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STATION BREAK  March 1991

NASA Presents 1992 Budget Request for Space Station

        NASA last month unveiled a $2.028 billion 1992 budget request for
the Space Station Freedom program, a 7 percent increase over the $1.9
billion 1991 appropriation.
        The requested increase is in line with the 1991
Congressional-mandate that told station managers not to expect more
than a 10 percent increase for each budget year over the long haul.
Congress also told station managers that program funding cannot exceed
$2.6 billion in any year over the next five years.
        "Space Station Freedom is the cornerstone of America's  space
exploration program.  Freedom will be the most advanced and capable
facility ever deployed into space," said NASA Administrator Richard
Truly at a February press briefing.  "It will be able to meet its
priority user requirements: life sciences and microgravity research."
        This budget request and the newly restructured space station are
"within the Congressional budgetary guidelines and consistent with
stated programmatic objectives and our international commitments,"
Truly said.
        What was lost because of budget constraints and the restructure
assessment "is quantity, not quality," said Dr. William B. Lenoir,
Office of Space Flight associate administrator.  "Quantity is the
easiest thing to buy back in later years," so the program has
concentrated on building a solid program that can grow.
        As a means of reducing program risk and cost, the station's new
design features a pre-integrated truss and shorter pre-integrated
modules (see Restructure story, page 1).
        Where possible, station managers will incorporate and build
existing and tested Space Shuttle hardware, rather than research and
build unique advanced technology for Freedom, said Lenoir.  This does
not mean NASA is abandoning advanced technology research, Lenoir said.
However, it does mean slowing the pace, and shrinking upfront research
dollars for projects like the Environmental Closed Loop Life Support
System -- a system that will make station life support systems (water,
oxygen, etc.) relatively self-sustaining once built.
        Another money-saver for the Freedom program entails transferring
research and possible development for the Flight Telerobotic Servicer
(FTS) to the Office of Exploration, Aeronautics and Technology.
        According to President Bush's 1992 budget request, "FTS was
intended to be one of several systems that would provide early robotic
assembly and servicing capability to the space station.  However, the
space station design review has revealed that the importance of having
FTS available in the earliest stages of space station operations has
been greatly diminished.
        "FTS no longer represents a 'critical path' item.  Even so, the
FTS robotic technologies, particularly the end-effector technologies,
are of great importance in the long-term for the space station and the
space program generally.  Therefore, the budget proposes $55 million to
focus the FTS project on technology development, and proposes to the
Space Research and Technology area as part of a broader Automation and
Robotics activity," the budget stated.
        "The overwhelming majority of this budget, 99 percent, supports
programs that have already been approved.  The level of funding sought
by the administration is absolutely essential to keep existing programs
on track, to maintain program efficiency, and to fully realize the
benefits of space exploration," said Truly.
        "It is also required to begin implementing the recommendations set
forth last December by the Advisory Committee on the Future of the U.S.
Space Program, chaired by Norman Augustine.  NASA strongly supports the
overall goals of the advisory committee's report, and we have
undertaken an aggressive review of its specific recommendations.  A
number  [of recommendations] have already been implemented by NASA and
others will follow," Truly said.






Restructure Update

Designers Examine Space Station Pre-Integrated Truss, Shorter Modules

        In a letter to Congress on March 1, NASA Administrator Richard
Truly asked for a 34 day extension to April 8 for submission of the
Space Station Freedom (SSF) restructure assessment study, and he also
requested $200 million in funding for that time.
        "This extension is required to give the Vice President and the
National Space Council (NSpC) adequate time to review the proposed NASA
SSF restructuring plan.  Based on my discussions with the NSpC, the
final plan would be submitted to the Subcommittee [on Veteran's
Administration, Housing and Urban Development, and Independent
Agencies] as soon as possible, but not later than April 8, " Truly
stated in the letter.
        "NASA has made substantial progress since November 1990 in the
restructuring of the SSF, and I am convinced the final proposal will be
affordable; simplify the assembly and operation; reduce the size and
complexity, the number of Space Shuttle launches, and the extrave
hicular activities; meet its principal users' requirements (life
sciences and microgravity research) and maintain overall safety," Truly
said.
        Although the Space Station Freedom program's restructure
assessment is still ongoing, two key features of the modified design
are a pre-integrated truss and shorter, pre-integrated U.S. modules,
Dr. William B. Lenoir, Office of Space Flight associate administrator,
said at a press briefing last month.  Because of federal budget
constraints, this intensive Congressionally-mandated restructure
assessment seeks to cut $6 billion out of the program over the next six
years.
        The newly restructured program would provide a facility that could
be visited by Space Shuttle crews for at least 13 days at a time
beginning in late 1996 and support a permanent crew of four by 1999,
said Richard Kohrs, Space Station Freedom program director.
        This balanced design approach minimizes the delay of the first
element launch, man-tended capability, the international partners,  and
permanently-manned capability, while keeping the ability to conduct
high-power microgravity and life sciences experimentation in the
initial years and long-term life sciences research later on.  "We have
balanced our technical approach against the budget constraints," said
Robert Moorehead, Space Station Freedom Program Office manager .
        "A lot of engineering is behind this [restructure assessment].  We
have taken several months to make sure it would work," said Lenoir.
        "We are not changing what we can provide. We will still be able to
support materials sciences and life sciences.  We will have both power
and people  available.  There will be less capability initially, but,
over time, we can grow," Lenoir said.
        The goals of the Space Station Freedom program would continue to
expand to meet future exploration needs, and hardware would be designed
to allow orderly, efficient growth, he said.
        NASA had asked for $2.45 billion for the 1991 budget year, but
Congress trimmed that budget by $550 million to $1.9 billion.
        Station managers also were told by Congress not to expect more
than a 10 percent budget increase over the long haul, with a peak of
$2.6 billion per year.  This meant trimming $6 billion out of the
program over the next six years.
     "It will be tight.  This is a tough job. Getting $6 billion out of
the program is not easy," Lenoir said.
        Besides meeting the Congressional-mandate not to exceed these
budget constraints, the restructured program also would incorporate
recommendations made by the Presidential Advisory Committee on the
Future of the U.S. Space Program, said Lenoir.
        One of the Committee's recommendations was for NASA to reduce the
complexity of Freedom's assembly and maintenance -- a task station
managers continue to pin down during the restructuring exercise, Lenoir
said.
        Two of the most significant steps station managers plan to take to
reduce cost, complexity, and EVAs is to shorten the habitation and
laboratory modules, outfit them on the ground, and to design
pre-integrated truss segments.
        The move toward shorter modules was based on earlier decisions
made after last summer's weight and power scrub (see August 1990
Station Break), so it makes sense to pull that recommendation into the
restructure assessment, Kohrs said.   Before the summer-long weight and
power scrub and  the current restructure assessment,  the two U.S.
modules were to be 44 feet long, launched virtually empty, and
outfitted in space.
        As a result of  last summer's weight and power scrub and the
restructure assessment,  station managers plan to build 27-foot-long
modules.  This way the modules can be launched completely outfitted,
Lenoir said.  This would mean the complex jigsaw puzzle of the
station's subsystems, such as wires, pipes, and computer systems that
once were to be connected in space, would be put together on the ground
using a system similar to Spacelab processing and outfitting.
Spacelab, which flies in the Shuttle's cargo bay, is a laboratory
dedicated to sciences research in space.
        Realizing the difficulty of assembling Spacelab's complex systems
on the ground, Lenoir said, "There's no way we'd want to do that
on-orbit with the space station."  Building the larger module shells
and then trying to outfit them in space was an overly ambitious and
complex design, Lenoir said.  With the prior design, Lenoir said, "We
were relying too much on EVAs.  People were assuming that EVAs are
easy, but they are not."
        Another major change for the program would call for a
hexagon-shaped, pre-integrated truss structure.  This move alone,
Lenoir said, would significantly reduce program risk.
        Rather than build the truss stick by stick, which would take more
time and would be bounded by the number of EVA hours available,
managers decided to build, integrate and test the truss
on the ground, said Lenoir.



Distributing Gaseous Nitrogen Aboard Station

        Space Station Freedom will provide a unique opportunity for
extended laboratory research in microgravity conditions.  With
microgravity, NASA is faced with a new challenge of controlling
experimental substances and disposal of labora-tory waste.
        Teledyne Brown Engineering (TBE), as a subcontractor to Boeing
Aerospace & Electronics, is developing a system of supplying space
station laboratory racks with nitrogen gas.  While this system may not
be used in the initial years, it is likely that it will be added later
on.  This gas will be used for various purposes including control of
experimental chemical reactions, and purging the user racks of unwanted
substances.
        TBE is developing the Gaseous Nitrogen Distribution System (GNDS)
for supplying nitrogen gas needs.  A number of user racks aboard the
Space Station Freedom U.S. Laboratory eventually will be equipped with
access to the gas for experimental use.
        "Many experiments will need nitrogen gas," said GNDS project
engineer Scott Spearing.  "If it is not supplied, it would have to be
brought from Earth by each user.
        "Much of the weight and room aboard the space station will be
saved by having nitrogen gas plumbed into the system."  The system first
receives nitrogen gas from the Fluid Management System (FMS) in the aft
cone or rear section of the module.  At this point, the gas will have a
temperature of between 60 and 80 degrees F.  A manual shut-off valve
will be in place to isolate the system for maintenance.
        Next is the Pneumatic Manifold Assembly.  This unit is composed of
pressure transducers, a filter, latching solenoid shut-off valves,
pressure regulators and a flowmeter.  The pressure transducer will
measure the pressure of the nitrogen gas, while the filter removes any
particles which may cause damage to the system.  The latching solenoid
valve permits isolation of the pneumatic manifold assembly from the
fluid management system in the event of a component failure downstream
of the valve.
        After the nitrogen gas passes through a second pressure
transducer, pressure and flowrate are controlled and monitored by a
pressure regulator and a flowmeter.  After passage through a third
pressure transducer, the nitrogen branches into the waste gas
management subsystem and the three utility standoffs which are
connected to the GNDS.  Latching solonoid valves and pressure
transducers are located in each of the three laboratory distribution
lines.  These units are important for maintenance or in times of
mechanical failure.  The distribution consists of floor utility
standoffs in the port and starboard sections of the module, and a
starboard ceiling utility standoff.
        A fourth distribution (complete with a solenoid valve) feeds into
the waste gas management system is accessed to depressurize the Gaseous
Nitrogen Distribution System for maintenance.
        The nitrogen gas will flow through the system in stainless steel
tubing with an outside diameter of 3/8 inches.  The wall thickness will
be 0.035 inches.  The gas then branches from the system through
T-fittings and into flex hoses, which deliver the gas to the user racks
in the laboratory.  The user can monitor the nitrogen gas pressure,
temperature and flowrate.  The nitrogen gas distribution pressure will
be between 90-100 psia, with a temperature between 60 and 80 degrees F.
The flowrate will be .50 pounds per minute.
        Check valves and quick disconnects are now part of the path to the
user racks.  The quick disconnects are located at each user rack
connecting point, and have an internal shut-off feature.  This allows
the nitrogen gas supply to be disconnected when a rack is being rotated
away from the wall up to 55 degrees for service, or is removed.


Science Users Meet to Discuss Space Station Restructuring, Other Issues

        The Office of Space Science and Applications recently sponsored
the first 1991 meeting of the Space Station Science and Applications
Advisory Subcommittee (SSSAAS).  The theme for this meeting, held
February 27-March 1, focused almost entirely on the ongoing
restructuring of the Space Station Freedom program and its impact on
the space station users.
        This meeting was key for the U.S. science users, since it followed
the last in a series of major changes to the space station program in
the last year.  It was also the first time that the SSSAAS and the
Space Station Science and Applications Advisory User Board
(SSSAUB) working group have met together.  The SSSAUB will coordinate
all the utilization plans of the U.S. federal science organizations
that have an interest in the space station.  The SSSAUB itself has not
met in over a year due to the long series of changes in the Space
Station Freedom program.
        Restructured station capabilities were discussed for each science
discipline area--microgravity sciences, life sciences, and the
observing and sensing disciplines that intend to someday make use of an
attached payload capability.  Another major topic the group discussed
was the effect of possible changes to the Space Station Freedom data
management system (DMS).  The DMS is a major system to the users
because it packages and transports all data obtained from experiments
onboard the station, as well as captures all instructions relayed from
ground-based stations.
        Other discussions centered on ground payload processing and
integration, with special reference to comparison of Spacelab and space
station processes, on progress in establishing a Small Rapid Response
(SRR) Project Management Office at Johnson Space Center, and on
planning for a second International Science Operations Workshop and the
1991 SSSAAS Summer Workshop.


Ultrapure Water System

        NASA has been challenged to develop future capabilities for
extended manned missions into outer space, and Space Station Freedom's
subcontractor engineers are researching and developing systems for
conducting efficient laboratory experiments in microgravity conditions.
        Space Station Freedom experimental work will be divided into two
areas:  life science and material science.  Life science experimental
work will involve human, animal and plant subjects, while material
science experiments deal with inorganic substances.
        As a subcontractor to Boeing Aerospace & Electronics, Teledyne
Brown Engineering (TBE) is developing the Ultrapure Water System (UPWS)
to purify water as a future station capability to be used in laboratory
experiments.  These experiments will need water free of contaminants
that could cause an unwanted reaction.  Ultrapure water has been
cleaned of minerals, organic contaminants, ionic substances, and
pyrogens.  Pyrogens are substances that could cause a fever if injected
directly into the bloodstream of a human or other animals.
        Ultrapure water will have only one to two parts per billion of
such minerals as copper, chloride and sodium.  The amount of organic
chemicals is expected to be 50 parts per billion and no more than 10
bacteria per liter.  Ultrapure water will be deionized, having low
conductivity.
        "This is something that has never been done before," said to
project engineer Richard Hamner.  "There has never been a high-purity
water reclamation system in space.  Both Skylab and Spacelab took the
water amounts that were needed for the missions.  However, the Russian
space station does reclaim humidity condensate for use as drinking
water.
        "There are great improvements that could be made in the areas of
weight, power, and volume, but volume is the greatest problem we have
at this time."
        The UPWS design requirements are divided into two basic
categories:  the water purification subsystem and purity maintenance.
The principle factors involved in the process of making ultrapure water
are:  organic removal, deionization, filtration, and sterilization.
        A reclamation water line collects the waste water that can be
recycled.  Once in the rack area, the water passes through a shutoff
valve, check valve, and primary filter.  Free gases and vapors are
removed by a liquid gas separator (or phase separator), and sent on to
the waste vapor line.  The phase separator also doubles as a pump to
send feed-water to the storage tanks.   Here, the cleaning process
involves the use of heat and ultraviolet light.
        The water goes through a distillation process for the removal of
undissolved particles.  Three methods of removing these particles are
being studied:  air evaporation, hollow fiber membrane (HFM) diffusion,
and vapor-compression distillation (VCD).
        Air evaporation uses a wick to soak up contaminated water while
warm, dry air is forced through it.  The water and other volatiles are
evaporated off the wick and sent downstream to a condenser.  Studies
are being conducted for TBE on this  diffusion method,the feed-water is
pumped through a bundle of Nafion tubes.  The water is heated, then
routed into the tube network, where the water diffuses through the tube
walls and is then allowed to evaporate on the outer surface.  HFM
distillation studies are being conducted for TBE by Hamilton Standard
Division of United Technologies, located near Windsor Locks, Conn.
        In VCD, the liquid water is forced to the inside wall of a
rotating centrifuge.  Water is evaporated and compressed, causing the
water temperature and pressure to rise.  The warmer vapor is then
condensed and collected on the outer wall of the centrifuge,
transferring the heat back into the remaining contaminated water.  The
VCD technology is being tested for TBE by Life Systems, Inc., of
Cleveland, Ohio.  This process and the HFM process are also being
studied by Boeing and NASA for use in the Urine Processing System.
        After the distillation process is completed, the water enters a
sterilization component.  Here the water temperature is raised to 250
degrees F (121 degrees C) for a period of about 20 minutes.  As a
result, only sterile water will be sent downstream to the remaining
processing steps.  Most of the heat will be retained by a regenerative
counterflow heat exchanger, needing only between 25 and 50 watts to
raise the water to sterilization temperature.
        Elevated-temperature catalytic oxidation processes are now being
studied for organic removal, and are producing encouraging results.
Ultraviolet light oxidation testing (with and without a catalyst) has
been effective on a wide range of organics up to about 3 ppm
concentration.  A process of carbon absorption is also being
investigated.  Pure microbial digestion of organic contaminants is also
being studied.
        Deionization, or the removal of electrically-charged ions will
follow the other purifying steps.  This is because some of the organic
removal processes will convert organics into acids and other ionics
species if the process does not go completely to carbon dioxide and
water.  These ionic species can be removed in this
system by ion exchange.
        There are two types of deionization being investigated:
specially-tailored ion exchange resin beds and Electrodeionization
(EDI).  EDI would have the advantage of using low amounts of power and
energy.  Studies on these two types of deionization are being studied
by Sterimatics, Inc., of Bedford, Mass., a division of Millipore
Corporation.
        With the purification process now completed, the water is sent on
to the ultrapure loop.  The loop keeps the water circulating to reduce
growth of bacteria in the lines and to maintain water purity.  The
recirculation pump sends the water through a UV sterilizer, destroying
any bacteria which passes through
it.  Next is the polisher, with func-tions similar to the
postprocessing steps of deionization and filtration.  In this way,
water is cleaned to ultrapurity each time it enters the polisher.
        Makeup water for the UPWS will come from two sources:  hygiene
water from the environmental control and life support system (ECLSS),
and water from Space Shuttle power cells.  These cells produce water
and electricity by the chemical reaction of hydrogen and oxygen.
        Teledyne Brown Engineering is helping NASA stay at the forefront
of science and technology by providing this and other subsystems for
Space Station Freedom.


Operating Payloads Requires Intense Planning

        How do a limited number of laboratory scientists operate an
unprecedented number of on-orbit experiments and at the same time help
run the space station itself?  In preparing for an orbiting laboratory,
planners must take into account many things that may be taken for
granted on Earth.  In an Earth-based laboratory, facilities can be set
up so that a number of researchers can access them easily and quickly.
There may be few restrictions on space resources, supplies, and
equipment maintenance.  And scientists in an Earth lab are generally
only concerned with maintaining the research equipment, not the lab
itself.
        On the space station, however, not only is interior space limited,
but crew time dedicated to science operations also is limited by the
time the crew must spend on daily station operations.  And Freedom will
require the regular operation of up to ten times the number of
equipment racks currently operated on Spacelab, with only slightly more
crew at best.  Limited resources must be carefully scheduled and
managed.  Since Spacelab missions are relatively short (usually six to
ten days), it is feasible to gather all the investigators into one
payload control center for the duration of the mission.  With the space
station, however, payload experimentation may go on for a number of
days, months, or years.  It is, therefore, more efficient and
productive for investigators to manage experiments from their home
institutions.
        The Office of Space Science and Applications (OSSA) has just
released an "operations concept" that outlines the objectives and
approaches to be used to keep experiment operations running smoothly.
The overall objective of this strategy is to provide a cost-effective
and mission-effective operations structure that will accommodate a
number of science users around the globe.  Additional objectives that
support this major strategy are:  to promote an integrated science
planning interface with the space station program; to allow scientists
to effectively participate remotely in real-time operations; and to
provide a flexible structure to accommodate the natural evolution in
individual user operations capabilities.
        The OSSA science operations concept is composed of three main
elements:  an Integrated Science Operations Center (ISOC), science
discipline operations support elements, and the science investigators.
Within this framework, operating elements have the flexibility to
define their own levels and manner of operation.
        The ISOC provides a unified interface to the station program for
U.S. science operations, coordinates OSSA's remote scheduling and
operations activities, and provides varying levels of assistance to the
investigators.  The ISOC interfaces directly with the station program's
Payload Operations Integration Center (POIC).  The POIC will integrate
all space station payload operations, including those of international
users.
        Discipline Operations Support is support for on-orbit operations
of individual science discipline instruments or facilities, with
primary responsibility for scheduling, instrument/facility operations,
and managing related data and communications flow.
        Investigator facilities are those distributed institutional
locations from where science investigators can monitor and control
experiments; communicate with the onboard crew; receive, process, and
analyze data; and support the planning and scheduling process for
payload operations.
        During the initial use of Freedom, science operations will be
conducted from a limited number of major operations facilities.  As
with other aspects of science utilization planning, this initial
configuration will evolve as the space station matures and as OSSA
builds and operates more payloads.



NEWS BRIEFS

Flight Test

     In April, astronauts will step out the Space Shuttle Atlantis'
door 243 nautical miles above Earth for the first NASA space walk in
five years.
        Shuttle mission crew members will conduct the Crew and Equipment
Translation Aid (CETA) flight experiment in the Orbiter's payload bay.
The two crew members will try three different methods of propelling a
small cart along rails in the bay in an effort to identify the best way
to move on the exterior of Space Station Freedom.
        CETA is a small cart that runs along a track that can be built
into the Space Station Freedom truss.  Astronauts would ride prone on
CETA, and could pull equipment along behind them.
        But how to propel the cart, how much stress the various methods
of movement would put on the  truss and the astronaut, and how fast it
can be comfortably and safely moved are questions to be studied on the
April mission.
        The cart will be mounted on a track in the payload bay, skirted by
two handrails for half of the bay and by one rail.
        The astronauts will move the cart in three different fashions:
lying prone, one crewman will pull himself along the track hand over
hand; with the astronaut angled upward slightly, the cart will be
changed to accommodate a lever that can be pumped to move it up and
down the track, much like an old railroad handcar; and also with the
crewman at about a 45-degree angle, the cart will be propelled by
hand-pushed pedals similar to a bicycle -- the pedals will generate
electricity to drive the cart.

Contract

     NASA's Kennedy Space Center, Fla., last month awarded Metric
Constructors, Inc., Tampa, Fla., a $56.2 million contract to build the
Space Station Processing Facility (SSPF).
        Under the terms of the fixed-price contract, Metric Constructors
will build the 457,000-square-foot facility to be used as the central
preflight checkout and processing point for Space Station Freedom
elements.
        The three-story building will include communications and
electrical control areas, laboratories, logistics staging areas,
operational control rooms, office areas, and a cafeteria.
        Construction of the processing facility is set to begin on or
about April 1 and the building should be ready for occupancy within
1080 days of the SSPF groundbreaking.