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STATION BREAK    VOL. 4 NO. 5, MAY 1992

SENATE CONFIRMS GOLDIN AS NASA ADMINISTRATOR

        The Senate confirmed Daniel S. Goldin as NASA's ninth
administrator last month.  During his confirmation hearing before the
Commerce, Science and Transportation Committee, Goldin painted his
vision of tomorrow's NASA for the senators .
        Early on, Goldin touted Space Station Freedom as one of his four
core values for NASA.  "If confirmed, I will work with Congress to
establish the president's goal to deploy Space Station Freedom and
Mission to Planet Earth by the end of the decade."
        "Given that and given that humans are destined to explore space
and reap ultimate rewards for new opportunity, for commercial, for
mankind -- to make the life we have better -- I believe it's necessary
first to understand the interactions of the human species in space.  We
don't want to do it as just a 'spectacular.'  You know, putting an
astronaut in a capsule to see how far he could be launched and bringing
him back.  No, we really want to do it scientifically -- to truly
understand what happens to human physiology.  What happens to calcium in
the bones?  What could we really do to protect humans from space
radiation?
        "Toward that end, I think we need continued human presence in
space on a scientific basis, not a spectacular basis.  I believe Space
Station Freedom fits in line with the core values I have stated . . .
The goals and objectives of space station, I think, are correct.  Space
Station Freedom will allow the continuous interaction of humans in the
space environment.  Permanent human presence is very, very critical . .
.  The space station is the right thing to do."
        After addressing Freedom as one of four equally important goals,
Goldin told the senators he also expects NASA to excel in its Mission to
Planet Earth, a program to study Earth's environment; to expand its
program of looking at other planets, moons and asteroids; and to
recommit NASA to continue to lead America in aeronautics.
        A self-described space enthusiast, Goldin told the committee and
later NASA employees, "I can't tell you what an honor this is for me,
and how happy I am to come back home to NASA.  Over  30 years ago, I sat
down with my father and we filled out an application for the Lewis
Research Center [Ohio] that started my career in civil space.
        "Thirty years ago I responded to John Kennedy's call for human
space exploration and I dedicated my life to the space business . . .
To be asked by the president to lead NASA is a great honor."
        As a symbol of America's competitive spirit, NASA is the standard
by which all other nations of the world measure their space programs.
"NASA is an investment in America's future."
        In announcing the nomination of Goldin, President Bush said, "Dan
is a leader in America's aerospace industry and a man of extraordinary
energy and vitality.  Dan Goldin will ensure America's leadership in
space."
        In his opening statement to the committee, Goldin said, "Thanks to
the dedication of NASA employees and capable leaders of people like Jim
Fletcher, Jim Webb, Jim Beggs, and especially Admiral Dick Truly, NASA
has taken this nation where no other nation has been able to go.  We
have explored every planet in the solar system, save one [Pluto].  We've
left our footprints on the face of the moon.  We have pushed the edge of
technology to maintain U.S. leadership in space and aeronautics.  We
have made powerful contributions to American competitiveness . . .  The
National Aeronautics and Space Administration must continue its
leadership in the mastery of air and space.  NASA must push the edge of
technology to enable the successful execution of our mission.  NASA must
continue to transfer technology to the private sector to ensure
America's competitive posture.
        "Mr. Chairman, through NASA, we look inward to our own planet and
the workings of our fragile Earth.  At the same time, NASA looks outward
to the heavens, preparing for the decades ahead as we explore our own
solar system and beyond.  NASA takes this nation to the leading edge of
technology.  It challenges our young people to master math and science.
And it forces better relations with people who inhabit our small
planet."
        To achieve these lofty goals, however, Goldin told the committee
that NASA's funding instability must end.
        "The instability in the space program not only hurts the morale at
NASA, it hurts the morale of NASA's support contractors," Goldin said,
drawing from his experience at TRW with the now-defunct AXAF program.
        "The program had starts and stops.  At the dawn of one of the
program's 'golden' achievements -- the accomplishment of grinding the
world's two largest X-ray mirrors, a congressional milestone set years
in advance and beat by six days, the program was delayed, stretched and
then scratched," Goldin said.
        "As a result, minor layoffs were necessary," Goldin said.  "It
just takes a little bit of life out of an organization.  These people
dedicate themselves.  They work day and night.  You go by NASA or any of
the contractors on a late evening, a Saturday or a Sunday and there are
these dedicated human beings pouring their guts out for what they
believe is their contribution to society.
        "So when we have this instability, and we have budget problems, it
rips the heart out of the program.  It takes a little life every time
there's a delay, a slip, a budget problem," he said.
        "The thing that I see as absolutely essential is that we have
vigorous interaction and once we have an agreement -- we really strive to
hold to that agreement on both sides."


TAKING PHYSICAL FITNESS TO NEW FRONTIERS
STATION-RELATED CYCLE STABILIZER TO UNDERGO SHUTTLE FLIGHT TEST

        A major challenge in designing future manned space missions may
now be resolved, thanks to some new equipment developed by NASA and
Lockheed.
        The challenge is the incompatibility of physical exercise and
microgravity science.  Astronauts must exercise during their missions,
but sensitive microgravity experiments conducted on those missions need
a spacecraft environment free from disturbance.
        The NASA/Lockheed solution is a platform that supports the
exercise equipment yet cancels out the vibrations, allowing astronauts
to work out strenuously without interfering with science experiments.
The device is called the Isolated/Stabilized Exercise Platform (ISEP).
The first flight-ready stabilized platform was delivered to Johnson
Space Center in January.  Its Shuttle debut is planned for June, in the
middeck of the Space Shuttle Columbia.
        Dr. Damon Smith, Lockheed's stabilized platform chief scientist
and project leader, said, "It's desirable that astronauts on the longer
Shuttle missions perform hard aerobic exercise daily.  Without this
exercise, the prolonged absence of gravity could affect the crew's
ability to stand upright without dizziness when they return to Earth."
        Typically, orbiting astronauts have exercised on a bicycle or
treadmill mounted to a Shuttle bulkhead.  "When there are no sensitive
experiments aboard, this is not a problem," Smith said, "but in the
presence of microgravity research such as protein crystal growth, this
amount of activity interferes.  It's important that the Shuttle
astronauts get their exercise and the experiments to be protected."
        Regular aerobic exercise will be especially important for space
station crewmembers or voyagers to Mars, who also must counteract the
prolonged effects of weightlessness on their skeletal systems.  Bones
lose calcium during long periods without gravity, and exercise is an
effective countermeasure to deal with this loss.
        "The conflict between the medical need for exercise and the
sensitivity of microgravity experiments has challenged space planners
for some time," Smith said.  "We think we've solved the problem with the
ISEP."
        Lockheed designed the first stabilized platform for use with an
ergometer, a stationary-cycle device built by the European Space Agency.
Future designs will accommodate a treadmill and a rowing machine.
        The June flight of Columbia will be STS-50, a 13-day microgravity
research mission called United States Microgravity Laboratory 1.  USML-1
will be the longest Space Shuttle flight to date.  Crew exercise is a
top priority.
        "TV viewers worldwide may be able to look in as the astronauts go
through their daily exercise regimen on the ergometer, which will be
mounted on Lockheed's ISEP," Smith said.
        The stabilized platform consists of four rectangular stabilizers
attached vertically to a frame, which rests on shock absorbers called
isolators.  The ergometer attaches to the frame.  The stabilizers hold
each corner of the frame stationary.  Smith explained, "A motor inside
each stabilizer uses inertial stabilization to counteract the
disturbances caused by the exercise."
        Without stabilizers, a crewmember peddling a stationary bicycle
can produce as much as 100 pounds of force, which far exceeds the
allowable microgravity disturbance limits set by NASA.  With Lockheed's
stabilized platform system, the exercise is expected to cause less than
one pound of disturbance force on the Shuttle middeck.
        From concept to delivery, Lockheed produced the flight equipment
very quickly.  Smith said, "We came up with the design only last year
and, in about nine months, built, tested and shipped the hardware to
Johnson Space Center.  We certainly believe this product meets the
requirements of NASA's microgravity and life-sciences offices.  The
successful use of stabilized platforms on USML-1 will show that the
needs of both the crew and the microgravity scientists can be
accommodated simultaneously on the same spacecraft."
        Smith's group is part of the Space Station Freedom office at
Lockheed.


JSC PUTS 'LIFE BOAT' TO WAVE TEST

        The time is September 1999.  The Space Shuttle stands poised on
the launch pad at Kennedy Space Center ready for the final baseline
assembly mission for Space Station Freedom.
        The cargo for this flight, known as Mission Build-17, is the key
to making the orbiting laboratory truly self-sustaining.
        Tucked in the payload bay is the Assured Crew Return Vehicle
(ACRV), which will be docked to the station and allows Freedom's crew
rapid escape from the facility in the event of an emergency.
        With the 'life boat' in place, the Shuttle can now undock and
return to Earth leaving an international crew of four to occupy  the
orbiting outpost conducting experiments in life and materials sciences.
        This BOAT set sail, as it were, in March in the Weightless
Environment Training Facility (WETF) at Johnson Space Center.
        BOAT, which stands for Buoyant Overdesigned ACRV Testbed is a test
article for the space station return vehicle.  It is designed for three
phases of testing during the next several months ending with water
testing at the Offshore Technology Research Center at Texas A&M
University.
        The test article was designed, developed and built in-house for a
fraction of the cost of outside work, said Brian Kelly, ACRV project
office lead on the BOAT test.
        The full-scale, weight-representative test article will undergo
three phases of egress and flotation testing during the next two months.
Phase 1 consisted of dry-ground evaluations of personnel validating
egress procedures.  Phase 2 will be divided into unmanned and manned
testing in the WETF.  This phase is planned to begin later this month.
        The final test phase is scheduled for late April and May at Texas
A&M using a high-fidelity wave machine that was built to test platform
design and stability for off-shore oil rigs.  NASA will be one of the
first big clients to use the Offshore Technology Research Center, Kelly
said, and will concentrate on open-water crew rescue simulations under a
variety of sea-state conditions.  The Offshore Technology Research
Center, which consists of 48 computer-controlled hydraulic actuators
that create and control the wave state, will allow the team to evaluate
the ACRV testbed under controlled conditions.
        "In the ocean we can't control the wave state and safety is a
concern for the early testing," he said.
        The BOAT was conceived during a meeting about a year ago when
several people joked about using Waterworld's facility near Astroworld
for such testing because its wave pool could generate "sea-state"
conditions.
        Further analysis demonstrated that the device would come too close
to the bottom of that pool,     and the Waterworld idea was scrapped.
        "Waterworld was agreeable, but our folks doing the analytical
modeling said we would get within a foot or foot and a half of the
bottom.  That was too close," Kelly said.
        It was about this time that Bob Ess, principal investigator for
the project from Engineering's Navigation, Control and Aeronautics
Division at Johnson proposed a home-built wave tank and test article to
at least demonstrate the concept could work.
        Ess along with then co-op Scott Tamblyn, built a wooden sub-scale
wave tank in his driveway.  The wave generation unit was built using an
old washing machine motor.  Four eight-inch-diameter BOAT test articles
were built for use in the sub-scale tank by Paul Romere who works in the
same branch as Ess.  Both cost a fraction of what a typical test article
would have cost.  The wave tank cost less than $1,000 and the BOAT sub-
scale test article cost less than $100.  By comparison, the wave tank
would have cost about $30,000 and the test article would cost about $400
if produced commercially.
        Ess said he began sketching a picture of the wave tank and bought
a used transmission for a washing machine.  The home wave tank was 24
feet long, four feet wide and two feet deep.
        The people at the store where he bought the washing machine motor
were skeptical when he told them what the unit was for.  "They didn't
think it would work as a wave machine," he said.
        But the home unit did work and eventually Ess and his coworkers
moved it to Building 220 for further testing.  Using the small wooden
BOAT test articles, they developed restraining devices that would keep
this unit from contacting the side of the wave tank.
        "This is a perfect example of these people using their own
ingenuity for the benefit of the overall project," Kelly said.
        The sub-scale BOAT and wave tank testing enabled lead designer
Stephen Munday to arrive at the design of the full-scale testbed now
undergoing testing.
        "The Man Systems Division brought us in to help in the design to
make sure the test article would be dynamically correct," Munday said.
        As the chief designer, Munday also had responsibility for ensuring
the BOAT could simulate three different types of ACRV.
        By changing the skirt configuration and moving the center of
gravity, the BOAT can simulate an Apollo-type spacecraft Station Crew
Return Alternative Module, allowing water to cover the heat shield, and
a Station Crew Return Alternative Module where the shield is protected
from water.
        The word "Overdesigned" in the Buoyant Overdesigned ACRV Testbed
simply means the extra mass that was required in the design to better
approximate real- vehicle handling characteristics.  The testbed weighs
about 9,500 pounds.
        "We have a two-pronged purpose to the testing," Kelly said.  One
is to create a database of
vehicle handling characteristics to assess the vehicle's dynamics on the
water.  The second is to identify requirements for a water egress by a
crew given such a landing, Kelly said.
        Egress data gathered under various sea states will be used by the
ACRV Project Office to determine if a land or sea touchdown is the best
course to take.
        "The tests will help determine which landing mode is more
feasible.  This will include the assessment of the type of parachute to
use based on the gravity constraints on the human body," Kelly said.
        While the BOAT testing is under way, co-worker Brian Ross is busy
creating computer simulations of the hydrodynamic process for use in
future programs that may require similar testing.
        To demonstrate their faith in the workmanship, Ess, Munday and
several others involved in the BOAT project will serve as the living
test subjects for the egress tests in Johnson's weightless environment
test facility and at Texas A&M.


BOEING TESTS CRITICAL STATION CONNECTION

        When 40 tons of hardware come together in the vacuum of outer
space, you want to make sure they stay together for good.
        Engineers at Boeing Defense and Space Group in Huntsville, Ala.,
are duplicating conditions on orbit that would play a role in connecting
-- for good -- modules and nodes for Space Station Freedom.  Boeing is
building the orbiting laboratory's pressurized areas for NASA.
        Testing is under way on large developmental modules and nodes,
much like those that will be launched in about four years.  Suspended
from beams, the developmental structures are being subjected to
simulations of the space environment -- vibration, heat and pressure.
The information that results will be essential to the construction of
flight structures.
        "Because of gravity, copying the way hardware will behave in space
is tough on the Earth's surface," said Doug Stone, chief engineer for
Boeing work on the space station.  "The processes we're using here are
the best thing we've found to help us make the hardware we've built move
like it would in space.  This series of tests will prove Space Station
Freedom's pressurized modules can be joined on orbit."
        The space station comprises several modules and nodes that will be
launched in the Space Shuttle's cargo bay and joined, or "berthed," once
they reach space.  This critical connection is the focus of the test
being conducted by Boeing at the NASA Marshall Space Flight Center over
the next eight months.
        According to deputy systems test manager James Dean, the simulated
berthing test is the first time that major structures -- a node structure
and a module representing the laboratory or living quarters -- are joined
in various configurations.
        Two full-sized structures will be suspended from the beams, Dean
explained.  Technicians will be able to move the whole operation in a
number of positions to simulate the way the modules would be put
together in space.
        "The structures will be joined with berthing mechanism hardware,
and then pressurized in different combinations," Dean said.
        During these procedures, Boeing will monitor nearly 2,000 channels
of tiny sensors to make sure the actual flight structures stay together
for 30 years.  The tests will be used to prove that:
        *       The station responds properly to vibrations caused by
Shuttle docking;
        *       The berthing mechanisms perform their jobs; and
        *       The structure is capable of sustaining internal pressure at
"one atmosphere," or 14.7 psi.
        The data Boeing gets from the berthing test will "freeze" the
design; then the actual qualification test and flight modules will be
built.


PROTOTYPE ADVANCED TECHNOLOGIES FOR SPACE STATION FREEDOM

        An experiment on a Space Shuttle mission encounters unexpected
test results.  In response, a new set of experiment procedures are
automatically generated by an expert system called the Astronaut Science
Advisor, which guides the mission specialist investigating this new
phenomenon.  Scientific productivity is increased in the face of an
unanticipated event.
        During STS-43, the crew scans online procedural checklists and
manuals, checks their electronic mail, and is alerted to significant
events by "intelligent" wristwatches.  This office-like ability exploits
the potential of portable computers to increase crew productivity.
        In the laboratory, an engineer reaches out to touch a robotic arm.
The robot "senses" this action and reacts by moving its arm out of the
way, and continues to avoid repeated attempts to grab its arm.  Sensors
covering the robot's arm provide a practical and reliable collision
avoidance capability that avoids the intensive computational
requirements of conventional methods.
        What do these events have in common?  They are all examples of
technologies being pursued by the Level I Engineering Prototype
Development (EPD) activity, managed by the Space Station Engineering
Division at NASA Headquarters.  The engineering program identifies cost,
schedule and technical risk reduction options by demonstrating and
integrating key innovative technologies into the baseline program.
        Articles presenting engineering program supported tasks have
appeared in the last four issues of Station Break and will continue to
be featured in upcoming editions.  In this issue, a companion article
(page 7) highlights an engineering program task that is developing
advanced monitoring and fault management capabilities for the space
station thermal control system.
        Engineering program tasks will lead to increased system
productivity and reliability, reduced extravehicular activity (EVA) and
intravehicular activity (IVA) task times, and help constrain operations
and life cycle costs attributable to technological obsolescence.
        These efforts will enhance Space Station Freedom's flight and
ground systems capabilities by prototyping applications of advanced
technologies and transitioning successful prototypes into the baseline
program.  This is accomplished by building user/technologist teams
within flight and research centers, developing applications using a mix
of conventional and advanced techniques, addressing transition and
implementation issues, and evaluating performance and documenting design
accommodations for technology insertion and implementation.
        The approach also leverages research and advanced technology
development programs within NASA and other government agencies.
Specifically, cooperative arrangements have been pursued with the Office
of Aeronautics and Space Technology, the Office of Space Systems
Development, Advanced Programs Development, the Office of Space Science
and Applications, Defense Advanced Research Projects Agency and other
Department of Defense programs.
        Advanced automation applications are being developed for selected
space station distributed systems and control centers.  These
applications will provide a range of support in automated system-status
monitoring, maintenance of safe operational modes, and system
reconfiguration in response to operational demands.
        Advanced automation applications  rely heavily on knowledge-based
systems to augment conventional techniques for fault detection (sensing
that a problem has occurred), isolation (locating the source of the
problem) and recovery (reconfiguring the system to alleviate the
problem).
        The Astronaut Science Advisor, featured in the February Station
Break, and the Thermal Control System advanced automation task, featured
in this issue, are just two examples of the increased productivity and
improved management of available resources this technology can produce.
Each application provides a powerful user interface to support advisory
mode interactions.  The primary benefits of these techniques are
increased systems reliability through improved system monitoring,
enhanced fault detection and isolation capabilities, and increased
productivity for control center personnel and Freedom crewmembers.
        The computer and network architectures of Space Station Freedom's
data management system present a complex, multi-processing environment
operating under demanding real-time performance constraints.  The data
management system baseline is being analyzed to provide increased
performance and reliability and to determine long-range growth options.
        Advanced architectures are being evaluated with respect to
existing and proposed processors, network and connectivity options, and
system management software.  Computer hardware and software interfaces,
such as "intelligent" wristwatches, are being evaluated on Shuttle
flights to resolve user interface issues for the space station
environment.  Additionally, advanced mission planning and scheduling
systems, such as the COMPASS system (April 1992, Station Break), are
being developed and demonstrated for use aboard Freedom, as well as on
the ground.
        The amount of software being developed to support Freedom's flight
and ground systems is dramatically increased over that of past programs.
The space station has recognized the software development and
maintenance process to be one of the most critical elements of the
program.  The engineering program is working to improve the quality and
productivity of large software projects by pursuing the development of
the software tools, methodologies and environments needed to support the
design, development and maintenance of Freedom's advanced software
applications.  This software enhancement effort has already produced the
Failure Environment Analysis Tool (FEAT), featured in the March Station
Break, which will help NASA's engineers apply a common approach to
assessing a system's susceptibility to failures.  The dramatic increase
in software requirements is reflective of the long-term operational
demands of the Freedom program.  These demands strongly impact the
training of crew and operations staff.  The use of Intelligent Computer-
Aided Training (ICAT), which was featured in the January issue, provides
the ability to personalize training by reducing the overhead involved in
setting up training environments, scheduling classes and developing
simulations.  The engineering program, jointly with the Office of Space
Systems Development's Advanced Program Development office, is
cosponsoring the design, development and testing of general
architectures for ICAT so that the large costs of developing, delivering
and maintaining training systems can be avoided while enhancing training
efficiency, uniformity and verifiability.
        Space Station Freedom will herald the routine use of robotics in
space to assist the crew with routine and, in some cases, potentially
risky operations.  Key hardware and software technologies are being
advanced to improve operator-telerobot interfaces and to enhance
telerobotic control.  A breakthrough technology for proximity sensors,
demonstrated in our earlier example, has been developed to improve
collision detection and avoidance, enabling telerobots to stop, back
away from, or work around objects such as payloads or extravehicular
activity crewmembers.  These technologies will allow telerobots to do
more work in less time, with greater safety and reliability.  The
increased use of telerobotics reduces the need for EVA, while enhanced
control reduces the IVA time required to perform telerobotic tasks.
        As a result of the efforts of the EPD activity, the Space Station
Freedom program is acquiring mature technologies, tools and applications
for key systems.  Application of these technologies will lead to
increased system productivity and reliability, and restrain operations
and life cycle costs due to technological obsolescence.  In the coming
months, tasks supported by the engineering program activity will
continue to be highlighted with each new issue of Station Break.


"INTELLIGENT" THERMAL CONTROL SYSTEM PUT TO THE TEST

        More than 50,000 watts of power will flow through Space Station
Freedom's electrical circuits.  This electricity, produced by the
station's solar arrays, provides the power to run all of the motors and
mechanisms necessary for the crew's comfort and survival, to operate all
of the scientific equipment and experiments, and to operate all of the
station's own subsystems.  Fifty thousand watts is enough to power more
than 30 portable electric heaters, and practically every watt of
electricity ends up as heat -- heat from lights, fan motors and
compressors, from electrical resistors and transformers and other
electrical parts too numerous to count.
        Temperature control may not be the most glamorous of functions,
but it is of fundamental and vital importance to Space Station Freedom.
Temperature control involves multiple subsystems to perform a few basic
functions:  to add heat where it is needed, to collect excess heat, and
to reject the excess heat to space.
        The central facility for temperature control is the External
Active Thermal Control System.  This system pumps a coolant around the
station through a network of tubing.
        Heat generated within the crew quarters, by the various payloads
and their experiments, and the station's engineering systems is
transferred to radiators located on the outside of the station, then the
heat is radiated into space.  The space station's thermal system will be
required to handle much larger heat loads and operate for a much longer
time than that of any other spacecraft.
        Earlier manned space programs had relatively short mission
durations, measured in hours and days, as compared to the multi-year
design life of Freedom.  Manual monitoring worked well for those short
missions, but is not an attractive solution for Space Station Freedom.
An automated monitoring and control system can constantly monitor a
larger number of parameters than human flight controllers.
        Automated systems and tools will play a crucial role in decreasing
the cost of system monitoring during the operation of Space Station
Freedom.  The Thermal Control System Automation Project (TCSAP), being
performed by the Crew and Thermal Systems Division and the Automation
and Robotics Division at NASA's Johnson Space Center, with support from
the Space Station Level I Engineering Prototype Development activity, is
developing advanced monitoring and fault management capabilities for the
Space Station Freedom thermal system.
        The thermal control system automation project is developing a
knowledge-based system (KBS) to monitor, control, and perform fault
management on the Space Station Freedom thermal control system.  This
system represents a mechanism for storing knowledge about the systems
and for displaying the appropriate information, in this case to the
ground flight controller, when a fault has been detected.  Early NASA
research, sponsored by Office of Aeronautics and Space Technology
(OAST), on advanced techniques for the automation and detection of
faults in systems, showed that the expense of testing advanced fault
management software against actual hardware could be prohibitive.  To
minimize the expense of testing the knowledge-based system against
actual hardware, thermal control system automation project is developing
a high-fidelity simulation of the thermal system.  The simulator assists
in the development of the knowledge-based system by providing a
mechanism for gathering information about the thermal system and
generating data for testing new capabilities.
        The knowledge-based system uses a combination of conventional
programming, expert system technology and model-based reasoning to
provide powerful and flexible diagnostic expertise to assist the flight
controller in managing the thermal system.  The knowledge-based system
tracks sensor readings and compares them to predicted values generated
by the model-based reasoning portion of the system.  It validates
sensors and diagnoses failures based on any inconsistencies found
between the predicted and actual state of the system.  An intelligent
display allows the flight controller to efficiently monitor both the
knowledge-based system's reasoning status and the status of the thermal
system's hardware.  As faults are diagnosed, the knowledge-based system
will alert the flight controller and display time histories of
instrumentation pertinent to the diagnosis.  Event timelines allow the
flight controller to evaluate the sequence of events leading to the
failure.
        The project's high-fidelity simulation can be used for a variety
of other uses within the Space Station Freedom program.  For example,
crew and flight controller training can be enhanced with a high-fidelity
simulation of the thermal system.  The simulator can provide sensor data
representing the system under both normal and abnormal conditions.
During the development of the thermal system's operating procedures, the
simulator can evaluate alternative operator actions or activities. It
also can be used for analysis of ground test results.
        The thermal control system automation project recently
participated in monitoring the ground tests of early design hardware for
Space Stations' External Active Thermal Control System.  The tests were
conducted at the JSC Thermal Test Bed facility in February.  The
knowledge-based system's intelligent display, provided improved
monitoring and fault management capabilities to the thermal control
system automation project team.  The magnitude of data being monitored
by personnel during the tests is similar to that which will be monitored
by the station's flight controllers.  During the tests, the knowledge-
based system diagnosed real hardware problems and alerted the test
operators.
        Advanced automation and the approach being taken by this project
yield several benefits to the Space Station Freedom program.  The
thermal control system automation project schedule will enable advanced
automation to play a ground-based support role by the station's first
element launch (the first in the series of Space Shuttle flights to
assemble the station).  Reliability and functionality will be improved
by using automated techniques to monitor data, identify unexpected
faults and predict when corrective or preventive maintenance should be
performed.


SCIENCE TEACHERS ABSORB STATION LITERATURE

        Enough teachers to form a small town descended on Boston in March
for the 40th annual National Science Teachers Association conference.
        The number of science teachers who showed up for the four-day
conference and exhibition far exceeded the 17,000 who preregistered.
        By Saturday, about 21,000 teachers were attending seminars and
milling through two floors of corporate and government exhibits.
        For the first time since the program's inception, Space Station
Freedom had a booth staffed with program personnel and support
contractors.  The booth debuted and distributed a fistful of education-
oriented Space Station Freedom material to about 6,000 people.
        The following materials were handed out:
        *       Hey, What's Space Station Freedom?, a 30-minute video
divided into three segments -- a teacher describing how space can relate
to the classroom, an astronaut describing space station features to a
group of children, and an animated dream sequence where the children are
on a 90-day mission aboard Space Station Freedom;
        *       A series of four education-oriented artist concept
lithographs explaining the uses, benefits and research that will be done
aboard the space-based laboratory;
        *       The Great Nations Dare to Explore slide show, with script,
describing the program, its purpose and benefits;
        *       Two separate fact sheets ?? one for children and one for
adults;
        *       An artist concept lithograph/fact sheet by Grumman
Corporation;
        *       Station Break; and
        *       A limited supply of Freedom patches and posters.
        Although still under production, the booth also featured a set of
three guidebooks -- elementary, middle school and high school levels --
that demonstrate how space exploration can cut across all curricula --
from social studies to physics.  About 300 teachers registered to
critique the guidebooks' usefulness.  Space Station Freedom's
Spacelab/Space Station Utilization program is working hard to have this
product available for the cost of reproduction by late fall. When
complete, these guidebooks will be available for purchase at the
regional NASA teacher resource centers.
        Some of the products listed above, the video, lithographs and
slide show should be available at the resource centers.


POTENTIAL STATION USERS TO MEET IN ALABAMA IN AUGUST

        Potential users and researchers of Space Station Freedom will meet
at a conference in  Alabama in August.
        The first Space Station Freedom Utilization Conference will be
August 4-6 at the Von Braun Civic Center in Huntsville, Ala.  The
conference will include a payload data services workshop, which will be
held at the nearby Hilton Hotel.
        The conference is open to anyone seeking information about
Freedom's research capabilities and researcher plans.  Speakers will
come from the government, industry and academia.
        The federal government fee is $70, others must pay $150 until June
19 and $200 after that date. The data services workshop fee for
government employees is $60, others must pay $110 until June 19 and $160
afterward.  For information call Eula Hume, BDM, [phone].
        Potential space station users will be researchers and scientists
from universities, industry, government and other institutions
interested in conducting space research in basic and applied science,
technology development and commercial activities.
        Science users will study the fundamental theories of fluid
behavior, solar system formation, meteorology, and the effects of low
gravity on humans, animals, plants and materials. Such an approach
ensures maximum scientific return from planned investigations and it is
expected to identify new techniques and processes for commercial use to
U.S. ground-based industry.
        Technology development users will examine structures, space
environmental effects, noise and vibration, energy systems, propulsion,
integrated circuits, automation and robotics and life support systems.
These technologies will nurture innovation in Earth-based industries and
future space missions.
        Commercial users will perform research with valuable applications
in the medical, agricultural and chemical, purification and recycling
systems, and food production industries for both Earth and space users.
        The utilization plans being developed by NASA will ensure that
Freedom's research capabilities are used efficiently and effectively.
From the beginning, Space Station Freedom has been designed to
accommodate user requirements.  The unprecedented research resources
available at permanently manned capability include:
        *       44 experiment racks the size of a large refrigerator;
        *       30 kilowatts of electric power;
        *       4 crewmembers, with two devoted to full time research;
        *       Data transmission rates of 50 megabits per second;
        *       High-speed computers with fiber optic communications links;
        *       Long duration missions; and
        *       Externally mounted experiments with power and
communications.
        Greatly enhancing overall space station utility is the modular
design of the experiment racks. The modular rack design eases removal
and replacement , as necessary, with other racks containing different
experiment equipment.  When a payload's "tour of duty" is complete, it
will be removed from the laboratory and returned to Earth, where its
sponsor will analyze the results.  Payloads will continually cycle into
and out of the space station on a regular schedule, just as ground-based
research is scheduled in laboratories on Earth.  This flexible
capability ensures that Space Station Freedom will remain at the leading
edge of space-based research for decades to come.
        Another asset for space station users will be the 2.5-meter
variable-gravity centrifuge which will permit research on plants and
small animals through controlled exposures to varying gravity levels.
The centrifuge will be the single most important research tool for space
life sciences and its deployment will mark the beginning of full-scale
biological research in space.


TRUSS SPACE ALLOCATED FOR ATTACHED PAYLOADS

        Space Station Freedom will provide accommodations for payloads to
be attached to the truss assembly.  Two locations will be provided at
man-tended capability (MTC) scheduled for Spring 1997 increasing to four
locations a few months later.
        The attached payloads will be able to face upward (zenith), Earth
(nadir), forward of the space station (ram) or behind the space station
(wake).  Each attached payload site will have a mechanical attachment
capability for a single attached payload or a carrier of multiple
attached payloads.  Each site can accommodate a payload mass of at least
5,000 pounds, and provide a clearance envelope of at least 1,000 cubic
feet.
        Power and data transmission ports will be provided to the sites.
Each port will be capable of providing at least 3 kW peak power (120
Vdc) with 500 W of survival power. A maximum of 6 kW total power is
available.  A data transmission capability of 400 kbps downlink to Earth
will be available at each port.  An aggregate transmission rate of 20
kbps will be available for uplink.  Thermal control will be passive.


HOUSE AUTHORIZATION COMMITTEE MARKS UP SPACE STATION BUDGET

        The House Authorization Committee last month marked up Space
Station Freedom's fiscal year 1993 budget, authorizing a fully-funded
three-year budget cycle for the program.
        This, however, is only the first step in a long budget process.
The authorizing committee sets the limits any one program can spend.
Actual funds are doled out by the appropriations committee.
        President Bush requested, and the committee authorized, full-
funding for Space Station Freedom at $2.25 billion for fiscal year 1993.
The administration, at congressional direction, requested flat funding
at $2.25 billion for the program from fiscal years 1993-1995.
        Underscoring their support for the program, the authorizing
committee recommended increasing the budget $2.4 million above the
president's request of $2.25 billion in 1994 to $2.4 billion, and $4.9
million above Bush's $2.25 billion request in 1994 to $2.74 billion.
        Of the $2.49 billion authorized for budget year 1994, $1 million
of the that must be used for an assured crew return vehicle, also known
as Space Station Freedom's 'life boat'.  The assured crew return vehicle
is essential for astronauts to work and live aboard Freedom permanently.
The million dollars also must be used to work toward boosting Freedom's
power level from 56 kW to 75 kW, as well as work toward increasing the
number of crewmembers from four to eight.  Two million of the $2.74
billion authorized for fiscal year 1995 must be used to further these
goals.
        In its report language, the committee said, it "is encouraged that
the restructured Space Station Freedom program has achieved an increased
level of programmatic stability over the past year and that technical
progress has been made."


NEWS BRIEFS

*       Dr. William B. Lenoir resigned earlier this month as NASA's
associate administrator for the Office of Space Flight.

        During Lenoir's tenure as associate administrator for space
flight, NASA completed a major restructuring of the Space Station
Freedom program, reducing its development costs by $6 billion,
simplifying its subsystems and improving its assembly process.


*       The McDonnell Douglas Avionics Design and Installation (AD&I)
Lighting Systems Group "shed some light" on its pre-integrated truss
mock-up as they performed the lighting test.

        The nighttime test led by AD&I teammates Jennifer Barton, Roy
Lothringer and Clare Rezner wass conducted to find out how much light is
needed for space walk operations, such as  outside maintenance.

        The valuable data collected during this test will be used to
verify the translation lighting methods, determine the minimum lighting
levels needed for space walk activities and determine how the portable
light should be attached to the translation cart.