Americans
were euphoric over the success of John Glenn's flight in February. The
next Mercury flight was scheduled for May of 1962 with Donald (Deke)
Slayton tapped as its pilot.
On March 15, 1962, it was announced by NASA that
Deke had
been removed
from MA-7 and replaced with Malcolm "Scott" Carpenter. The
medical
community was concerned over an erratic heartbeat that Deke had been
experiencing. With only two months left before the scheduled mission,
there was not much time left to train a replacement.
Even with the limited amount of time left for
training,
the mission
objectives chosen for MA-7 were much more aggressive than those of
MA-6. Carpenter's flight was to become a scientific flight
crammed full of observations, maneuvers, and experiments.
Carpenter named his spacecraft Aurora 7 and it
lifted off
with an Atlas
rocket on May 24, 1962. No problems occurred during the launch.
Inside of the spacecraft, Scott was surprised that the ride on top of
the Atlas was as smooth as it was.
Perhaps this was the quiet before the storm.
Carpenter's flight
would
soon begin to unravel. The mission timeline, chock full of objectives,
was too much for anyone to handle. Astronaut Carpenter fell way behind
with the tasks
that he needed to do.
There were so many
planned maneuvers that the
maneuvering
system fuel
level became dangerously low. For this reason, much of the last orbit
was spent in free drift mode. In that mode the steering jets are
simply turned off. An incorrect switch setting
exacerbated the excess fuel consumption
when a hurried Carpenter neglected to turn
off
the automatic control system during manual operation. At the
start of reentry a concerned Carpenter radioed, "I hope we have
enough fuel."
Retrorockets
are
used to slow the
spacecraft down so that it can leave
orbit and reenter the Earth's atmosphere. The automatic retrorocket
firing system on Carpenter's spacecraft failed. He had to
initiate
the burn sequence manually. Astronaut Carpenter did so, but he
was 3 seconds
late on his action. This delay would cause him to go long and
miss the planned recovery zone by up to 15 miles.
Another problem with Carpenter's setup for reentry
was
that the
required
attitude for the spacecraft during reentry was off by 25 degrees.
This error would add another 175 miles to Carpenter's landing miss.
The performance of the retrorockets was 3 percent low.
This added yet another 60 miles to the length of the miss. So the
accumulated error was around 260 miles when Aurora 7 splashed
down. This distance was out of range of radio communications from
mission control. Astronaut Carpenter was alone floating in the
ocean.
NASA knew before losing communications that Aurora 7 was long
and would miss the recovery zone. The public and newscasters were not
privy
to this information. Concerned listeners knew that that
spacecraft should have already landed. But where was it and was
the astronaut safe? Walter Cronkite who was broadcasting for CBS News
wondered if we had lost an astronaut?
In
time, the public's anxiety would be
assuaged as
they would learn
that Carpenter
was
safe. Recovery of the astronaut and the spacecraft went very well,
albeit hours later than originally planned. The mission was a
success but the errors committed on reentry were something that NASA
vowed never to repeat. Space flight was far from routine.
Aurora 7 orbited
the Earth 3 times with mission duration of 4 hours,
56 minutes, and 5 seconds.
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