by putting the SCE on its auxiliary setting, which meant that it would operate even with low-voltage conditions.
Aaron surmised that this setting would also return the Apollo 12 telemetry to normal. When he made the recommendation to the Flight Director, "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 Gerald P. Carr asked him to repeat the recommendation. Aaron repeated himself and Carr responded "What the hell's that?" Yet he relayed the order to the crew: "Apollo 12, Houston. Try SCE to auxiliary." Fortunately Alan Bean was familiar with the location of the SCE switch inside the capsule, and flipped it to aux. Telemetry was immediately restored, allowing the mission to continue.
This swift action exemplified the training and teamwork of the flight crew and mission control.