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Station Break - March 1992
IML Spacelab Mission Yields "Awesome" Science Results
Payload scientists of the first International Microgravity
Laboratory will spend the next several months analyzing
experiments that flew aboard what Mission Manager Robert
McBrayer described as an "awesome" Spacelab mission last
month.
"It's great to see a good plan come together," McBrayer
said.
"Everything went quite well," said Mission Specialist
Robert Snyder. "Everyone is pleased."
The mission work is highly representative and is
considered precursor work to the kind of research that will be
done aboard Space Station Freedom beginning in late 1996.
This eight-day mission, which brought nearly flawless
science results, is less than 25 percent of the number of days
Freedom's man-tended capability will achieve per year.
Managers expect to make three 13-day or longer missions
each year through late 1999, when, on a rotating schedule,
Freedom crews will live and work continuously.
Some results of the fifth science mission using the
European Space Agency's facility aboard Spacelab are:
? Science teams for the four Critical Point Facility
experiments saw never-seen phenomena as they monitored
fluids at the critical temperature where liquid and vapor
phases become indistinguishable.
? Eleven runs of the casting and solidification
experiment, completed mid-mission in the Fluids Experiment
System, were flawless. After the payload scientists complete
analysis of nearly 300 three-dimensional holograms, the
University of Tennessee Space Institute experiment scientists
plan to make their results available to technology developers
of sophisticated alloys.
? Canada's Space Physiology Experiments team
completed all of its scheduled test runs, as well as some extra
stereo photography in the study of back pain in astronauts.
President George Bush Declares 1992 International Space
Year
Editor's Note: This is an excerpt of President Bush's speech
to the Young Astronaut's Council last month.
I'm so glad to see so many boys and girls here from
kindergarten through ninth
grade in this Young Astronauts program. As President, I've set
a goal that involves you young people, and my goal is for
young Americans like you, who are in grade school right now,
to travel to Mars some day. New travels in space will give us
answers to some of the things that children wonder about. And
I might add, many adults who contemplate our great universe
wonder about these things, too.
The other day I heard what one 5-year-old wonders
about. One of my staff members asked his 5-year-old kid if we
should build new space ships and send people to the Moon
again. And the kid said, yes, of course, we should, and his
father said, well, why. Why should we send them to the
Moon? That's easy, the kid said. It's to see if there are any
Martians there.
Well, we can chuckle about that, but the kid got it about
right. As most of you Young Astronauts know, we've
challenged America to go back to the Moon to stay and then
onward to Mars. And sending people back to the Moon for
more experience in an environment different from ours is the
first step on the journey to explore the gigantic rifts, valleys
and mountains of Mars.
When we break through barriers of the unknown, we not
only help ourselves, we learn a lot more about ourselves. And
when we reach our goal of sending men and women to Mars,
we can find out the answer to that little 5- year-old's wondering
about life on other planets. We can learn whether we can
extract air and water from materials on Mars to sustain life.
We can look for clues on Mars, not only to teach us how the
Earth developed, but also about the wellspring of life itself.
And pushing forward into space already is helping us
here and now. More and more, the new jobs for people of your
parents' generation are being provided by our space
programs. Revenues from American commercial space
programs alone grew by 14 percent in 1991 and this year
they're projected to grow by 20 percent. The commercial
space business has grown so far and so fast that it now takes
in about as much money each year as all the receipts at the
movie theaters all over the United States.
. . . America now exports one billion?one billion dollars
a year in commercial space goods and services. Those
exports alone translate into jobs for 20,000 Americans. Real
progress is happening almost faster than we can imagine.
Navigation satellites that helped guide our troops in Desert
Storm just a year ago now help hikers and fishermen and
surveyors and motorists find their way.
. . . Space exploration should be and will be a national
effort and I should again state that Dan Quayle's leadership is
invaluable as to the renewed focus and momentum of our
space programs. When I send my annual budget up to
Congress next week, it is going to mark the third straight year
that I've called for a real increase in spending on our civil
space program. And this includes full funding for Space
Station Freedom.
Space station is back on track and on schedule. Last
year we had an honest debate with those in Congress who
wanted to kill Space station. We won, because the American
people agree that space Station Freedom is not only a very
valuable scientific program but it is essential to our destiny as
a pioneering nation, a pioneering nation in space. I know
many are concerned about the balance between science and
exploration in our space program, and the budget that I will
propose next week will not shortchange science. Space
science will remain more than 23 percent of NASA's program
and will increase by 10 percent over the current year.
But America's destiny must include manned
exploration, so my budget increases funding for technologies
we need to send man beyond Earth's orbit, and that includes
propulsion technologies, life support technologies, and two
new missions to complete the mapping of the Moon.
. . . For you to fulfill your dreams of space exploration
when you become adults, we must make a new public
investment in our space program now. And I'm asking
Americans to make a farsighted commitment, one that looks
dozens of years and millions of miles beyond the recession
and the other things that tend to preoccupy us today.
And I'm challenging you young people, too. Start your
preparations for tomorrow's new age of space exploration now.
. .
Aldrich Addresses Accomplishments, Challenges
Editor's Note: This is a Station Break interview with Office of
Space Systems Development Associate Administrator Arnold
Aldrich.
Q: What is the purpose of the Space Station Freedom
Program?
A: Space Station Freedom will be a permanent outpost
where we will learn to live and work productively in space. It
will serve as an advanced research facility where people from
many countries and scientific disciplines will utilize its unique
resources to conduct a wide range of scientific and
technological studies to further our understanding of space
and to benefit life here on Earth. Freedom will also provide us
with the experience and knowledge of building, operating and
maintaining large systems in space. In the long run, Space
Station Freedom will become an integral part of our space
infrastructure, providing benefits we can't imagine today.
Q: Is the Space Station Freedom Program in good shape
today technically? Financially?
A: I'm delighted to be able to say that the Space Station
Freedom Program is in better shape today than it has ever
been. We are now only 44 months away from our first
assembly mission, we've completed a comprehensive design
review with relatively few changes necessary, we're on
schedule, and we're right on track with our cost projections. I
believe this is testimony to the outstanding contributions of
everyone involved with the space station program including
the NASA and contractor managers and every other person
involved with space station development. They have all done
a terrific job of addressing the numerous challenges posed by
this program over the last couple of years.
Q: What challenges does the program still face
technically? Financially?
A: While our past accomplishments are numerous, we are
not resting on our laurels. We have a number of key
milestones ahead of us before we see the first components of
Space Station Freedom being hoisted out of the Space Shuttle
cargo bay. Our primary ongoing challenge is keeping the
design progress moving ahead while maintaining cost and
schedule targets. That is always a major challenge in a
project of this magnitude. Technically, we are now gearing up
for our man-tended phase critical design review which will
culminate a year from now in the spring of 1993. At that point,
our designs for the man-tended phase of the program will be
90 percent complete and construction of flight hardware will be
well underway. We are also closely watching extra-vehicular
activity, weight and power requirements which have a natural
tendency to creep up.
Another challenge we face is to continue to improve
our understanding of the micro meteoroid and orbital debris
environment in which Freedom will operate. However, we
believe the space station design appropriately addresses this
environment. Also, our plans and procedures for space station
component, element and stage verification prior to launch will
require an intensive effort in the coming months. Designing,
building and incrementally verifying a system as large and
complex as Space Station Freedom is a significant technical
and management challenge. And assembling these
components and ensuring that they function perfectly after
launch and after months and years of operation in space is a
challenge on a magnitude never before attempted. But, I'm
confident we're up to these tasks. NASA's history is full of
examples of success in activities of similar magnitude. So
there's a lot of work to be done, but as I think our track record
shows, we are up to and looking forward to the challenges
ahead.
Q: What were the 1991 accomplishments?
A: Well, as you know, 1991 was a big year for progress.
On the heels of completing the program preliminary design
review in December of 1990, we initiated a major restructuring
of the program to meet new congressional cost and functional
guidelines. In March, we completed this activity, successfully
meeting the recommendations of the "Augustine Committee"
and the guidelines from Congress, while maintaining a world-
class research facility. This was no easy task. We also
completed a lot of hardware testing during this past year,
leading to the man-tended capability preliminary design review
which was completed in December 1991. This review
validated the bulk of our designs up to that time and gave us
new insight and direction in the few areas where additional
work was needed.
I also must add that one of our most significant
accomplishments last year was receiving full funding for the
program for fiscal year 1992. We are fortunate to be able to
count a number of visionary members of Congress and of the
congressional staff as among our strongest proponents. They
deserve a lot of credit for their contributions to this program.
Q: What are the program's 1992 goals?
A: During 1992, we intend to move a long way toward
preparing for that first launch. We will concentrate on the
incremental critical design reviews which lead to the man-
tended phase critical design review in the spring of 1993. This
will require an intensive effort within all of the work packages.
Firm progress leading up to the critical design reviews and
efficient completion of these activities will be required to
support flight hardware deliveries to the Kennedy Space
Center 26 months later. Another major effort this year will be
to develop our plans for final system verification of all space
station components. By the end of this year, we plan to be
close to full definition and implementation of these
requirements.
Q: When will the first flight hardware be delivered to
Kennedy Space Center (KSC)?
A: Based upon our current schedule, we will deliver the
first full solar array of the electrical power system to KSC in
July of 1995.
Q: Will the program maintain schedule and budget? How?
A: Of course, this is partially dependent on the support we
continue to receive from Congress, but with continued
vigilance on the part of the station contractor and government
management team, I fully expect that we will stay on schedule
and on budget.
Q: What is your response to naysayers from the science
community and at large?
A: Our country's greatness is built on openness and
freedom of opinion. The space program is no different and we
welcome constructive inputs. Unfortunately, as the federal
government's supply of resources has failed to keep pace with
the evolution of good ideas for investment, some have been
led to believe that Freedom is a threat to funding in other areas
of science. I would point out that the growth in the NASA
science budget has more than kept pace with that of Space
Station Freedom. The science budget remains at or above its
traditional level of 20 percent of the NASA budget ? a level
most recently endorsed by the "Augustine Committee. "
I firmly believe that if the space station program
were cut today, the resources thus made available would be
distributed to other needs and science would receive very
little, if any, additional funding. Overall, science would be a
major loser in such an adjustment as the unique opportunities
for research that space station promises would be lost or
deferred. We are working very closely with many individuals
in the science community and there is a great deal of support
for the space station program. Our joint planning will ensure
that once fully operational, Space Station Freedom will provide
far more extensive research capabilities than any other facility
ever operated in space. While I appreciate the concerns that
some researchers have expressed in the past, I believe that
the investment we make today in Space Station Freedom will
prove to be an extremely wise one in terms of the return to our
nation in the form of knowledge, experience, opportunities and
inspiration.
Q: What is the station's role in exploration?
A: Before humans travel to another planet, we must
dramatically improve our understanding of the reactions and
changes to the human body when exposed for long periods of
time to the environment of space. Space Station Freedom is
our primary means for supporting this research. Also, Space
Station Freedom will provide us with real experience in
building and operating very complex life support systems in
space. This knowledge is crucial for our planning to send
humans beyond the Earth/Moon system.
Q: How will Space Station Freedom benefit this nation and
the world? Future generations?
A: First, our nation will benefit from new scientific and
technical knowledge in many disciplines which will apply
directly to improving our life here on Earth and to enhancing
our international competitiveness. Perhaps as important,
however, is that Space Station Freedom will continue the
United States' leadership in space. Freedom is the next
important step toward evolving mankind's capabilities to live
and work in space and to explore and benefit from this new
frontier.
The world will benefit from Space Station Freedom
through its demonstration that competing nations can come
together in cooperative efforts to advance mutual interests.
Freedom is by no means just a U.S. program, and our
international partners bring significant additional scope,
capabilities, resources and commitment to the program. An
international space venture such as this sets an important
precedent in the utilization and settlement of space ? peaceful
and productive cooperation. I believe we cannot afford to let
this opportunity slip by us.
In the decades ahead, we will continue our vigorous
scientific investigations of the universe and mankind will
follow its destiny to proceed outward into the solar system.
Along the way, new and as yet unimagined technologies will
evolve from our space program to provide many benefits to life
here on Earth. Space Station Freedom is the next vital link in
this evolutionary progression.
Q: Do you feel the American people support this program?
A: The American people have always supported a strong
space program. Our successes have made us the envy of the
world and improved our lives in many ways. It is appropriate,
as the nation experiences tough economic times, to reevaluate
our national priorities. I believe that as this debate continues,
the nation will continue to conclude that Space Station
Freedom and many of our other space activities are strong and
necessary investments in our nation's future.
Q: How will management changes at Headquarters and
the centers affect the program?
A: In the near term, the Space Station Freedom
management structure will change very little. I well recognize
the stability the program has had over the last 18 months and
the progress the current management team has achieved. In
the longer term, our management structure will adapt to the
needs of the program as it matures. In very general terms, I
anticipate that the level one and level two portions of the
program will tend to consolidate downstream of the critical
design review, while the activities at the centers related to
hardware verification and operations will grow. It is
envisioned that the Johnson Space Center will be the center of
focus for the man-tended phase of the program and the
Marshall Space Flight Center will be the center of focus for the
permanently-manned phase. In response to the NASA "Roles
and Missions" strategy, I am working with the various levels of
space station management and the NASA center directors to
develop a space station management evolution plan by the
end of 1992. I expect downstream changes resulting from this
plan will be gradual in nature and will be implemented with the
intent of minimizing their impact on program activities and the
individuals involved.
Q: Do you think the American people understand this
program?
A: I think if there is one area where we have not done as
much as we could, it's in explaining in clear terms the
tremendous value of this program. We may have taken for
granted the public's understanding of this program, and not
given education enough attention. I have resolved to change
this and to dramatically improve our education efforts.
Japanese Software Support System Begins Operation
The Japanese Experiment Module (JEM) Software
Support Environment System (J-SSE) is used to develop and
control software for the computer installed aboard JEM the
Japanese contribution to Space Station Freedom.
Because astronauts will fly aboard JEM, higher safety
and reliability are required for the software. In addition, as
onboard equipment and experiment missions are replaced and
revised during the JEM 30-year operation period, it will be
necessary to maintain and revise JEM's software easily. The
J-SSE contains rules about development and control of the
software onboard JEM necessary for realizing required safety,
reliability and maintainability. A computer system is also
provided to develop and control software according to the
rules. Software developers can accomplish these
requirements effectively utilizing the J-SSE.
The next cadre of rules to be set up are software
requirement analysis, design techniques, programming
language, program description style and testing techniques,
as well as techniques for schedule and progress control,
configuration and quality control.
For the computer system, a total of 68 work stations
will be laid out and then distributed into four subsystems
according to applications. A large computer will be used as
the technical information control system. The system will be
constructed to facilitate liaison and data exchange between
developers.
Software designed to develop programs for software
requirement analysis, design tool, compiler and test
achievement measuring tool, etc., will be installed in the work
stations. Software for software control will be installed in the
large computer.
? Article Courtesy of NASDA
Space Station Utilization and DMS Conference to Meet in
Huntsville
The first Space Station Freedom Utilization Conference
will be held in early August at the Werner von Braun Civic
Center in Huntsville, Ala. Potential users will be briefed on the
program's status, station research capabilities, procedures for
getting payloads onboard, and general policies and plans.
They also can present their own utilization plans, interact with
other users, and exchange ideas.
The Space Station Freedom Utilization Conference will
include a Payload Data Management System (DMS) Workshop,
which also will be held in early August in Huntsville. The
workshop will develop a working relationship between data
management system designers and payload developers who
will use data management services onboard Freedom.
Participants in both the Utilization Conference and the DMS
Workshop will have an opportunity to meet throughout the
week at the civic center exhibit hall and at a reception at the
U.S. Space and Rocket Center. They also will be able to visit
the Space Station Freedom mock-up at Marshall Space Flight
Center.
Registration forms will be sent in early March. If you
do not receive one by mid-March and would like one, call Eula
Hume at (202)479-5242 or fax your name and address to
(202)479-5269 stating you're interest in the conference or the
workshop.
Digraphs: Advanced Automation to Assist Designers,
Operators
A Space Station Freedom mission controller is
monitoring one of the many systems that comprise the
international space station. The routine of the shift is
suddenly snapped into sharp focus by the occurrence of a
fault, indicated by simultaneous onboard and ground detected
caution alarms.
The controller enters the caution and warning
information into a computer program that models the Station's
failure environment. The computer quickly determines nearly
a dozen possible causes for the anomalous condition and
displays their locations to the controller on a schematic of the
Station's systems. Most of the potential causes are quickly
dismissed by the controller due to a lack of corroborative
indicators. For the few remaining possibilities, the other
controllers are quickly polled on the status of their systems.
Within moments it is determined that a component in the
power system has begun to fail, causing caution alarms to
activate in the other systems. Systems are returned to normal
status and a log entry registers a new maintenance action for
the crew.
The scenario exemplifies the demanding requirements
and stressful situations that complex systems can impose on
individuals. It also demonstrates the potential of automation
tools to help meet this challenge. The complexities of space
systems are such that analysis of individual subsystems is
not adequate to understanding the operation and performance
of the system as a whole. Teams of engineers, each expert in
the design of specific subsystems, must work together to
identify and understand issues dealing with the overall
operation and performance of the system.
However, the system understanding created by the
combined knowledge of a group working together is difficult to
capture and retain. It would be a significant accomplishment to
develop a procedure or tool that captures this level of system
understanding. One promising approach when assessing a
system's susceptibility to failures has been to capture system
design knowledge with a technique called "digraph analysis."
The digraph, or "directed graph," technique was
developed and used at Lawrence Livermore National
Laboratory for analyzing the vulnerability of nuclear systems
to component failures. Its use has since been expanded to
include Department of Defense and NASA applications. NASA
was introduced to the technique in 1986 during the post-
Challenger search for a means to capture knowledge and to
assess risk. The system knowledge captured in digraph form
offered a means to differentiate the relative importance of the
thousands of critical component failures on the Shuttle. Since
then, digraphs have been used to model several Shuttle and
Space Station Freedom subsystems, functions and
experiments.
NASA initiated the development of the Failure
Environment Analysis Tool (FEAT), which uses the digraph
technique to analyze the propagation of failures in a system or
across systems. Initial work was sponsored by the Propulsion
and Power Division at the Lyndon B. Johnson Space Center
(JSC). The current enhancement effort is being led by the JSC
Automation and Robotics Division, with support from the Space
Station Level I Engineering Prototype Development activity,
the Level II System Assessment Office, and the station's
Technical Management Information System (TMIS)
organization.
This failure analysis tool efficiently captures the type of
design information, which always must be developed by
subsystem and system engineers. A digraph model is a
representation of the logical connections between events in a
system, showing how failure effects propagate within or
between systems. Working from the schematic diagram of a
system, the digraph models are developed and processed
through FEAT. The principal capability of FEAT allows users to
ask two types of questions about the system:
(1) What happens if this (or these) failure(s) occur(s)?
(2) What can cause this (or these) condition(s) to
occur?
Systems may be modeled to different levels of detail
for a variety of purposes. Once the individual subsystem and
system experts have agreed that the model accurately
represents the propagation of effects within the system, a
single person can use that model to quickly assess real or
potential problems. No longer is it necessary to bring a group
of experts together to answer those questions, even when
propagation paths cross system boundaries. Engineers and
subsystem managers can then use the failure analysis tool to
demonstrate the response of the modeled system, or systems,
to various failures. A simple example showing a schematic
and its digraph equivalent is presented in Figure 1. It
represents a mechanical pump with two power supplies. The
events that can cause the pump to fail are either a mechanical
failure of the pump itself, or a failure of both power supplies.
The digraph can be expanded to model the pump and its power
supplies in more detail. It also can be part of a larger digraph
of a complete system model.
Digraphs can be useful and instructive in all program
phases. During development, digraphs help engineers
understand the strengths and weaknesses of the overall
design. In the operational phase, these models can be used
by mission controllers to quickly identify and display the
possible causes of malfunctions. Mission controllers can use
FEAT in the Space Station Control Center to monitor operations
over the station's entire life. As a training tool, operators can
quickly learn the capabilities and vulnerabilities of a system.
They will be using digraphs in the failure analysis tool, with
accompanying schematic drawings and data base information,
to speed up and simplify their learning process.
As models mature and come under configuration
control, they continue to be of use for training, operations,
design modification and decision support. Moreover, the use
of the failure analysis tool allows engineers to design and
analyze systems from within a common modeling framework.
This provides a consistency to the design process
among the engineers and across systems which improves
communication and confidence in design reviews, and in
system verification and integration.
The failure analysis tool provides NASA's engineers a
tool that improves the safety and reliability of system designs.
Use of digraphs to model various flight and ground systems is
expanding within the Space Station Freedom Program. For
further information about FEAT or digraphs, contact: Ginger
Pack at Johnson Space Center (713)483-1515, or Mark Gersh at
NASA Headquarters (202)453-1895.
News Briefs
NASA Administrator Richard H. Truly last month
announced his resignation effective April 1. At presstime, no
one has been named to replace Truly.
Truly's resignation ends nearly 37 years of continuous
military and government service. Truly, a retired vice admiral
and astronaut, was hand picked to lead the Office of Space
Flight after the 1986 Challenger accident. He was appointed
NASA administrator in 1989.
"I have watched the talented men and women of this
elite agency turn heartbreak and disarray into the impressive
achievements and superb organization of today," Truly said in
his resignation letter.
"With 20 safe and successful Shuttle flights in the last
40 months, scientific discoveries pouring in, Space Station
Freedom on track, and our wind tunnels testing the airframes
and spacecraft of tomorrow, they deserve to be very, very
proud," Truly said.