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STATION BREAK, VOL. 1, NO. 2, JULY/AUG, 1989


Engineers  Continue Post-Flight  SHARE  Tests

Engineers at the Johnson Space Center say they think the difficulties with
Space Station Freedom's cooling system experiment were caused by a design
problem in the heat-pipe.

Since the Space Station Advanced Heat-pipe Radiator Element (SHARE)
experiment flew aboard the Shuttle Discovery in April, engineers have
studied flight data and conducted numerous ground tests to determine the
cause of its sporadic operation during the flight, said Steve Glenn,
project engineer.

The experiment didn't operate as expected because of difficulties in
priming the heat-pipe, a data analysis team, composed of technical experts
from JSC and industry, concluded after studying post-flight SHARE data.

"Indications from our ground tests show that the SHARE hardware is
identical to the preflight configuration and test data also comparable to
that prior to flight, which would rule out a mechanical failure," Glenn
said.  "We now feel that a small design problem in the heat-pipe prevented
complete priming, and this is a problem that would only be apparent in a
zero-g environment."

While the SHARE experiment fell short of initial expectations,
investigators don't consider it a failure, Glenn said.  From a strict
technical standpoint, the experiment was only partially successful,
considering high preflight expectations.  From a broad station
perspective, however, SHARE was highly successful since it allows for
redesign of a critical station component early in the program prior to
building the actual station panels, he said.

Because a previous, less extensive Shuttle flight test and other SHARE
experiments went well, engineers expected a flawless experiment aboard the
Discovery.  "We truly were expecting things to go as planned, but
sometimes things don't work out the way you planned."

Unimpressive in its outward appearance [SHARE looks somewhat like a slat
from a venetian blind] the heatpipe uses no moving parts, working instead
through the surface tension of ammonia.  Heat-pipe systems have cooled
satellites, but have never before been applied to manned spacecraft.

The SHARE hardware includes two small 'pipes' bored through an aluminum
core that runs through the center of a 51-foot-long, foot-wide radiator.
The two pipes, one slightly larger than the other, are connected by a
narrow slot.  The evaporator consists of six parallel legs that feed into
a perpendicular manifold which in turn supplies a single leg condenser.
This configuration closely resembles the geometry of a pitch fork.

During the orbital test, three electric heaters warmed the evaporator end
of SHARE.  During operation, the evaporator, which works along the same
principle as the wick of an oil lamp, pulled liquid ammonia from the
smaller pipe, where it was vaporized by the heat.  The vapor then carried
the heat the length of the radiator through the larger pipe.  Then the
radiator dissipated the heat into space, leaving cooled, condensed
ammonia.  Small circumferential grooves on the wall of the larger pipe
then allowed condensed ammonia to drop back through the narrow slot into
the smaller pipe, which recirculated the liquid ammonia back to the
evaporator.

As part of the post-flight trouble shooting effort, engineers investigated
physical abnormalities as well as operational anomalies by comparing
post-flight data with data.  A zero-g simulation of a plexiglass SHARE
test article aboard the KC-135 showed an inability of the manifold to
properly prime.  [The KC-135 flies at a steep angle of ascent and then
drops at a steep angle of descent to achieve weightlessness at the curve
in between.]

Results of a 1-g end-to-end test of the flight panel, which compared
post-flight and data, also showed no hardware flaws.  Engineers x-rayed
SHARE to find out what the liquid level is and to find out if there is
enough liquid present.  Glenn said the liquid level is identical to the
level.

Engineers are awaiting the results of a thermal vacuum test to validate
the heat-pipe's predicted minimum operating temperature.


Tech  Audit  Completed,
Goal  to  Reduce  Design Complexity  Met

Managers at the Space Station Program Office in Reston, Va., completed a
technical audit in May that will help streamline and simplify the
station's design.

"There is concern that the tech audit changed requirements and that's not
so," stressed Marc Bensimon, associate director for the Space Station
Freedom Program.  "We didn't change any of the fundamental requirements
imposed on the program from Level I and above.  The real focus was on
derived interpretation of these requirements and on the plans for their
implementation."

Managers used the technical audit as a tool to spot program projects that
were too complex and will be  proposing changes to simplify them, said
Bensimon.   About 223 issues were raised by the audit team.  After careful
review some were found to be nonissues, some were already being addressed
and nearly 80 were considered for immediate action.  The decisions made
will be followed by the appropriate program documentation.

The technical Audit will serve as a guide for engineers during the
preliminary design process by making sure their design ideas are in line
with program requirements.

"We needed the technical audit as a guide, so we wouldn't waste too much
time and money designing  something that was too complicated, too
expensive," Bensimon said.  Although design simplification was the
dominant objective, the audit did look for areas with potential life cycle
cost gain.  This included areas that may cost more money upfront to design
and build, but would cost less money over the station's lifespan.

All in all, Bensimon said, the technical audit exceeded expectations in
burrowing through details of the program to weed out unnecessarily
demanding design requirements and unduly complicated designs concepts.
"We packed a lot of work into a short period of time, the centers were
enthusiastic and we discovered and took care of more issues than we
expected."


Space  Station  Program Leadership  Selected

NASA Administrator Richard Truly has named former Shuttle astronaut Dr.
William B. Lenoir associate administrator for the Office of Space Station.

Lenoir, who started work June 1, is replacing James Odom, who retired from
NASA on April 30 after 33 years of service.  Thomas Moser, acting
associate administrator, retired May 12 after 26 years with NASA.

Truly also appointed Richard Kohrs as director of the Space Station
Freedom Program at NASA Headquarters in Washington, D.C.  Kohrs, former
deputy program director of the National Space Transportation System at
Johnson Space Center in Houston, Texas, will be responsible for the
design, development and future operations of the space station.  Ray
Tanner wasnamed deputy director of Space Station Freedom Program and
Operations in Reston, Va.

"Bill Lenoir is highly qualified and brings with him experience in NASA,
space flight and private sector activity.   I am extremely pleased that he
is willing to return to the government," Truly said. "In addition, Dick
Kohrs' experience in the Space Shuttle program makes him the best choice
to lead Space Station Freedom through the challenges facing this program."

One of Lenoir's first duties will be to study consolidating the
administration for the Space Shuttle and space station programs, Truly
said.  "This would be a consolidation of the executives and not the
programs," Truly stressed.  "Since the Shuttle will be the transportation
mode for the station, it's important that we coordinate the executive
offices of both."  Lenoir is scheduled to complete this study before
year's end.

Lenoir was vice president and a member of the board of directors of
Booz-Allen & Hamilton, Inc.,  Bethesda, Md., and also managed that
company's program support contract for space station.

Lenoir served as a NASA astronaut from August 1967 to September 1984.  He
earned a bachelor of science degree in electrical engineering in 1961, a
master of science degree in 1962 and a doctorate in 1965 from the
Massachusetts Institute of  Technology.


Canada's Contribution
to Space  Station Freedom

The Mobile Servicing System (MSS) is Canada's contribution to the space
station program.  Canada also will participate in the use and operation of
the orbiting complex throughout its lifetime and Canadian astronauts will
be part of the space station crew on a regular basis.

The MSS will play a role in space station assembly and maintenance, moving
equipment and supplies around the station, supporting astronauts working
in space and servicing instruments and other payloads attached to Freedom.
It also will  be used for  loading and unloading materials from the
Shuttle  cargo bay.

The entire system will consist of equipment located both in space and on
the ground.  One component, the Mobile Servicing Center, will be a "roving
space robot", riding aboard space station on a traveling base provided by
the United States.

The MSC is scheduled to be flown to the space station's orbit on the third
Space Shuttle mission dedicated to the station's assembly.

A main feature of the Mobile Servicing System's state-of-the-art robotic
equipment will be the next generation of CANADARM, Canada's contribution
to the U.S. Space Shuttle program.  The MSS Manipulator will be about the
same size as CANADARM but over three times as strong and more dextrous.

A separate, smaller robot, called the Special Purpose Dextrous Manipulator
(SPDM), will have two arms for more delicate jobs such as cleaning
surfaces, replacing faulty components and working on the station's
electrical circuits, fuel lines and cooling system.

The SPDM can work either as a companion to the big arm (connected to its
end) or alone (attached to the station's truss structure).  Its arms can
work together or separately.

The combination of the two robots gives the MSS the skill to do many kinds
of work associated with the assembly and maintenance tasks aboard space
station.

Installations for ground operations and logistics will be in Canada.


NASA Selects Flight Telerobotic Services Development Contractors

NASA's Goddard Space Flight Center, Greenbelt, Md., has selected the
Martin Marietta Space Systems Co., Denver, Colo., to design and build the
flight telerobotic servicer (FTS) for use in the assembly and maintenance
of Space Station Freedom.

The $297 million contract, which took effect July 1, will provide for the
design, development, test, integration, launch support, training and
ground support systems, mission operations support and sustaining
engineering of all hardware and software required for the FTS program
mission.

A key element of the Freedom program, the FTS will employ technologies not
used on previous NASA spacecraft.  Spinoffs from robotic technologies
developed in the FTS program are expected to advance U.S. industrial
automation capabilities.

The six-foot high servicer will consist of three highly dextrous robotic
arms, twin video cameras for viewing, and an advanced control system.  It
will be launched in the mid-1990's aboard a Space Shuttle and remain in
orbit with Freedom.  Once in orbit, astronauts will operate the servicer
from work stations aboard the space station or Shuttle by either direct
manipulator control or programmed command sequences.  The robot will
enable astronauts to direct routine assembly and maintenance work without
leaving the Shuttle or space station, thereby increasing crew productivity
and safety.

Eventually, using advanced computer programming called artificial
intelligence, the robot will think like a human to perform complex tasks
like replacing satellite components.


Experts Deem High Definition TV Test at Kennedy Space Center a Success

A High Definition Television (HDTV) test at Kennedy Space Center during
the March Shuttle launch marked the first demonstration of a long distance
transmission over a fiber-optic cable.

Viewers watched the crisp real-time transmission in Orlando, Fl., via a
circuitous 110 mile fiber optic line.  "A transmission of live HDTV over
such a long distance had not been attempted before," said Dr. Indraneel
Paul, a BellCore researcher working with NASA on the experiment.

Investigators are forging ahead with research into HDTV transmission and
formats, and NASA people are examining HDTV use aboard Space Station
Freedom.  "Our current NTSC television system will be in the phases of
obsolescence by the turn of the century," said Thomas Bentsen, Manager of
Advanced Video Systems Development for the Office of Communications.
"This test provided us with necessary data to understand how fiber
transmission and the use of HDTV equipment can be done reliably and
economically," Bentsen said.  "These data are critical to expanding our
understanding of HDTV technologies if we are to use them aboard the
station."

HDTV, which offers 35mm like quality to television, has more than twice
the resolution of current television, displayed with 1125 scan lines,
compared to 525 lines for today's television.


Canadian Space Agency Completes Preliminary Design Review

The Preliminary Design Review (PDR) for the Canadian elements of Space
Station Freedom was held in Toronto in March and shows the program is
still on track.  Technical managers and officials of the Canadian Space
Agency met with managers and officials from Spar Aerospace to review
system level requirements and designs.  Experienced NASA and European
space station staff also participated.   PDR is a necessary self
evaluation where managers check design concepts and make sure they meet
program requirements.

"It was outstanding," said Jim Johnson, NASA's liaison officer in Canada.
"A very significant event for the project."

About 165 people participated and contributed to the success of the nine
day conference during which 15 documents were intensively reviewed.
Another 42 documents were distributed for comments.  "We were looking for
omissions and errors in consistency between documents," said Don Peterson,
PDR coordinator.  "They are the baseline from which the new work can
begin."

Canadian Program Director, K.H. Doetsch, indicated that apart from
allowing the preliminary design to be considered, the review was
particularly valuable in forging the links between the partners that are
necessary to successfully integrate the various elements of Freedom.

The next major review, the Critical Design Review which examines the
detailed designs, is planned for March 1992.


Committee  Advises  OSSA
on  New  Science  Capabilities

One of Space Station Freedom's main functions is to support science and
applications research conducted in and from Earth orbit.  A particular
challenge in space station development is to ensure that the developed
support capabilities are responsive to the anticipated requirements of the
research communities that will be the principal users.  Conversely, it is
equally important that the users design their experiment systems with an
understanding of the capabilities and limitations of the space station.
To foster the communications that will help achieve these ends, the Space
Station Science and Applications Advisory Subcommittee (SSSAAS) was
established as a subcommittee of the Space Science and Applications
Advisory Committee of the NASA Advisory Council.

SSSAAS advises the NASA Office of Space Science and Applications (OSSA) on
the new capabilities to be made available by the space station program and
how these may be most effectively utilized, and the NASA Office of Space
Station on how the space station program may most effectively support
potential science and applications users.

SSSAAS held its fourth meeting at NASA Headquarters in Washington, D.C.,
April 27-28.  Several broad issues regarding the scientific utilization of
the space station were addressed: 1) communication and information
systems' connectivity and user interface; 2) science operations and
support, particularly crew utilization and payload integration issues; and
3) international science activities, especially as related to laboratory
commonality and opportunities for cooperation among the partners.

The importance of item (2) was underscored by the decision of the SSSAAS
members to overlap their meeting with the last day of the OSSA Crew
Utilization Workshop, held at the BDM Corp. in Columbia, Md., April 24-26.
SSSAAS members attended the summary session of this workshop on April 26,
where they heard the splinter group reports, comments from international
partners, and closing remarks.  It was evident that many of the crew
utilization issues of concern to SSSAAS had been addressed during the
workshop and will continue to have visibility in the Advisory Council
structure.(See article, page 5)

The formal SSSAAS meeting at NASA Headquarters on the 27th and 28th
included presentations on the information systems for the space station
and the Earth Observation System, and a report on the progress of the OSSA
Information Systems Strategic Plan.  Science operations and experiment
support presentations included detailed discussions of plans for
laboratory support equipment in the U.S. lab module and a presentation on
the transition of experiments from Shuttle payload (e.g. in Spacelab) to
the space station.

Life sciences topics included a presentation on the possibility of
relocating the 1.8-meter centrifuge into a node adjacent to a space
station laboratory module, and the progress of an evaluation of animal
visitation requirements that could have an impact on the design of live
specimen transport facilities.


OSSA  Develops  Science  Crew
Requirements at  Workshop

On April 24-26 OSSA held a workshop in Columbia, Md., to develop and
recommend OSSA policy and positions for Space Station Freedom science crew
requirements.

Participants were from a wide range of users including the science
disciplines within OSSA, Space Station Science and Applications Advisory
Subcommittee (SSSAAS) members, representatives from other U.S. science
agencies, technology and commercial users, international science partners,
astronaut office representatives, and representatives of the Office of
Space Station and space station project offices.  More then 60 people
participated in the workshop.

A general session was devoted to the history of and current planning for
crew operations,  selection, and training.  Subsequent sessions focused on
the requirements in each of the these areas for Life Sciences users,
Microgravity Sciences and Applications users, and attached payload users.
Splinter sessions were held in parallel to distill and summarize
positions, recommendations, and issues in each topic area.  Summary
presentations were made by each splinter group to the general workshop.

During the three day workshop, there were many lively discussions, often
about longer stay times and more demanding payload responsibility on the
station compared with Spacelab operations.  Items discussed include: the
need for both generalists and specialists among the crew; the need for
studying experimental results on-orbit (on-orbit characterization) vs.
sending them rapidly back to the ground for study (rapid sample return);
the need for high-fidelity trainers for the crew; the role of telescience,
and the remote control of experiments on the station by investigators on
the ground.

An OSSA position paper on crew requirements for Space Station Freedom is
being prepared for release in late summer, and a more complete report of
some aspects of the workshop is planned for release in the fall.  For more
detail on the OSSA Crew Requirements workshop, contact Dr. Bette Siegel,
Program Manager Pressurized Element Payloads, Space Station Utilization
Branch, [phone].


OSSA  Manages  Science  Utilization

OSSA is responsible for planning U.S. scientific utilization of Space
Station Freedom.  As one of the many elements of this planning, OSSA has
created an organization consisting of various OSSA-sponsored NASA centers.
They will provide overall management and integration support to science
user activities for both pressurized and attached payloads on the Space
Station Freedom manned base.

Principal support is provided by the Marshall Space Flight Center, Johnson
Space Flight Center, and Kennedy Space Center, with other support
activities from Goddard Space Flight Center, Langley Research Center,
Lewis Research Center, the Ames Research Center, and the Jet Propulsion
Laboratory.

In planning for such activities, OSSA concluded it would be advantageous
to preintegrate OSSA and U.S. science requirements prior to delivery to
Freedom, manage allocated science resources, and perform tradeoffs within
and among the various science and applications discipline organizations.
The management framework for this unified integration management approach
is called SUM (Science Utilization Management).

This methodology has been formalized in a Space Station Science and
Applications Utilization Plan (SSAUP) released in August 1988, and
developed in more detail in a Science Utilization Management for Freedom
Manned-Base Study Report released in March 1989.  In the SSAUP, various
other U.S. science agencies have agreed to work through OSSA to develop
their own utilization activities.

SUM activities provide direct NASA field center support to the Flight
Systems Division at NASA Headquarters.  Functions and activities that
support OSSA in this role include: coordination of payload requirements;
integrated science mission planning; coordination of integrated crew
training requirements;supporting science input to Freedom planning
documents; and planning and management of integrated science operations.
Other responsibilities involve working with the various science
disciplines and planners and non-NASA government agencies such as the
National Institutes of Health, the National Science Foundation, and
others.  The purpose of these interfaces is to define and coordinate
payload development support and interface requirements, and to  conduct
accommodations and requirements analyses.

Other functions of SUM include analytical integration, payload
development, physical integration, and mission operations support as
requested for payload developers by the science discipline offices.
Participation in various panels and working groups or reviews at the field
centers and at NASA Headquarters is required.  SUM responsibilities also
include supporting technical and policy interactions with the
international partners on behalf of OSSA through various reviews, and
active participation in related working groups.  In addition, the SUM
group would forms a primary link to the NASA field centers that have work
package responsibilities.

For more information about SUM and its science utilization management
responsibilities, contact Dr. Philip Cressy, Chief of the Space Station
Utilization Branch, [phone]


Using  Freedom  as  a  Vehicle
for  In-Flight  Research

With the advent of  the space station comes a unique opportunity to
conduct relatively long-term in-space technology experiments.  The Space
Shuttle and the space station are two excellent examples where operational
space vehicles serve not only as carriers for in-space technology
experiments but also as objects of research interest themselves.

Similar to the Orbiter Experiments project on the Shuttle, which supply
data in the areas of aerodynamics, aerothermodynamics, and materials,
these same type of experiments on the space station will provide valuable
data to the research, technology, and engineering community on large,
manned space vehicles.  Experiments can span several areas and
disciplines: structures and dynamics, controls, power systems, thermal
systems, environment controls and life support systems, on-orbit
operations, and information and data management systems.

To ensure that this particular type of experimentation is integrated
effectively with the appropriate station subsystem, the development of the
experiment should occur concurrently with the station development phase.

The Office of Aeronautics and Space Technology (OAST) has initiated
efforts to exploit this in-space research opportunity of outfitting the
space station with instruments.  One of the most fruitful experiments will
investigate be space structures.  For example, the Space Station
Structural Characterization Experiment (SSSCE) will collect on-orbit data
to characterize the structural dynamics of the space station and develop
modeling techniques for large space structures.

A study of the SSSCE was conducted from February 1988 to December 1988.
This study showed  experiment is feasible if the excitation of structural
modes is achieved through reboost techniques and subsequent free-decay
measurements of acceleration are performed.  The proposed characterization
would involve 100 or more acceleration measurements on truss nodes and
major masses, such as photovoltaic arrays and pressurized modules, to
define the critical global vibration modes.   Given the complexity of the
measured information, it is important to conduct experiments on the early,
simpler assembly configurations prior to progressing to the baseline
configuration.  The experiments consume relatively little in resources and
have minimal impact on space station  operations.  Thus, Freedom offers an
early and unique opportunity to develop modeling techniques for large
space structures which can then be experimentally verified in space
through the SSSCE.  This experiment is being conducted by the Langley
Research Center  in close coordination with Work Package 2 at the Johnson
Space Center in Houston, Texas.

For more information, contact Dr. Roger Breckenridge, Langley Research
Center [phone], or Dr. Judith H. Ambrus, NASA Headquarters
[phone].


Space  Station  Development  Duties
Spread  Among  HQs  and  Centers

Because Space Station Freedom is such an intricate and complicated system
to design, build, and operate NASA has a three-tier management system to
ensure program efficiency.

The three levels are: Level I, the office of the Associate Administrator
for Space Station; Level II, the Space Station Freedom Program Office in
Washington, D.C. and Reston, Va.; and Level III, the NASA field center
project offices.

Level I is responsible for policy and overall program direction.  Level II
is responsible for  program management and technical content.  And Level
III, comprised of various NASA centers and their contractors, is
responsible for design, development, testing and operation of space
station systems and components.

Level III is divided among four centers known as Work Packages (WP): WP 1
is the Marshall Space Flight Center in (MSFC) in Huntsville, Ala.; WP 2 is
the Johnson Space Center (JSC) in Houston, Texas; WP 3, the Goddard Space
Flight Center in Greenbelt, Md.; and WP 4, the Lewis Research Center
(LeRC) in Cleveland, Ohio.

MSFC and its prime contractor, Boeing Aerospace, will design and build:
the habitation module; the U.S. laboratory module; the logistics elements
[which hold support equipment and supplies]; and the environmental control
and life support system (ECLSS) and resource node structural elements.
Marshall also is responsible for operations capability development
associated with Freedom payload operations and planning.

JSC and its prime contractor, McDonnel Douglas Space Systems Co., will
manufacture: the integrated truss assembly; the propulsion system; the
mobile transporter system; the extra vehicular activity system; the
external thermal control system; the attachment systems for the Space
Shuttle; the guidance, navigation and control system; the communications
and tracking system; the data management system; the airlocks; and outfit
the resource nodes provided by MSFC [a node is a small pressurized
cylinder that serves as command and control center and as pressurized
passageways among modules].  In addition, Johnson is responsible for
flight crews, crew training and crew emergency return.

GSFC and its prime contractor, the Astro-Space Division of General
Electric Company, will build: the accommodations for attached payloads;
and the U.S. unmanned polar-orbiting platform.

LeRC and its prime contractor, Rocketdyne Division of Rockwell
International, will design and build Freedom's electrical power and
distribution systems.

Langley Research Center in Hampton, Va., is responsible for space station
evolution to meet future needs such as increased research and development
activities.  This means that Langley must conduct mission, systems, and
operations analyses; systems level planning of options/configurations/ and
coordinating and integrating study results by others.

The Jet Propulsion Laboratory (JPL) in Pasadena, Calif., working as a
member of Level II management, is responsible  for the Program
Requirements and Assessment.  JPL also supports the research and
development(R&D) effort for the Flight Telerobotic Servicer and its
evolution, and the Office of Aeronautics and Space Technology R&D effort.

Until Kennedy Space Center's Space Station Processing Facility (SSPF)  is
completed in 1994, Kennedy is dedicated to systems engineering and
integration, ground support equipment management, operations and customer
support project control and logistics systems.

About a year before the first launch, the various work packages will begin
shipping the station elements to KSC.  Kennedy will offload the station
components and scrutinize both hardware and software for post-shipment
health.  When all the appropriate checks are made, the station elements
will be loaded into the Space Shuttle's cargo bay and then launched.


Tethers  as  Research,  Operational
Tools  for  Space  Station  Freedom

Toward the end of the 20th century, when the U.S. has established a
permanent presence in space,the basics of access to, operation in, and
return from space will nearly be mastered.  The U.S. and its partners will
then begin to expand the repertoire of orbital space capabilities to
provide versatility, increase performance, and develop fundamentally new
operations.  Tethered systems, for example, potentially offer a powerful
new space capability.

For the past few years, conceptual studies and analyses have shown that
the tethering of two or more orbiting spacecraft [two objects on opposite
ends of a cable that can vary in length] can offer many unique, dynamic
and functional properties.  The potential uses of tethers for Space
Station Freedom can be categorized by length.

Applications with the shorter tether lengths offer greater likelihood of
earlier implementation.  For example, Freedom's surrounding environment
could be completely mapped by repeatedly "spin casting" a passive
diagnostic package away from the station on a line, or tether, 1
kilometer(more than a half mile) long.  An electromagnetic cast off, a
fiber optic data line, and a small battery-powered instrumentation package
would permit measurements to be made during reel-in.  Another passive
application requiring a tether of a kilometer or so would provide remote
positioning of a payload away from Freedom to provide dynamic or
electromagnetic isolation or to conduct possibly hazardous operations,
such as moving a fuel depot.

The possibility of generating electric power through use of a conducting
tether also exists.  A joint U.S.-Italy flight demonstration of the
Tethered Satellite System (TSS) planned for a January 1991 Shuttle flight
is expected to generate electricity using a 20 km (12.5 mile)
electrodynamic tether with an electron gun mounted at the Shuttle end.
However electrodynamic interactions with Freedom would require careful
examination and resolution.

Tethered platforms might be deployed both below and above Freedom to
lengths of just over 6 miles (10 km) each.  By  controlling the lower
tether length, fine control of the vertical position of the system
center-of-mass could be provided to offset variations in the stations
distribution of mass.  The lower system could also provide gravity
gradient stabilizationtethered around Freedom's pitch and roll axes.

Using the upper tether could provide microgravity levels onboard an
attached crawler-elevator.  Among other tether applications proposed for
the space station are the payload acquisition from lower orbit or payload
deployment to higher orbit these would require active involvement by
Freedom operators.  Downward deployment of a tethered research package
into the ionospheric "F" layer at 300 km (186 miles) or to the edge of the
outer atmosphere at about 80 miles (130 km) would require tethers of
150-300 km(93-186 miles), which would clearly introduce more operations
complexity.

The development and flight of the reusable TSS is an ongoing joint
NASA-Aqenzia Spaziale Italiano (ASI, Italy's space agency) flight
demonstration program.   The proposed second flight, TSS-2, is currently
being developed.  It would deploy a 100 km (62 mile) tether downward to
about 130 km (80 miles) for aerothermodynamics and atmospheric science
measurements.  Also in early 1991 an expendable tethered research package
to investigate tether dynamics is scheduled to be flown on a Delta II
launch vehicle.  Instrumentation for these dynamic measurements is being
developed.  Furthermore, in addition to ASI's major involvement in
tethers, at the recent Third International Conference on Tethers in Space,
the European Space Agency expressed interest in conducting and/or
participating in tether experiments.

For more information, contact John L. Anderson, NASA Headquarters,
Washington, D.C., [phone].

Commercial  Program  Signs
MOU  with  Coca-Cola  Company

NASA Assistant Administrator for Commercial Programs James T. Rose and
former acting Associate Administrator Thomas L. Moser have signed a
memorandum of understanding (MOU) with the Coca-Cola Company.

This MOU helps meet the President's Commercial space initiative which
directs NASA to rely as much as possible on the private sector.

The MOU will further the exchange of information which explores space
applications of fluid dynamics, gas liquid separation and metering
technologies.  Such dialogue may broaden the base of understanding of
this technology, particularly as it pertains to the support of long
duration manned space activities.  This technology could be used in other
areas such as hydroponic agricultural technology, water recycling system
components, hydraulic applications, gas chromatography, medical products
and equipments.

The Coca-Cola Company has built with their own resources, a prototype/test
demonstration unit to test this space technology.

An MOU with NASA enables the exchange of information between NASA and a
commercial company in a specified area of space application and is
typically a precursor to a Joint Endeavor Agreement with NASA.