Lift-off occurred on schedule at 11:22 a.m. EST. Thirty-six seconds later, as
the space vehicle reached 2,000 meters, it was struck by lightning. As Conrad
would later recall, "I was aware of a white light. I knew that we were in the
clouds; and although I was watching the gauges, I was aware of a white light.
The next thing I noted was that I heard the master alarm ringing in my ears,
and I glanced over to the caution and warning panel and it was a sight to
behold." Almost every warning light that had anything to do with the electrical
system was on. Apollo 12, trailing a plume of ionized (and electrically
conductive) exhaust gas, had triggered a lightning discharge. Sixteen seconds
later, at an altitude of 4,400 meters, they sustained a second lightning
discharge. Conrad told Houston, "We just lost the [stabilizing] platform, gang.
I don't know what happened here; we had everything in the world drop out."
At Mission Control, John Aaron, a bright young flight controller in charge of
the electrical system, had no telemetry data on his screen. Aaron had seen this
problem before during simulator runs a year before and knew how to fix it.
Confidently he said, "Flight, try SCE [Signal Condition Equipment] to Aux."
This command was so obscure that neither the flight director, Capcom nor Pete
Conrad knew what it meant. It was Alan Bean who knew where to find the switch,
and moments later telemetry was back.
Despite the unnerving lightning incident, Apollo 12 flew smoothly into a normal
earth orbit. Once the inertial guidance system was realigned and all systems
checked out, they heard the message they'd been waiting for: "Apollo 12, the
good word is you're Go for TLI [Translunar Injection]." What they were not told
was that Mission Control feared that the lighting had damaged the pyrotechnic
system used to deploy the parachutes needed for recovery. If the parachutes
didn't work, they would die during splashdown. Mission Control decided to
continue the mission since this would not affect the moon landing. Once they
relit the third stage and headed for the moon, Conrad said, "Al Bean, you're on
your way to the moon." To which Bean replied, "Yeah. Y'all can come along if
you like."
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