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April 1991 "Station Break" Space Station Freedom Newsletter

  Congress Approves Modified Space Station

New Design Features shorter, pre-integrated truss and modules

        NASA delivered the "restructuring" report to the Congress,
outlining an extensive redesign of the Freedom space station.  The
new design is cheaper, smaller, easier to assemble in orbit and will
require fewer Shuttle flights to build.

        Major new features of the redesigned space station --
shorter U.S. laboratory and habitat modules that can be outfitted
and verified on the ground and a pre-integrated truss that can be
assembled on the ground and tested with all of its subsystems intact
-- will significantly reduce intravehicular activity (IVA) and
on-orbit extravehicular activity (EVA) needed to build and maintain
Freedom.

        "We've come out of this with a space station we can be proud
of, a space station we can do.  We know we can do it.  We now need
stability in funding to turn it into reality," Dr. William B.
Lenoir, associate administrator for space flight said at a press
conference last month.

     "This new design for Space Station Freedom accomplishes every
major goal we set for ourselves when we kicked off this effort last
November," Lenoir said. "We took the directions from Congress and
the Augustine Commission recommendations to heart, and the program
we are announcing today addresses each and every one of their
requirements.

     "We've cut costs, simplified the design and reduced the
complexity of the project.  At the same time, Freedom will be a
quality facility, providing a research laboratory unsurpassed in the
world for life sciences and microgravity research, and a stepping
stone into the future, enabling NASA to conduct the research and
planning necessary for human exploration of the solar system.  And,
we have maintained our international commitments," he continued.

        A 1991 fiscal year budget shortfall of more than $550
million, along with Congressional directions to significantly reduce
out-year spending, prompted NASA to begin the restructuring of
Freedom. Congress told NASA to expect no more than 8 to 10 percent
growth over the next 5 years (fiscal year 1992-1996), with peak
spending for Freedom not to exceed $2.5-2.6 billion.  The budgetary
ground rules, including the cut for fiscal year 1991, represent a
$5.7 billion shortfall from what NASA had planned to spend for
Freedom over that same time period.

        NASA directed the review in November 1990 with instructions
to the Freedom project team to: develop a phased approach with
quasi-independent phases; protect life and materials science;
maintain international agreements and capability; limit assembly
flights to no more than four annually; and achieve first element
launch, man-tended capability and permanently manned capability as
early as possible.  The restructured program calls for the first
element launch of the space station to be made in the second quarter
of fiscal year 1996 (January - March 1996), and man-tended
capability to be achieved in the third quarter of fiscal year 1997
(April-June 1997).

        In the man-tended phase, astronauts brought up to Freedom by
the Space Shuttle will be able to work inside the U.S. laboratory
for periods of 2 weeks.  They will return to Earth with the Shuttle.
At this stage, one set of Freedom's solar arrays will generate about
22 kW of power with a minimum of 11 kW available to users.  Six
Shuttle flights will be required to achieve the man-tended
configuration.

        Freedom will achieve a permanently manned configuration in
fiscal year 2000.  This configuration will consist of the U.S.
laboratory and habitat, as well as the Eu-ropean and Japanese
laboratories; the Canadian Mobile Servicing System; accommodations
for a live-in crew of four; and three sets of solar arrays
furnishing 65 kW of electrical power, with a minimum of 30 kW going
to the users and the remainder to housekeeping chores.

        A new requirement before permanently occupying the station
will be the availability of an Assured Crew Return Vehicle to return
space station crew members to the Earth in an emergency.  Seventeen
Shuttle flights will be needed to build the permanently manned
configuration.

        Provisions to expand the space station have been maintained.
The follow-on phase of the Freedom program will include another
solar array to achieve 75 kW, provisions for 4 additional crew
members and could include additional capabilities such as a second
pre-integrated laboratory and additional nodes.

         This phase would use the new launch system for launch and
assembly if the launch system is available.The redesigned U.S. lab
and hab modules are 27 feet long and 14.5 feet in diameter, about 40
percent shorter than the previous design.  The smaller size allows
the modules to be fully outfitted and tested on the ground prior to
being launched into orbit.  The U.S. lab module will hold a total of
24 8-foot wide racks, 15 of which initially are devoted to
scientific work.  At permanently manned capability, 28 experiment
racks will be available to U.S. investigators: 12 in the U.S. lab,
11 in the ESA lab and 5 in the Japanese lab.

        The redesigned truss segments will be built, preassembled
and checked out on the ground.  Form-erly, the truss was to have
been assembled, like a massive erector set, by astronauts performing
space walks.  NASA estimates the pre-integrated truss will cut
assembly EVA by more than 50 percent.

        While work on the Attached Payload Accommodations Equipment
(APAE) suitable for large external payloads has been stopped,
utility ports for small external payloads will be placed along the
truss.

        The overall width of the station has been reduced from 493
feet to 353 feet.

        Complexity of other station systems also has been reduced
and where possible, hardware already flying on the Space Shuttle
will be used in place of developing new hardware for the station.
Also called for in the plan is the transfer of the Flight
Telerobotic Servicer to NASA's Office of Aeronautics, Exploration
and Technology. This, together with the deferral of the APAE, has
eliminated the Goddard Space Flight Center's Work Package 3 from the
Freedom program.

        In addition to changes to the flight hardware, a number of
changes to ground facilities are planned.  The Space Station
Processing Facility to be built at the Kennedy Space Center will not
be fully outfitted, and a new hazardous processing facility has been
deleted in favor of using an existing facility.  The size of planned
facili-ties at the Johnson Space Center -- the control center and
crew training facilities - have been scaled back.  Payload
facilities at Marshall Space Flight Center are being deferred and
existing facilities will be used in the interim.

        Due to funding cutbacks and hardware changes in the program,
some layoffs of prime and subcontractor personal have already taken
place, and more are expected.  At Work Package 1, no layoffs at the
prime contractor, Boeing, are expected, but more than 500 people
will be reduced from the subcontractor roles, some of which will be
accommodated through transfers and attrition.

        At Work Package 2, prime contractor McDonnell Douglas has
already reduced its work force by about 160, with half that number
being layoffs.  Major subcontractors to McDonnell Douglas will be
reduced by about 470, with layoffs accounting for approximately half
of that, and another 200 will be reduced from supporting
development, with about 65 of that total coming from terminations.
At Work Package 4, no layoffs are expected, but as many as 40 people
in support jobs at Lewis Research Center will be reassigned.
Layoffs of about 30 percent of the work force at the Space Station
Engineering and Integration Contractor, Grumman, were announced
earlier this month.

  SSAC to Oversee Restructured Station


        After preliminary approval of a newly modified Space Station
Freedom, the Space Station Advisory Committee (SSAC) last month
accepted an armload of challenges from Office of Space Flight
Associate Administrator Dr. William B. Lenoir to keep the program
alert to potential problems.

        Lenoir asked committee members to continue to monitor:

* the station's data management system and recommend ways to avoid
     possible glitches in the system;

* system-level verification plans;

* external and internal maintenance;

* utilization flights;

* induced environment, including microgravity;

* assured crew return vehicle requirements and development and
      plans.

        Lauding the committee's past efforts to keep the program on
its toes, Lenoir said, "NASA needs your assistance and expertise to
help us know when we need to do things differently."

        The next SSAC meeting is slated for June.

        During two all-day meetings, the advisory committee was
briefed by Space Station Freedom Director Richard Kohrs on the
five-month-long restructure assessment study; Space Station Chief
Scientist Dr. William Taylor on user accommodations; SSAC member Dr.
Robert Bayuzick on how the Space Station Science and Applications
Advisory Subcommittee reacted to restructuring (see story, page 3);
SSAC member Dr. William C. Schneider on the Aerospace Medical
Advisory Committee restructuring concerns, and; SSAC member John
Miller on the status of the data management system.

        Kohrs told the committee that the program continues to work
to ensure minimal impacts to the station users of power, rack space,
crew availability, and data rates, etc.  Kohrs also said, while the
program will not preclude future long-term growth, it cannot afford
to accommodate all of those requirements at this time.

        Despite some remaining concerns that continue to be worked,
Taylor told committee members that the restructure assessment helped
push improvements in several areas, such as microgravity, power, and
rack availability.

        Taylor said that 20 percent of the U.S. laboratory would be
within 1x10-6g, and 100 percent will be within 3x10-6g.  In fact,
Kohrs said, those numbers continue to improve.  Taylor also said
that NASA plans to provide an acceleration mapping system in the
U.S. lab.

        Until permanently-manned capability in late 1999, Freedom
will be maintained at 10.2 psia to reduce pre-breathe time for
external maintenance activities.  Some time later, after assembly,
the station pressure will be increased to 14.7, Taylor said.

        Concerning the data management system, Miller pointed out a
list of potential problems, and told Kohrs the program must address
these to avoid future headaches.

        One of Miller's main concerns was the possible
incompatibility of software because several different companies are
developing programs for the station and its ground-support
facilities.

        Other concerns include:

* commercial off-the-shelf software upgrades provided to NASA may
     not have been validated by the manufacturers and thus could
     cause problems;

* the probable cost of the necessary data management system kits is
     too high for the payload developers;

* top-level requirements do not always appear in the design, and;

* validation and verification of the hardware and software is
     needed, including analytical modeling, simulation under
     emergency conditions, prototype testing and validation, and
     multiple fault analysis of hardware will be difficult.



After Restructure Exercise, Station's Lab Remains Top-Notch
Facility, PhDs Say

     When Space Station Freedom's budget had $550 million cut from
its 1991 budget request of $2.45 billion to $1.9 billion and was
ordered by Congress to reassess the station's design, many potential
science users expected the worst.


        The worst did not happen, however, and the users can now
breathe a sigh of relief, said Dr. William Taylor, Space Station
Freedom chief scientist.  As chief scientist, Taylor serves as a
conduit to station managers about the concerns and requirements of
scientists who are potential users of Freedom.

        Both Taylor and Dr. John-David Bartoe, director of Freedom's
Operations and Utilization Division, say that the modified station
design, which features shorter pre-integrated laboratory and
habitation modules, and a shorter, pre-integrated truss, still will
provide a top-flight facility for both life and materials
scientists.

        "I feel the restructuring has turned out reasonably well,"
Taylor said. "We've had a good turn around from a low point at the
beginning of this process.  At first, it appeared that science was
going to be significantly reduced, but we've been successful in
retaining capabilities.

        "Of course, any reduction in resources is going to make the
user community unhappy, but we think we've hit a happy medium that
meets both the budget constraints and users' needs," Taylor said.

        During a Space, Science and Applications Advisory
Subcommittee (SSSAAS) meeting in March, the subcommittee members's
scientist characterized the overall space station restructure as a
good move on NASA's part, but the group also said numerous concerns
must be addressed before whole-hearted support is given.

        All of the concerns presented by the SSSAAS will be
addressed during a June workshop, said Taylor. "We will either give
them answers to their specific questions, or, because we may not be
able to address all of their concerns by June, we will tell them how
we're planning to answer those questions.  In general, I'd say the
user reaction to the restructuring was positive.  They recognize the
limitations imposed on the payloads were forced by budget cuts." In
a report presented to Freedom managers in March, the space science
subcommittee said that it "finds many positive features in the
restructured station and appreciates the response of the Space
Station Freedom Program Office to the concerns expressed by our
subcommittee in November 1990.

        "The potential for performing effective research in
microgravity and life sciences in many ways is good.  In particular,
the maintenance of microgravity levels within specified limits
throughout most of the U.S. laboratory and mapping of the g-levels
are considered to be great improvements.

         "No less, exciting opportunities are provided by the
availability of resources sufficient to carry out a significant
research program in the untended intervals between utilizations
flights . . .  A number of issues now need to be addressed."

        The main concerns reflected in the space science
subcommittee report to space station managers include resources such
as power, crew, data management, utilization during the man-tended
phase, pressurization, centrifuge facility, rack allocation, early
use of racks for life science, and providing capabilityfor small-
and medium-sized attached payloads.

        Potential station users, Taylor said, are most concerned
about the availability of power, "particularly the materials science
people," because their furnace experiments alone will consume at
least a few kilowatts of power. "Historically," Taylor pointed out,
"users have always been disappointed with the power available on
spacecraft." Most researchers, Taylor said, are unaccustomed to
rationing their power needs, because, in their Earth-bound
laboratories, it is unnecessary.

        "Power now seems adequate for a much greater range of
experiment scenarios," the SSSAAS said.  While the power available
to the users is generally acceptable, the the space science
subcommittee said station designers must maintain discipline when
designing subsystems because there is "no apparent margin" between
what is required and what can be supplied.

        "We are holding the line at permanently-manned capability to
30 kilowatts or more for users," Taylor said.  This compares to a
maximum of 2.5 kilowatts available for users on Spacelab, which
flies in the Shuttle's cargo bay, and the Skylab's average of 2.3
kilowatts.

        Second on the list of concerns for researchers is the
available data-rate. "Before restructuring, the rate was 300
megabits per second, now they're talking 50 megabits downlink, which
is like Spacelab," Taylor said.  This decrease, naturally, leads to
disappointment among the scientific community, he said.  It does not
mean that the 50 megabits per second is unworkable, he said.

        "I am fairly convinced that 50 megabits per second will be
adequate," Taylor said.

        The lower data rate is attributed to using existing antenna
technology for sending data from Freedom to Earth, rather than
building a station-unique antenna, said Bartoe. The station itself
will be built with the higher data-rate fiber-optics lines, so, as
funding becomes available later on, the capability to send 300
megabits per second of data will be added back, he said.

        Third on the priority list for potential users, especially
life scientists, is crew availability -- how many are aboard Freedom
and how much time they can devote to research.  If life sciences
researchers are to cement their support for Freedom, then NASA must
reaffirm its commitment to a permanent eight person crew, the report
stated.

        Currently, the detailed planning through permanently manned
capability can support about a four-person crew. "An eight person
crew is critical to obtaining statistically valid data in human
physiology in a reasonable time period," said the space science
subcommittee report.

        "If the restructured design includes a commitment to
permanent manning with a crew of four, growing to eight, the
restructured space station will represent an invaluable life
sciences space research facility," the report stated.

        Taylor emphasized that the program is committed to an
eight-person crew, and more crew will live aboard Freedom as money
becomes available.

        According to the Report of the Advisory Committee on the
Future of the U.S. Space Program, also known as the Augustine
Committee, "The need for the space station rests squarely upon life
sciences experimentation and the development and verification of
long duration space operating systems.  These, together with its
uses for microgravity research and applications are, in our opinion,
a more than sufficient justification for space station."

        Although life sciences research alone justifies building
Freedom, Bartoe said, it "would be a real mistake to do only that."
Since Freedom is being built as a versatile research facility, it
will be possible for a rainbow of differing projects to be conducted
over Freedom's 30-year life.

        "If the station could afford to support only one major
research effort, life sciences research would be it, because it is
needed to overcome the problems of long-term human space flight,"
Bartoe said.

        "To build this large, multi-billion dollar program and not
put humans in space -- well, then we should be doing something else.
If microgravity research was all you wanted to do, then you could do
that work on something like ESA's [European Space Agency's ] future
man-tended free flyer," he said.

        The one discipline most affected by the space station
restructure assessment is the observing sciences whose payloads must
be attached to Freedom's exterior to either observe the Earth or
deep space.  Because the restructure assessment has postponed
indefinitely the attached payloads accommodations equipment, some of
the larger, more complicated payloads also must be deferred, Taylor
said.

        This move has not precluded small- and medium-sized
payloads, as well as rapid response payloads. "We think we should be
able to accommodate some attached payloads, but the details must be
worked out," Taylor said.  The SSSAAS has recommended that the
program accommodate some attached payloads by designing the standard
utility ports, already planned for the pre-integrated truss, with
mechanical attachments, data lines, environmental sensoring, and
cooling.

        While life sciences researchers will have to delay long-term
human physiology experiments until permanently-manned capability is
achieved in 1999, other aspects of life science and materials
science research will benefit, they said.

        For several years, materials scientists have been pushing
station managers for "quiet time" aboard Freedom, so long-term
materials experiments could be conducted without human disturbance,
Dr. Robert J. Bayuzick, a Space Station Advisory Committee member,
said at a March Space Station Advisory Committee meeting.  Bayuzick
is a professor at Vanderbilt University, Nashville, Tenn.

        "Every cloud has a silver lining and the microgravity
science community can make early use of the space station in a
relatively undisturbed state.  This could provide us with a good
acceleration to do work that will tell us what needs to be done,
because this science is in its infancy," Bayuzick said at the
meeting. "I've always pleaded for a window of opportunity and this
may give us that window of opportunity."

        Between 1996 and 1999 when the Space Shuttle crews will
visit Freedom for up to 13 days, known as the man-tended phase, an
array of experimentation can be conducted in microgravity science
and life sciences, as well as technology research, Bartoe said.

        Within the microgravity area, during the man-tended phase,
researchers will expand their knowledge in fluid physics, improved
inorganic crystals, and improved organic crystals.  The life
sciences will learn more about gravitational biology, animal
biology, plant biology, controlled ecological life support systems,
and human physiology.  Advanced technology investigators
willresearch very high-speed integrated circuit fault tolerance,
acoustic technology, and flight dynamics.

        The permanently manned phase of the program, which will be
ushered in during 1999, will bring even more research capabilities
to Freedom's U.S. laboratory.  The microgravity scientists will
continue their research with "next generation" crystal growth,
containerless processing, biotechnology, and advanced fluid physics,
dynamics, and combustion.  The life sciences will further
investigate the intricacies of human cardiovascular and pulmonary
physiology, radiobiology, neurophysiology, metabolism and nutrition,
endocrinology, gravitational biology, and, the controlled ecological
life support systems, among others.  Advanced technology researchers
will focus on microbiological monitoring, regenerative life support,
risk-based fire safety, laboratory robotics, and materials
dispersion studies.

        "As you can see, this is a lot of science," Bartoe said.
And these are just the projects the program is planning, he
emphasized, no one knows what research in any one of these areas
will lead to.


Centers Shift into High Gear to Hit Milestones

     Space Station Freedom's three project offices and their
contractors, known as work packages, have primary responsibility for
designing and manufacturing hardware.

        NASA's Marshall Space Flight Center and Boeing Defense and
Space Group, Work Package 1, in Huntsville, Ala., is responsible
for: the design and construction of Freedom's pressurized laboratory
and habitation modules, the working and living areas for the crew;
logistics modules, used for resupply and storage; node structures,
which con-nect the laboratory and habitation modules; and certain
subsystems internal to the pressurized modules, including the
environmental control and life support,among others.

        NASA's Johnson Space Center and MacDonnell Douglas Space
Systems Company, Work Package 2, in Houston is responsible for the
design, development, verification, assembly and delivery of the Work
Package 2 flight elements and systems, which include: the
pre-integrated truss assembly; propulsion assembly, Mobile
Servicing System transporter; resource node design and outfitting;
external thermal control; data management, among others.

        NASA's Lewis Research Center, Cleveland, Ohio, and
Rocketdyne Work Package 3, is responsible for the end-to-end
electric power system.  This includes defining the system
architecture and providing the solar arrays, batteries, and power
management and distribution systems.  The power system includes
power generation and storage.

Vice President, Partners Support Restructure

        Vice President Dan Quayle and the space station
international partners, in separate letters to NASA Administrator
Richard Truly, lauded the program in its efforts to modify the
station's design.

        "This new design reflects a focusing of the space station
program that recognizes certain fiscal and physical realities. . .
Implementing these changes will greatly increase the nation's
confidence in the feasibility of this program," Quayle stated in a
March 19 letter to Truly.

        "The importance of space station, thus, is not the size of
its span nor the power of its circuits; it is the size of the dream
and the depth of the commitment it represents," Quayle's letter
said.

        European Space Agency (ESA) Director General Jean-Marie
Luton sent Truly a letter that stated, "My assessment of the results
of this activity, based on the available data and supported by the
extensive participation of ESA staff in the exercise, is that they
are acceptable to ESA."

        The Japanese Minister of State for Science and Technology
Akiko Santo stated in a letter, "NASA's continued commitment to 75
kW and an eight man crew capability was confirmed, and the technical
impact on the [Japanese Experiment Module] development remained
minimum."

        Canadian Space Agency Director Larkin Kerwin told Truly,
"From the Canadian perspective, we believe that the restructured
program discussed by the parties at the Multi-lateral Program
Coordination meeting on January 31, 1991, has addressed our concerns
regarding the assembly and maintenance of the station.  We strongly
support proceeding with the restructured program ."

        Kerwin continued, space station "not only represents a
substantial step forward in humanity's exploration and exploitation
of space, but it is also a test of the ability of many countries to
concert their efforts toward a common goal."