Final checkout of the second Saturn flight
vehicle, SA-2, was completed during this report
period at the Marshall Space Flight Center
in preparation for its scheduled flight testing
at Cape Canaveral next quarter.
The recently completed pressure tests cell
facility was placed into operation for the
first time as the SA-2 booster underwent an
extensive testing program in which high pressure
air, helium, and nitrogen were used to check
tanks and mechanical systems for leakage.
Pressure levels up to 3,000 pounds per square
inch above normal atmospheric pressure were
employed in the checkout procedure.
While SA-2 checkout continued, modification
work performed at Todd Shipyard, Houston,
Texas, on the Saturn-carrying barge, Promise,
formerly named Compromise, included addition
of an arched cargo cover, a pilot house, ballast
system, crews quarters, firefighting equipment,
and heating system.
At Wheeler Dam on the Tennessee River, forty-eight
miles from Marshall, a mammoth repair job
neared completion on the lock which had collapsed
last June, forcing a temporary change in Saturn
transportation plans.
The Tennessee Valley Authority announced that
it hopes to reopen the lock by April 23.
Reopening will allow resumption of normal
traffic, including barges carrying Saturns,
beginning with SA-3.
By mid-February of this report period, the
SA-2 flight vehicle had finished its checkout
and was undergoing final preparation for shipment
to the Cape.
Like its predecessor, SA-1, this vehicle consisted
of a live booster, or S-I stage, with inert
S-IV stage, S-V stage, and payload.
On February 16, the SA-2 dummy upper stages
and payload were loaded onto the Saturn barge,
Palaemon.
These were carried as far as Wheeler Dam early
next morning and the barge returned for the
booster.
Loading time for the giant booster at the
Marshall dock was on ten minutes.
At Wheeler, the units were transferred by
land around the broken lock and put aboard
the waiting Promise, which would take them
the rest of the way.
Only about an hour was needed to unload the
booster, move it the one mile over land, and
load it again.
On February 27, the Promise reached its destination,
ending a 2,200 mile voyage, which had taken
it through waters of the Tennessee, Ohio,
and Mississippi Rivers, the Gulf of Mexico,
and the Atlantic seaboard.
At the Cape Canaveral dock, the SA-2 stages
were taken off the barge.
After being transported over land to the launching
pad about two miles away, the booster was
erected on the launch pedestal.
Shortly afterwards, mating of the inert S-IV
stage to the booster began,
followed by the S-V,
and finally the payload, a Jupiter nosecone
and aft section.
The fully assembled SA-2 vehicle was ready
to begin undergoing the long series of checkouts
and preparations, which will proceed its flight
testing next quarter.
Assembly of the booster for the third Saturn
flight vehicle, SA-3, was completed at the
Marshall Center on January 8.
And pre-static checkout of the stage was finished
near the end of the report period.
Checkout work included testing to determine
mass moment of inertia.
The test is based upon application of the
basic spring pendulum principle.
The period of vibration for the booster, suspended
on springs of known spring constants, is determined
by a photoelectric cell and electric timer.
The mass moment of inertia is calculated from
this data plus weight and center of gravity
data obtained by electronic load cells in
previous tests.
[Sound of Engines Firing]
A series of three static test firings was
conducted during this report period with the
SA-T-3 booster, a test stage modified to specifications
of the SA-3.
Later, this test booster was removed and the
actual SA-3 installed for static firing.
Assembly of the booster for the fourth Saturn
flight vehicle, SA-4, began on January 2 and
is expected to be completed this summer.
Marshall’s Saturn assembly area was being
expanded this quarter to make it one-third
again larger.
The expanded area will house a new C-I assembly
station.
One of the two present stations will be converted
for assembly of C-V ground test vehicles.
The additional area will also provide more
office space, a new electrical shop for cable
assembly, and a new clean room facility for
cleaning of tubes and other delicate components.
In the Saturn fabrication area, retooling
is now underway in preparation for structural
fabrication of the SA-5 configuration, or
Block II, tail section, spider beam assembly,
instrument compartment, and second stage adapter.
Work will be performed on five flight boosters
pus two test boosters to be used in structural
and dynamic testing programs at Marshall.
Part of the shop is also being converted for
research, looking toward fabrication methods
to be used on the advanced, or C-V, Saturn
configuration, including out of position,
horizontal, and vertical welding.
A full-scale mockup of the forward and aft
sections of the Block II, or SA-5-type Saturn
booster, is nearing completion for use by
engineers in design verification and also
to familiarize assembly personnel with the
new configuration.
Block II vehicles, which will test live S-IV
stages and boilerplate Apollo spacecraft,
incorporate design changes necessary to accommodate
manned missions.
Modifications include attachment of four large
fins at the tail to increase flight stability.
The launch pedestal will be modified to accept
the fins.
Four so-called stub fins, actually support
structures with aerodynamic faring, are incorporated
to provide additional support points.
The leading edges of three of the stubs will
carry hydrogen ducts through the inside.
Elongated fuel and LOX tanks will hold some
100,000 pounds more propellant for a longer
burning time.
Two large spheres filled with gaseous nitrogen
will replace the forty-eight smaller spheres
used on Block I to pressurize the booster’s
fuel tanks.
The booster’s honeycomb faring used to fare
in between the booster and S-IV stage is mounted
to the eye beam, as are the four retrorockets.
Attaching the upper stage directly to the
spider beam eliminates need for the Block
I upper stage adapter.
Another model, this one built to a scale of
one to ten, depicts a Block II booster and
a cutaway version of the S-IV stage carrying
an Apollo spacecraft on top.
Fabrication of the seventy and 105 inch fuel
and LOX tanks for Block II Saturn vehicles
is now underway by the contractor, Ling-Timco-Vought
at its plant near Dallas, Texas.
Manufacturing begins at this skin mill.
Flat material is properly dressed prior to
rolling it into cylindrical skin configurations.
The tank dome bulkheads are shaped by using
a technique called hydrospinning.
Then, the finished units are carefully inspected
for uniform thickness by using this semiautomatic
vidi gauge.
Prior to inline assembly, each tank section
is trimmed to a specified close tolerance
using this modified lathe.
Z frames are uniformly spaced between the
tank segments, then joined by spot welding
the frames to the segments to this precision
welder.
To prevent assembly line bottlenecks, a portable
X-ray unit is used to check the condition
of smaller parts.
Weld specimens and tank segments are inspected
at each station point of the tank just before
final cleaning and testing.
Meticulous care is exercise during the cleaning
of these LOX and fuel tanks.
Then they are rigorously tested in the hydrostatic
test stand as a final proof of overall reliability.
Activation of Marshall’s Michoud Operations
Plant near New Orleans was underway this quarter.
The huge facility is being made ready for
use by Chrysler Corporation, contractor for
production of future C-I boosters and by Boeing
Company, contractor for development and production
of the advanced Saturn booster, S-IC.
The activation job is being done by the New
Orleans firm of Gerkler, Aber, and Company.
The work consists, generally, of inspecting,
repairing, and returning to usable condition
the vast manufacturing building, covering
nearly two million square feet of floor area
and an adjoining office building plus certain
work on the grounds.
At Douglas Aircraft Company, contractor for
the S-IV stage, initial clod flow tests have
been successfully accomplished with both liquid
oxygen and liquid hydrogen.
Designed to check out the fuel and oxidizer
systems, these tests consisted of transferring
LOX and LH2 from the storage area to the ducting
and valve complexes into the battleship tank.
All aspects of the system performed properly.
This full-scale engineering mockup of the
S-IV stage will be used to functionally check
the vehicle’s electrical system and its
compatibility with ground support equipment.
Many of the mockup’s electrical wiring harnesses
have been completed, and a large percentage
of the wiring has been installed in preparation
for the system’s integration testing program.
Completed in January, this hydrostatic test
vehicle is the first S-IV stage using manufacturing
techniques designed for flight vehicles.
It is currently being put through a series
of hydrostatic filling and pressurization
test operations using water for the test liquid.
On the final test, it will be pressurized
to destruction.
At Marshall, a comprehensive liquid hydrogen
test program indicative of the increasing
importance of LH2 was underway this quarter.
This metal tensile strength test is conducted
by immersing test samples into LH2.
Metals used for S-Iv stage fuel tanks, transfer
ducts, and fuel pumps are tested and evaluated
by moding them in this cryostat.
The cover is then securely attached
and the sample is precooled, by use of liquid
nitrogen, to minus 320 degrees Fahrenheit.
After desired temperature has been obtained,
the liquid nitrogen is drained and the sample
is further cooled to minus 420 degrees by
using liquid hydrogen.
The liquid hydrogen is drained and the sample
is subjected to a tensile strength test.
Since the use of liquid hydrogen in rocket
propulsion is still relatively new, extensive
experimentation is necessary to determine
its compatibility with related components.
At another facility, liquid hydrogen pressurization
tests are run to determine the effect of varying
the temperature of the pressure and gas and
drain time on the tank of the amount of pressurization
gas required.
LH2 is transferred from the storage area through
vacuum-jacketed lines to the test tank, a
double walled aluminum container with vacuum
space between walls for insulation purposes.
The pressurization gas is cooled by liquid
nitrogen when low temperature gas is required,
and heated by a DC current electric heater
when high temperature gas is needed.
Flow rates, temperatures, liquid level, and
pressures are recorded to obtain data, which
indicates the most efficient pressurization
method.
Another liquid hydrogen test facility is now
being used to familiarize Marshall personnel
with handling LH2 in large quantities, and
will be used next quarter for static firings
of Pratt & Whitney RL-10 liquid oxygen-liquid
hydrogen engines.
Cold flow tests, in which propellants are
run through the engine but not ignited, were
carried out this quarter to measure propellant
flow rates, pressures, and other vital functions.
Flow tests had been conducted previously to
transfer the liquid hydrogen from a 7,800
gallon trailer tank to the test stand’s
2,200 gallon run tank.
[Sound of Steam Test]
In conjunction with engine cold tests, steam
evacuation system tests were also run, in
which steam was used to pull a vacuum on the
test stand’s diffuser system, simulating
outer space pressure conditions.
Looking to the future, this artist’s conception
shows a new test stand scheduled to be built
at Marshall for work with liquid oxygen-liquid
hydrogen engines.
This large low pressure environmental chamber
is being used at Marshall to simulate outer
space conditions for the RL-10 engine in a
series of tests studying means of gasifying
pre-ignition liquid oxygen chill down flow
to reduce explosion hazards.
The method being evaluated is the injection
of gaseous nitrogen through a manifold into
the LOX exhaust stream at the engine’s nozzle
exit.
Due to ease of handling, liquid nitrogen is
being used in these tests to simulate LOX.
During flight, before engines start up, propellant
flows are necessary to precool pump and feed
lines.
The liquid hydrogen chill down flow will be
vented overboard and LOX will be exhausted
into the booster S-IV interstage area.
Ambient pressure there may be below the triple
point of oxygen, forming solid particles.
It is anticipated that the oxygen, whether
solid or liquid, can be evaporated using the
sensible heat from gaseous nitrogen injected
just below the thrust chamber.
This test, photographed at about three times
normal speed, shows liquid nitrogen being
exhausted in the form of solid particles.
While a specified gaseous nitrogen flow rate
is injected into the solid stream, the result
is a heat transfer between the gas and solid,
causing evaporation.
After optimum gaseous nitrogen flow requirements
are reached in future tests, the system will
be tested on a hot fire engine at Douglas
or Pratt & Whitney.
Typical of continuing varied research projects
at Marshall are experiments in magnetic forming
and electric discharge forming in a fluid
state.
Ultrafast discharge of voltage from this capacitor
bank and supporting circuits through this
large coil provides the shockwave to form
metal into predetermined shapes.
In preparation for magnetic forming, a blank
piece of metal stock is placed over the coil.
Then the system is energized.
Because of the overload of current, the system
discharges rapidly, and the resulting shockwave
shapes the metal stock.
This method promises to be valuable in forming
metals for advanced Saturn vehicles as well
as providing means for making space vacuum
seals and facilitating fabrication in space.
This equipment is part of a new photographic
instrumentation system, known as fiber optics,
being developed for Saturn.
It will be flown for the first time aboard
SA-5.
Filming during slight will be accomplished
through use of a Millican instrumentation
camera.
The optical cable consists of a bundle of
extremely fine glass fibers arranged so that
when an image is imposed on the face of one
end of the cable, the image is conducted to
the opposite end and reconstructed on its
face.
The objective lens must be accurately focused
to ensure a clear image of the subject.
In this test, a small propeller.
Camera lens adjustments are made by using
the bursite [not sure of spelling] fixture,
allowing for a clear picture between camera
and near-end lens.
The use of optics cables allows cable mounting
other than at the point of image.
Useful applications in flight are filming
the forward sections from the booster, where
several fields of view are required to determine
rate of separation and to study behavior of
the forward section relative to the booster.
The camera is now filming the motion of the
solar cell driven propeller.
The optics cable has carried the image back
to the camera for film recording.
Saturn flights will be monitored by eight
of these systems.
A new approach to attaining three phase, 400
cycle per second power from batteries, is
being developed and refined at Marshall.
This static converter will supply power for
the ST-124 stabilized platform carried aboard
the SA-3 vehicle.
The circuitry consists of a frequency standard
binary countdown flip flops, logic elements,
power amplifiers, output transformers, and
a magnetic amplifier-type voltage regulator.
The static convertor has no moving parts,
consequently, no mechanical wear.
Cabling requirements are reduced as well as
physical size of the battery.
Pound for pound, the static convertor is much
more efficient than a rotating convertor.
This breadboard circuit is a higher powered
version of the static convertor, and when
properly packaged, will be used on future
Saturn vehicles.
Power transistors are used in their most efficient
mode of operation, that is, as switches.
The output voltage wave is stepped and closely
follows a sin wave, having only a ten percent
total harmonic distortion without fluttering.
As research and development for future Saturn
vehicles moved ahead at Marshall and its contractors
across the nation, the ultimate test, actual
flight, was nearing for SA-2, poised for its
attempt to match the spectacular success scored
last October 27 by the first Saturn ever launched.
