October 1993
NF202
NASA's Gleaming Satellite Adapted As Economic Giant
The legacy of NASA's-and the worlds-first passive
communications satellite is a booming metallization industry with
scores of applications.
Launched August 12, 1960, Echo I captured the world's
imagination, and was the debutante of the year-bigger, brighter and
more brilliant than almost any star in the firmament.
The process of coating plastics with a mist of metal to create a
foil-like effect-metallization transformed a 1950s small scale
manufacturing operation producing decorative metallized plastics
into a flourishing industry-thanks to NASA's efforts to share their
successful adaptations of an existing technology. The results range
from food packaging and aircraft covers to clothing and survival
equipment.
NASA first dealt with this type of metallization when developing
its Echo I satellite in the 1950s. Developed at the NASA Langley
Research Center, Hampton, Virginia, the world's first passive
communications satellite was simply a very large balloon, its
diameter close to the height of a 10-story building. It served as a
space relay station for reflecting communication signals from one
point on Earth to another.
When developing Echo I, NASA needed a special material for the
balloon's skin. For "bouncing" signals, the material had to be
highly reflective. It also had to be lightweight and exceptionally
thin so that it could be folded into a beach-ball-size canister for
delivery to orbit, where the balloon would automatically inflate.
The material selected was mylar polyester coated with a reflective
layer of tiny aluminum particles so fine that Echo's skin had a
thickness about half that of the cellophane on a cigarette
package.
Metallization was not an exotic space-age development. It
originated in the 19th century, but the technology and its
applications developed slowly. By the late 1950s, when Echo was in
design status, the metallization industry barely existed. The
market was slim and production was very limited. Metallicized
plastics were being produced mostly for decorative purposes.
MORE SPACE APPLICATIONS
Echo requirements triggered extensive research and development
(R&D) of metallization techniques by NASA that led to further
space applications, mostly for thermal radiation insulation. NASA
used metallized film on virtually every U.S. spacecraft, from early
satellites of Echo's vintage through the manned Apollo and Skylab
programs. NASA also used the material as a reflective insulator to
protect astronauts from solar radiation and to protect sensitive
spacecraft instruments.
The growing field of applications spurred R&D by
manufacturers to improve vacuum metallizing techniques, that
resulted in development of a broad, still-growing line of
commercializedmetallized products. Today, there are many diverse
commercial products, including insulated garments, life rafts,
reflective blankets, wall coverings, window shades, food packaging,
candy wrappings and photographic reflectors.
SURVIVAL EQUIPMENT
A super-reflective, nonporous, waterproof and rot-proof laminate
known as TXG was developed from metallization technolology for
production of a survival raft that provides maximum protection from
heat, cold, wind and rain. The laminate was once used by NASA as a
reflective canopy far visual and radar detection of the rafts that
returning Apollo astronauts used while waiting to be picked up by
ships or helicopters after splash down.
A reflective kite of gold TXG was produced to serve as a highly
effective distress indicator in an emergency. The SOS Signal Kite
can be flown as high as 200 feet to enhance radar and visual
detectability. It provides campers, hikers, mountain climbers and
boaters with a lightweight, easily portable emergency signaling
device. Made of metallized nylon, the kite spans six feet but
weighs only six ounces.
Other products include protective fabrics that retain up to 80
percent of the user's body heat, helping to keep a person warm for
hours in cold weather or to prevent post-accident shock. All are
remarkably compact. The Space Emergency Bag, for instance, opens
into a three-by-seven-foot personal tent-blanket and then folds
into a three ounce package the size of a deck of playing cards.
AIRCRAFT PROTECTION
The TXG laminate has also been used to develop heat shields,
custom tailored reflective curtains that cover the windshield and
windows of parked aircraft to protect electronic equipment from
heat buildup and ultraviolet radiation. A multi-layered automatic
shade system for large windows has also been adapted.
FOOD PRODUCTS
Alure, a metallized plastic material developed and manufactured by
the St. Regis Paper Company, has been developed to meet a multiple
packaging material need: good eye appeal, product protection for
long periods of time, and the ability to be used successfully on a
wide variety of food packaging equipment. When the cost of aluminum
foil skyrocketed, packagers sought substitute metallized materials
but experiments with a number of them uncovered problems. Some were
too expensive, some did not adequately protect the product, some
were difficult for the machinery to handle. Alure offered a
solution.
Alure effectively blocks out light, moisture and oxygen and,
therefore, gives packaged foods a long shelf life. It also runs
faster on machines than materials used in the past, and decreases
product waste. The net is increased production.
CLOTHING
One of the most popular metallized products is a lightweight
jacket fabricated by several companies from NASA's
super-insulation. The 10-ounce reversible jacket absorbs warmth
from the sun, and with the silver-colored side next to your body,
it retains a large portion of body heat. In warm weather, you wear
the silver side out to reflect the sun's rays.
In a similar model, a gold metallized polyester film is bonded
to a tear resistant fabric to allow radar reflection, as well as
higher visibility under all light conditions.
Like other jackets, the materials protect against heat or cold
and do not absorb moisture.
Other products marketed include a three-ounce Thermos Emergency
Blanket, that reflects and retains up to 80 percent of the user's
body heat, thus helping to prevent post-accident shock. It will
keep a person warm for hours under emergency cold weather
conditions, and has been used by participants in the Boston
Marathon as a post-race measure to prevent loss of body
temperature.
The metallization story is an excellent example of the aerospace
spinoff process. This instance involves a technology that existed
before the NASA application, but space use prompted far greater
commercial applicability. It is a great example, where an adaption
of existing technology for an aerospace requirement resulted in
expanded markets for the technology to the benefit of the U.S.
economy. More often, spinoffs stem from technology specifically
developed for the aerospace purposes and are later adapted to Earth
needs and conveiniences.
Echo the "Star"
The world's first passive reflector communications satellite,
Echo I came down from its nearly circular orbit 800 miles above the
Earth May 23, 1968. The 100-foot globe of aluminum-coated mylar
plastic, in orbit for more than sevenand-one-half years, was
battered by space dust and meteoroids so that its skin was wrinkled
like a prune.
During its travels, it was probably seen by more people than any
other man-made object in space. It was visible to the unaided eye
over most of the Earth. Echo fan clubs sprang up in schools;
newspapers and radio stations reported daily predictions where it
would pass. Boy and Girl Scout troops waited for her...as did many
thousands of others in big and little communities. In slightly more
than seven-and-a-half years since launch, Echo I flew around the
Earth more than 35,600 times, in excess of one billion miles. It
was familiar to millions of people throughout the world as a fast
moving star in the sky.
Proposed uses were:
- as an Earth satellite to reflect radio and radar signals
- as a lunar probe to the moon
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