dcn@ihuxl.UUCP (Dave Newkirk) (12/31/85)
The flight of Apollo 12 was electrifying, to say the least. Before
it got away on 14 November 1969, the vehicle had been delayed by a
liquid hydrogen fuel tank leak, threatening to scrub the mission.
When that problem was finally whipped, stormy weather on the morning
of the launch portended additional delays. With a long string of
successful flights behind them, however, NASA officials decided to
go ahead and commit Apollo 12 in the midst of a heavy downpour. As
it climbed away from the launch pad, AS-507 was lost to sight almost
immediately as it vanished in to the low-hanging cloud layer. Within
seconds, spectators on the ground were startled to see parallel
streaks of lightning flash out of the sloud back to the launch pad.
Inside the spacecraft, Conrad exclaimed, "I don't know what happened
here. We had everything in the world drop out." Astronauts Pete
Conrad, Richard Gordon, and Alan Bean, inside the spacecraft, had seen
a brilliant flash of light inside the spacecraft, and instantaneously,
read and yellow warning lights all over the command module panels light
up like a Christmas tree. Fuel cells stopped working, circuits went
dead, and the electrically operated gyroscopic platform wnen tumbling
out of control. The spacecraft and rocket had experienced a massive
power failure. Fortunately, the emergency lasted only a few seconds,
as backup power systems took over and the instrument unit of the Saturn
V launch vehicle kept the rocket operating. As the huge Saturn
continued to climb, technicians on the ground help the astonauts weed
out their problems, resetting circuits and making sure that operating
systems had not been harmed by the sudden, unexplained electrical
phenomenon. Apollo 12 went on to complete a successful mission, and
NASA scientists explained later that Apollo had created its own
lightning. During the rocket's passage through the rain clouds, static
electricity built up during its ascent through the cloud cover had
suddenly discharged and knocked out the spacecraft's electrical systems
in the process.
From "Stages to Saturn - A Technological History of the Apollo/Saturn
Launch Vehicles", available from the "Superindendant of Documents", U.S.
Gov't Printing Office, Washington, DC 20402. Order NASA SP-4206, $12.00.
P.S. This is my last installment in the `Tales of Saturn'. NASA
histories also cover the Mercury, Gemini, Apollo, and unmanned
Mars programs, among other subjects.
--
Dave Newkirk, ihnp4!ihuxl!dcn