Evening star., 1961-09-21

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distance to insure against
waves-peered through high
powered binoculars. Most Of
them had witnessed launch
ingS before, even big launch
ingS. But this one was differ
ent-these men were not going
just into space on a proSaic
orbital mission or a lunar fly
by: they were actually going
to land on another world.
The enormous rocket was on
its way now, Is seconds or more
off the pad, a couple Of thou
sand feet in the air and pick
,jng up speed. Strangely, the
whole drama was being played
out in utter silence. A daring
few observers removed ear
plugs to get an idea Of the
sound, but there was none. 1t
would take Is seconds for
sound waves to travel from the
pad to the bleachers.
When the noise finally came,
It arrived as a huge wave, roar
ing up in a smothering mass
of low-regiSter din that was
heard less with the ears than
with the belly.
No Time To Marvel
The three men inside the
spacecraft had not had time to
pause and marvel. Their task,
for the moment, consisted
mainly in monitoring dials and
waiting for the worst of the
accelerative force the "g-
load"-to build up and pass.
To these space veterans the
g-forces were not bad, only
about 4 6 at the peak of first
stage acceleration. Shepard
and Grissom had taken half
again that much on the way
up in Redstone. and all Astro-
nauts took as much as "a g as
a matter of routine training in
the townsville pa centrifuge.
But even moderate forces like
4 G can pretty well conStrain
man.
For 21a minutes the eight
huge FL engines OF the first
stage gulped RP-1 and Lox and
left a fiery trail across the sky.
Then the first stage dropped
off and headed back to earth.
So did the upper stages and
the spacecraft.
SecOnd-Stage Ignition
But there was no consterna-
ton aboard or on the ground.
This had been planned few
seconds of coasting at a speed
well below orbital velocity,
then Second-stage ignition. The
firing came on schedule, and G
forces began to build up again
as the two FL engines of the
second stage took hold. pro-
pelling the II million pounds
of hardware ahead and aloft
with 3 million pounds of
thrust.
The g-force increased only
to az this time, and again
after $50 seconds the powered
flight ceased and the still
earthbound ship began to drop
back. This. too, was according
to plan, double roller
coaster" maneuver before
achieving orbital velocity of
about 1880 miles an hour.
This orbital speed would be
achieved by the third stages
four hydrogen-powered J-2 en-
gineS. At the start Of burning,
the vehicles $4,000 pounds of |
dead weight exceeded the en-
gines' 100000 pounds Of thrust,
but soon thrust exceeded the
ever diminishing weight as
fuel was consumed, and the
rocket darted finally into earth
orbit.
There had been talk early in
the moon-miSSion development
program about going orbital in
two stages and reaching escape
velocity in three. Finally, how
ever, the planners returned to
the original program being
followed on this flight.
Now They Relax
Once in orbit, the crew re-
laxed briefly, knowing their
ship would not now crash back
to earth. The navigator took
over, comparing notes with COL
leagues at the Cape via the
South African station. At the
moment the ship was coasting
in its 100-mile orbit, waiting
to reach the most propitiouS
place for jump-off to the
moon. This maneuver was
called trajectory optimiza-
tion." On today's mission pro-
file, the jump-off point was
over the eastern Indian Ocean
not far from Australia.
The remnant of the big
Nova rocket-the part that was
going on to the moon-now
was hardly bigger than the
old Atlas which orbited the
Mercury AStronauts back in
1862 and 1868, and considerably
less powerful. Six RL-10-A3 |
hydrogen-oxygen engines in a
cluster powered the fourth
stage.
This rocket would accelerate
slowly. but for a long time
eight minutes or so. It's peak
g-load would be only about
half the earth's gravity. This
was to be the crews last "g"
for 21a days, except for brief
moments Of course correction.
Under fourth-stage accelera-
ton the rockets speed built
up to $4,000 miles an hour, the
velocity Of escape. This speed
achieved, the craft was no
longer creature of earth, but
a free-moving celestial body in
its own right. If it should miss
the moon it would become