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"6_10_8_6.TXT" (20222 bytes) was created on 04-08-90
STATION BREAK: VOL. 2, NO. 2, FEBRUARY 1990
Director 's Goal to Meet PDR December Deadline, March on to First Element
Launch in 1995
"In one year I want to be able to say that we are one year closer to first
element launch," said Richard Kohrs, Space Station Freedom director,
Washington, D.C.
"I want to maintain the preliminary design review schedule and the first
element launch -- that's my goal."
Meeting that goal this calendar year means rolling full steam ahead toward
the completion of the program's preliminary design review (PDR) in
December.
"My outlook for the year and keeping the PDR on track is optimistic. I
think we will be successful," Kohrs said. "We've got a lot of work to do
in the meantime, though."
The PDR is a technical review of the basic design and is conducted prior
to, or very early in, the detailed design phase. Following the detailed
design phase comes the critical design review (CDR), which is the
technical review of specifications and will certify the design of all
flight hardware. Typically, no flight hardware is built during these
phases, except test or prototype pieces. The critical design review
should be completed in 1992. Once the design passes the critical design
review, the design will be frozen and manufacturing will begin.
Checkpoints such as these are placed in the hardware development and
mission phases of the Freedom program to ensure the integrity and success
of the program.
"In order to meet the PDR and CDR, the 1990 and 1991 budgets have to
remain as they are. We can't sustain any major budget cuts and stay on
schedule," Kohrs stressed. Space station officials are preparing for
their first Congressional fiscal year 1991 budget hearing later this
month. No official numbers had been released at press time.
During the fall, NASA officials conducted an extensive review and
rephasing of the program to meet a budget cut of nearly $300 million for
fiscal year 1990 and to reduce technical, schedule, and cost risk in the
development of Freedom. First element launch will remain in the first
quarter of 1995, but subsequent milestones have been stretched out.
Freedom's operating funds for 1990 were reduced to $1.749 billion, $298
million less than President Bush's request of $2.05 billion.
Just as the first assembly launch has remained virtually unaffected by the
budget cuts, so will the users' needs. Once Space Station Freedom has
reached final assembly complete, the facility "will meet all the user
requirements we had before," Kohrs said.
"I had to delay and defer some items, but there are actions in the system
to put those back into the program. We're working with the users to make
sure their needs are met."
Management of Polar Platform to Change
NASA Administrator Richard H. Truly has approved a plan to transfer the
management of the polar orbiting platform, currently under development by
the Office of Space Flight as part of the Space Station Freedom program,
to the Office of Space Science and Applications, which has responsibility
for the proposed Earth Observing System (EOS).
President Bush has made preservation of the environment a top priority.
NASA's EOS is a key element of the overall Mission to Planet Earth
initiative, whose purpose is to produce the understanding needed to
predict changes in the Earth's environment. EOS will observe the Earth
from polar orbit to understand the processes that control the global
environment.
EOS is planned to be a major new effort within NASA, and the unmanned
polar platform will be the first piece of hardware to be built for this
program. "This gives the responsibility for managing the EOS platform to
the office responsible for carrying out the EOS mission," said Dr. William
B. Lenoir, associate administrator for Space Flight. "In a management
sense, it puts the development and operation of the platform closer to the
users of the platform."
Plans for EOS observations have been developed in coordination with NASA's
international partners. "This transition plan was discussed with our
international partners, and we have assured them that agreements between
us will be honored in all regards," said Lenoir.
The international partners include Japan, Canada, and the European Space
Agency.
The role of the Goddard Space Flight Center in Greenbelt, Md., which
manages the EOS program and the polar platform, has not been altered by
this decision. Goddard will continue to play a vital role in the Freedom
program as the center responsible for developing the Flight Telerobotic
Servicer, a space robot that will be used in the assembly and maintenance
of the manned base.
Goddard will retain its management responsibility for developing the
platform with General Electric Astro Space, Princeton, N.J., as the prime
contractor. Current plans call for the U.S. platform to be launched on a
Titan IV rocket from Vandenberg Air Force Base, Calif. The platform will
have an orbital lifetime of at least five years.
The transition of the management of the polar platform will be conducted
over the course of the 1990 fiscal year. Beginning in fiscal year 1991,
complete responsibility for the polar platform will be transferred to the
Office of Space Science and Applications.
Truly Names Former KSC Deputy Director as OSF Deputy Associate
Administrator
NASA Administrator Richard H. Truly named Thomas E. Utsman as the deputy
associate administrator for Space Flight (Management). Utsman is Truly's
most recent appointment since the Offices of Space Flight and Space
Station merged (See January Station Break). The adjacent chart shows the
overall Office of Space Flight organization, which includes Richard Kohrs,
director of the Space Station Freedom program.
In his new capacity, Utsman will have overall responsibility for assisting
William B. Lenoir, associate administrator for Space Flight, in the
day-to-day oversight management of the Space Flight programs, which
include the Space Station Freedom and the Shuttle programs. Specific
responsibilities will include overseeing procurement activities, assessing
program management performance and conducting long-range operational
planning. George Abbey will remain deputy associate administrator.
Utsman was both deputy director of Kennedy Space Center, a post he held
since August 1985, and director of Space Transportation System Management
and Operations, with responsibility for the engineering management and
technical direction of return-to-flight activities in the post-Challenger
era, which he performed from December 1986 until March 1989.
Columbia Microgravity Experiment Yields Information for Station Research#
Experimenters who have worried if an astronaut running on a treadmill will
ruin results of a Space Station Freedom microgravity experiment will have
more information to go on now that Columbia has returned from its 11-day
January mission.
For the first time, a Shuttle experiment attempted to quantify how
disturbances in orbit affect the sensitive microgravity processes being
tested.
Although it will take about six months to analyze the seven crystals grown
during the Columbia mission, "the crystal growth and the recorded
disturbances during flight were successful," said co-principal
investigator Don Thomas, a materials scientist in Engineering's Structures
and Mechanics Division at Johnson Space Center. Mission Specialist Bonnie
Dunbar also was a co-principal investigator.
While math models that show what affects various disturbances might have
on microgravity experiments are already being worked, "This Shuttle
experiment will help us refine those mod-
els," said Richard Kohrs, director,Space Station Freedom, Washington, D.C.
The Microgravity Disturbances Experiment (MDE) was conceived, developed,
and coordinated at Johnson Space Center in Houston, Texas.
"We know that the lower the microgravity level, the better," Thomas
explained.
"We know that these levels generally provide high quality crystals--larger
crystals with fewer defects. What we don't know is how low do you need to
go in the microgravity level."
#
Thomas said the experiment is unique because it is the first attempt to
correlate measurements of onboard disturbances with the success of a
crystal growing attempt.
While in orbit, every change in speed or direction increases the amount
of acceleration or 'gravity' experienced inside the spacecraft.
Since every action generates an opposite and equal reaction, even small
movements can make minute changes in an orbiting Shuttle's speed or
direction--and affect the level of microgravity.
A cough or sneeze is estimated to raise the level to a
hundred-thousandth or millionth of Earth's gravity. A crew member running
on the exercise treadmill could raise it to a hundredth or thousandth of
Earth's gravity. An engine burn could raise it to a tenth or a hundredth.
These changes are believed to affect microgravity materials processing,
but the precise extent has not been measured. "In almost every other
materials processing experiment that's been done so far, they've always
tried to avoid any disturbances at all. They've wanted to get as good a
microgravity level as they could. We know we get the best crystals that
way.
"Nobody has taken a look at what happens if you do have these
disturbances. Can we tolerate the crew running on the treadmill? Because
we're always going to have crewmen running on treadmills, especially on
space the station. We're always going to have man operating in a
spacecraft environment, you're going to have these perturbations in the
microgravity level. We hope to be able to come out of this and say 'These
are the effects of those disturbances.'"
Disturbances such as the shock of someone running on a treadmill will be
softened as much as possible by shock-mounting or isolation. However,
inescapable disturbances, such as a shuttle docking with Freedom, will be
avoided by scheduling experiments around these tasks, Kohrs said.
The MDE involved seven samples of commercial purity indium, a
well-characterized material with a relatively low melting point. Indium
is used in the production of advanced electronic devices.
Basically, a furnace in the fluid experiment apparatus was expected to
melt a poly-crystal of indium, which resolidified in microgravity as a
single, more perfect crystal. The melts were timed to coincide with
specific activities onboard Columbia, such as crew exercise on the
treadmill. The crew also recorded many other disturbances.
Lewis Research Center to Lead Microgravity Experiment Facilities Study
Lewis Research Center in Cleveland, Ohio, was named the lead center for a
definition study and conceptual design of two microgravity experiment
facilities that will be aboard Space Station Freedom.
The facilities are the Modular Combustion Facility and the Fluid
Physics/Dynamics Facility. A team of engineers and designers from an
engineering team and its support service contractors, Analex Corp. and
W.L. Tanksley Inc., have been defining the experimental and Space Station
Freedom requirements for the two modular, user-friendly facilities. Based
on these requirements, concept designs are being developed for each
facility.
The proposed Modular Combustion Facility will support research experiments
dealing with the study of combustion and its byproducts. Research into
the mechanisms of combustion in the absence of gravity, with attendant
lack of a gravity-induced convection, will help to provide a better
understanding of the fundamentals of the combustion process caused by the
lack of gravity-induced convection.
The proposed Fluid Physics/ Dynamics Facility will be used by the
community of scientists and engineers to carry out experiments in theories
of fluid behavior, provide improvements in thermophysical property
measurements, and provide scientific and engineering data related to a
wide variety of fluids-applications systems.
NASA Selects TRW Inc. for Earth Observing
System Contract Negotiations
The Langley Research Center in Hampton, Va., has selected TRW Inc.,
Redondo Beach, Calif., for contract negotiations to develop space flight
instruments for NASA's polar orbiting platform and Space Station Freedom
as part of the proposed Earth Observing System (EOS). The goal of Eos is
to advance scientific understanding of the Earth's land masses, oceans and
atmosphere, their interactions, and how the Earth's system is changing.
The two-phase contract is estimated at $37 million. Phase one, a
cost-plus-fixed-fee contract, is for one year and has an estimatedvalue of
$700,000. The contract started in January. Phase two, which will not be
implemented until EOS is approved by the administration and Congress, is a
cost-plus-award-fee option. It would be for eight years and would be
worth about $36.3 million. The work will be performed by TRW's Space and
Technology Group, Redondo Beach. The company would design, build, and
deliver up to six instruments for the Clouds and the Earth's Radiant
Energy System (CERES) and provide support for integration, launch, and
mission operations (Nov. 1989 Station Break).
Joint Science Utilization Study Results Reported
The Joint Science Utilization Study (JSUS) was an international, one-year
study of payloads for Space Station Freedom sponsored by the NASA Office
of Space Science and Applications (OSSA).
The primary goal was to establish a basis for optimizing the scientific
use of the available pressurized volume and other resources by sharing
some experiment and support equipment among the international partners.
The study focused on the pressurized laboratory payloads at a point in
time three years after the assembly complete configuration.
The results of the study, including areas of common concern to the
international science community, have been published in the final report:
"Toward Effective International Cooperation for Science on Space Station
Freedom".
The JSUS was carried out by the science offices of the international
partners in the Space Station Freedom program: the National Aeronautics
and Space Administration (NASA), the European Space Agency (ESA), the
National Space Development Agency of Japan (NASDA), and the Canadian Space
Agency (CSA). Each of the representatives provided detailed information
regarding their agency's plans.
The two major 'splinter' groups, Life Sciences and Materials Science,
examined the planned facilities, goals, and themes of all partners. By
identifying opportunities for sharing and eliminating unnecessary
duplication of equipment, they established a coordinated reference set of
payloads that they felt made best use of the resources while maximizing
the science they could achieve.
Analysis of the partners' payload plans showed 102 pieces of equipment
that were duplicated by at least two of the four partners. By sharing
equipment and eliminating unnecessary duplication, science experimentation
can be enhanced and expanded to make more effective use of the limited
space and resource envelopes that will be available. Consequently, each
partner increases those scientific capabilities to which it has access.
The study accomplished its chartered objectives and goals, but, more
basically, it was the first time the science user representatives met to
share information and to learn about each other's research programs. The
most significant result of the entire JSUS was the demonstration that
sharing among the users of Freedom on an international level has many
benefits and should be further pursued. The basis for cooperation among
the science users of Freedom was firmly established.
Dr. B. Siegel, the chairperson of the Joint Science Utilization Study, is
the program manager for Pressurized Element Payloads for Space Station
Freedom within the NASA Office of Space Science and Applications. For
more information, contact Dr. Siegel at (202) 453-1689.
Space Station Furnace Facility: A Research Tool for Freedom
In the January issue of Station Break, OSSA highlighted the Centrifuge
Facility, which is designed to study the effects of weightlessness on
small animals and plants. Scientists are similarly interested in the
effects of zero- or microgravity on the solidification of electronic
materials, metals and alloys, composite materials, glasses and ceramics.
The Microgravity Science and Applications Division (MSAD) plans to install
and operate several multi-user instruments on Space Station Freedom to be
used for research under long-term microgravity conditions in the fields of
materials science, biotechnology, and observations of fundamental
phenomenon. The largest of these instruments, the Space Station Furnace
Facility (SSFF), will perform melt, vapor, and solution growth
experiments, as well as thermophysical property measurement of materials.
Materials scientists wish to understand the role of gravity in the
solidification of materials, as well as to uncover effects previously
hidden by the overpowering force of gravity during the transition from
liquid (or vapor) to solid.
The presence of gravity during solidification has a great effect on
material properties in the resulting solid. These effects of gravity on
material properties, such as electron mobility in semiconductors, arise
from convection, varying pressure, or sedimentation of components in the
melted material. The absence of gravity during the solidification of a
material may well change the entire make-up of a specific material.terials
research under microgravity conditions using the Space Shuttle and
Spacelab, and works with NASA centers to develop furnaces for those
vehicles. There are several limitations in using the Space Shuttle for
solidification research, however. Many proposed investigations require
experiment durations longer than the average five-to-seven day Shuttle
mission, and some individual experiments would take even longer than
Extended Duration Orbiter missions of 16 to 28 days. For those
experiments that can take place within the Shuttle time constraints, many
times only a few samples can be solidified, since the furnace needs time
to cool to remove the sample and then time to reheat.
Also, because of the low level of electrical power available on the
Shuttle (compared to ground laboratories), the furnace equipment must be
specially designed to conserve power and energy, and this can affect the
thermal performance of the instrument and the quality of the sample
solidified. Power availability also limits the size of the sample which
can be melted and grown. It is desirable to locate the furnace
instruments within the manned environment so the flight crew can act as
researchers and repairmen. However, the power level is even more limited
in the Shuttle middeck or Spacelab module.
Development of the SSFF will allow furnace instruments to take advantage
of crew access, high power availability, long-duration microgravity, and
other Freedom resources.
The facility design will be built around the "Core concept," where a
single space station rack of SSFF avionics will provide the main interface
to space station services that furnaces require.
The Core will consist of those subsystems common to many types of
investigations and will be centralized for use by all furnace experiments.
The actual furnaces will be multi-user modules, capable of long life, high
reliability and reconfiguration on-orbit to support many different types
of experiments within each general area.
Most furnace modules will be developed by MSAD, but modules may also be
contributed by other NASA organizations, domestic commercial firms, or
NASA's foreign partners. Single furnace
modules may take up a fraction of one rack, or may require a unique
support structure in the place of several racks.
For planning purposes, the SSFF is allocated five racks of U. S.
laboratory space, including the Core rack.
The SSFF is one of the six major facilities currently planned for Space
Station Freedom's pressurized laboratory by MSAD of NASA Headquarters.
For more information on the SSFF, contact Mr. Joel Kearns, Program Manager
for Solidification Systems, MSAD, at (202) 453-1490.