The Working Space Shuttle
Getting those first four development flights "under the NASA belt" had been a long, tough job. The extensive delays had caused a backlog of payloads, more than the Space Shuttle could reasonably expect to handle in the near future. Some commercial communications satellites originally on the Shuttle manifest had already shifted to Ariane, a lively new unmanned competitor built by the European Space Agency. Deltas and Atlas-Centaurs, scheduled to be deactivated by this time, were still being launched, although on reduced schedules. The lower cost of a Space Shuttle flight made this vehicle very attractive to potential customers, but there was a long waiting period for cargo space. For the moment, there were payloads enough for all four vehicles.
NASA still faced the formidable task of working up to a launch schedule of two Shuttles a month. That could only be done when the full fleet of four authorized orbiters were all flying. Challenger was to be the second one off the production line, followed by Discovery and then Atlantis. But Columbia had to fly the next mission because it was still the only orbiter available.
STS-5 lifted off at 7:19 EST on Nov. 11, 1982. This first paying mission carried two commercial communications satellites, a Satellite Business Systems-3 and Anik-3, both Hughes HS-376 spacecraft. Each was also the next satellite in line in a series, their predecessors having been launched on unmanned vehicles. And there would be more in both lines to follow.
This first Space Shuttle launch of two communications satellites was also symbolic of the future. The geosynchronous communications satellite had spawned a new industry-telecommunications from space-and it was generating two billion dollars a year in revenue. No other civilian application of space technology had caught on so quickly, or been so rapidly converted into moneymaking commercial ventures. And with an already thriving business expected to benefit from the less expensive launch fees promised by the Space Shuttle, future growth seemed unlimited.
Satellite Business Systems soon paid to have its fourth satellite launched by the Space Shuttle, and Telesat of Canada sent up both an Anik C-2 and Anik D-2. Indonesia decided to augment or replace aging satellites in its Palapa domestic communications system. A Shuttle took up Palapa B and Palapa B2. Western Union, the first American company to have its own domestic communications satellites, sent up Westar VI. American Telephone & Telegraph sent up Telstar 3-C. India sent up Insat 1B, which was an unusual combination spacecraft that could photograph the Earth every 30 minutes as a weather satellite, relay television signals direct to small antennas like a direct broadcast satellite, and also serve as a general telecommunications spacecraft.
Hughes Aircraft, which had built more satellites for other firms than any American company, decided to enter the burgeoning field of commercial satellite communications. Hughes established a domestic system of three spacecraft called Galaxy, where the design was based on its proven HS-376 model. Their business plan required transponders to be sold in orbit to individual buyers, who might or might not be regulated common carriers. This allowed Hughes itself to avoid becoming a common carrier. All three Galaxy spacecraft were launched on Delta vehicles. Hughes also built a new spacecraft too large for the Delta called Syncom IV, for which it kept ownership but leased the entire capacity to the U.S. Navy. Two Syncom IVs were launched in 1984 and two more in 1985.
NASA launched the largest communications satellite of them all for itself. This was the first Tracking and Data Relay Satellite, or TDRS. This massive spacecraft was designed to become a tracking station in the sky, capable of replacing most of the net of ground stations that NASA had for many years maintained around the world. With two TDRS satellites in geosynchronous orbit and on opposite sides of the world, a Shuttle orbiter could maintain constant communication with the ground for 85 percent of its flight time. With the ground stations, the average was 15 percent. And the satellites, once built and launched, were far less costly to maintain than the ground stations they replaced.
Many communications spacecraft were successfully deployed from the orbiter, but three failed to reach geosynchronous altitude when their attached rocket motors were fired. Two of these were the Palapa B2 and Westar VI, both launched on the STS 41-B mission. Their Propulsion Assist Module rocket motors failed shortly after ignition. Left in stable but low orbits, both spacecraft were retrieved during mission STS 51-A in November 1984 and brought back to Earth for refurbishment. The third was TDRS, which was being boosted by the new Inertial Upper Stage. Fortunately, the rocket engine burned long enough to carry TDRS halfway to its planned 22,300-mile (35,889-kilometer) geosynchronous altitude. And there was enough extra onboard attitude control propellant to allow its own small thrusters to gradually work the huge satellite up another 11,000 miles (117,703 kilometers). Over a period of several months, NASA controllers at Goddard slowly and carefully raised TDRS, using many short burns to prevent overheating the small rockets. It eventually reached its planned station, and went to work.
TDRS had cost about 100 million dollars. It also had the potential to save NASA much more than that over the next 10 years. Saving TDRS was thus a double financial benefit to NASA. TDRS also was badly needed to support the upcoming Spacelab flight. Only this large and complex satellite had the capacity to properly relay to ground stations the huge amounts of data that Spacelab would generate.
The second major area of Space Shuttle utilization was scientific experimentation, using human beings to operate the instruments in orbit instead of automated spacecraft or ground control. By far the largest and most complex science program was that of Spacelab, which was scheduled to eventually fly two or three times a year. But smaller and less complicated instruments would fly on virtually every Shuttle flight, performing a wide variety of experiments and observations.
It was sometimes difficult to distinguish between true scientific exploration of the unknown, and the development of new or improved products through in-orbit work in materials technology. There were also many experiments in the latter category, often flying side by side with science experiments in the Spacelab or on a pallet. Their primary purpose was to take advantage of the high vacuum and microgravity of space to produce unique or highly valuable products for eventual sale in commercial markets.
Spacelab 1 flew on the ninth Shuttle mission, and was an immense success. The first payload was deliberately designed to cover the five major areas of scientific inquiry and technical development, to each of which an entire Spacelab might be devoted in the future. The primary purpose was to demonstrate what could be done in each area, rather than attempt to do extensive research or experimentation. The science categories were atmospheric physics and Earth observation, space plasma physics, astronomy and solar physics, and life sciences. Materials science and technology was the fifth area, where development work could be done to provide useful commercial products, based on what had already been learned about the unique manufacturing conditions available in space.
Spacelab also featured the flight of two non-NASA astronauts, payload specialists who had special training in operating the Spacelab instruments but only a minimum of the rigorous training required of NASA astronauts. One of these was from the European Space Agency, builder of the Spacelab and operator of half of the experiments aboard. The second was a researcher sent by the Massachusetts Institute of Technology. An unusually capable ground communications system enabled the operating crews in orbit to perform some work under close direction of the primary scientific investigators on Earth. To completely analyze the immense amounts of data Spacelab 1 obtained was a task of several years duration.
The third Shuttle development flight had introduced a new type of experiment into orbit. The Shuttle Student Involvement Program experiments became a continuing payload on many succeeding launches. Another category, the Getaway Specials, were carried in sturdy containers in the cargo bay, and for these there was a reduced charge. They were intended for students at the college level who could obtain sponsors willing to foot the bill, or for individuals or companies who had small experiments they wanted to see performed in orbit.
Another large though less active science project was the reusable Long Duration Exposure Facility (LDEF), sponsored by NASA. This huge cylinder, some 30 feet (9.1 meters) long and 14 feet (4.3 meters) wide, was carried into space to be left for a year or more. The body of LDEF consisted primarily of some 86 trays, which accommodated more than 50 experiments some being too large to fit into a single tray). These were largely passive in nature, with few or no requirements for power and movement. One of these was a huge number of tomato seeds, which were to be distributed to school children and planted after having been in space. They were to be compared to plants grown at the same time from seeds not exposed to space, to see if any differences appeared in the mature plants.
NASA also deployed a scientific spacecraft its own, the Earth Radiation Budget Satellite. or ERBS. Its purpose was to measure the incoming heat from the Sun and its re-radiation into space, to learn more about how the Earth managed to avoid heating up from the constant intake of sunlight.
NASA continued the work started during previous manned space flight programs on how humans work and function in space, including attempting to discover the cause and cure of "space sickness." This temporary and sometimes debilitating illness strikes about half the members of astronaut crews during the first days in weightlessness. A continuing series of experiments were performed over many flights. The life sciences experiments on the Spacelab I mission provided extensive data on human reactions in space, forming a data base against which other reactions could be measured. Although not a major problem, space sickness is an annoyance which astronauts would rather not have to endure.
From the beginning of space flight, the promise of unique materials and products that could be produced in microgravity had intrigued chemists and engineers. With the Space Shuttle the ability to return to space again and again became a reality, making it practical to plan a continuing series of developmental steps leading to an operational capability. Several forward-looking Companies already had agreements with NASA, and more were pending. One of the earliest was McDonnell Douglas, working in association with the Ortho Pharmaceutical Corp.
The first experimental Continuous Flow Electrophoresis System had flown on STS-3. This was a biological separation device that, in microgravity, could produce drugs of such purity and strength that their value far exceeded the expense of producing them in space. Manufacturing these drugs on Earth, in the grip of gravity, was possible, but the quantities produced were small and prohibitively expensive. High-volume production in microgravity could lower the price and make the drug more widely available, thus benefiting untold numbers of people, while still making a good profit for McDonnell Douglas and Ortho. This was the type of manufacturing in space that NASA wanted to encourage.
After several flight tests, McDonnell Douglas sent up a larger version of its machine on the 12th Shuttle flight, along with its own operator, engineer Charles Walker. Walker thus become the first commercial payload specialist. Although some mechanical problems were encountered, Walker resolved them in time to produce a large quantity of drugs and Prove that the concept was practical and workable. More flights were set for the future.
Strangely enough, the first product actually made in space and sold for money was Produced by NASA. The Monodisperse Latex Reactor, which had first flown on STS-3 along with the CFES, on later flights produced a quantity of tiny, highly uniform latex beads that had a variety of scientific and industrial uses. Beads of this almost microscopic size that were also uniform could be used to calibrate scientific and measurement devices that were very difficult to certify any other way. Beads that size produced in gravity could not be made uniform enough to be useful. Sold in small packets, the beads brought in enough money to partially defray the costs of the several experiments.
The 3M company also made a long-term development agreement with NASA, and flew a set of experiments on the 14th mission. It dealt with the diffusive mixing of organic solutions, and was the first of more than 70 planned organic and polymer science experiments. 3M later reported the tests had been highly successful, although the equipment was produced in about one-third the time normally required to prepare a flight experiment.
West Germany, which had the bulk of the materials experiments on Spacelab 1, made reservations for 25 Getaway Specials for similar investigations. This member of the European Space Agency also independently decided to take an entire Spacelab flight for an extensive materials science investigation.
A new area that NASA pioneered during the early years of the working Space Shuttle was the recovery and refurbishment of failed satellites. Although many spacecraft in orbit and on interplanetary trips had failed and been restored by ground control, no satellite had ever been physically repaired in space, or recovered and brought to the ground for repairs. The Shuttle did both within a single year, 1984.
Solar Maximum Mission, a NASA scientific satellite to study the Sun, had failed after a short operational life. Ground controllers felt certain it could be repaired by replacing one electronic box and a few components. The crew that placed the Long Duration Exposure Facility in orbit went on from there to rendezvous with Solar Max. It was captured and brought into the cargo bay, where two astronauts wearing space suits replaced the needed box and installed new components. The satellite was tested and released back into orbit, where it functioned for another five years before re-entering the Earth's atmosphere.
The WESTAR VI and Palapa B-2 communications spacecraft that had been left in low orbits by the failures of their attached booster stages were recovered and returned to Earth. This was possible because the orbits they had reached were low enough that ground controllers could bring them back down within range of the orbiter. The rendezvous proved much easier than wrestling the two satellites into the cargo bay and securing them there, but two astronauts in space suits eventually succeeded. Once back in the Hughes factory, the two spacecraft were examined, and proved little the worse for wear. Both were refurbished and prepared for a second try at useful life in orbit.
In between these two missions NASA performed a test which has a high potential for future applications-refueling satellites in orbit. Refueling gear and hydrazine tanks were carried up on STS 41-G in the cargo bay, Astronauts in space suits demonstrated that it was possible to attach hoses and valves to exhausted satellites and pump hydrazine into their dry tanks. Since using up their fuel was the most common reason satellites were "put out to pasture" (placed on the inactive list), the experiment proved it was possible to revive those the Shuttle could reach.
The ability to repair and refuel satellites in orbit, or recover and return some to the ground, opened up a whole new chapter in the utilization of space. And all three tasks were accomplished as secondary objectives, after the main business of each mission had been completed. The Space Shuttle and its crews were steadily expanding their horizons.
Most Space Shuttle missions lasted from six to 10 days, and the size and capacity of the vehicle made it possible to carry a large crew. Six-person crews became common, seven were flown when necessary, and the STS 61-A Spacelab D-1 mission had a crew of eight. Crews that large, with a week in orbit, could accomplish a great deal of work. There was time for many smaller projects along with the major ones.
Two of these smaller projects were photographic in nature. A group of observatories had banded together and arranged for a special camera, called Cinema-3 to be flown in the cargo bay and in the crew cabin on several missions. Its large lens, when operating in the totally air-free and extremely clear region of space, returned spectacular film suitable to be shown on planetarium domes. IMAX, another large-film camera system operated by the astronauts from inside the orbiter, did an equivalent job for showing on extra-large wall screens. The latter was available to more people, and shows appeared at several places. These included the KSC visitors center, Spaceport USA, and the Smithsonian's Air and Space Museum in Washington, D.C.
On one mission NASA deployed a solar cell wing out of the cargo bay, one equipped with only a few cells of different types. The experiment was designed to test the wing itself more than the cells. Folded, this 13-foot (4-meter) wide sheet stood only seven inches (18 centimeters) high in its container, but it erected to a height of 102 feet (31 meters). An operational version, fully covered with solar cells, could produce a great deal of power for future in-orbit applications.
The astronauts also proved the design of their extravehicular space suits in actual practice. After this was accomplished, they operated the Manned Maneuvering Unit, or MMU, a large device which the astronaut attaches to his body somewhat like an oversized backpack with arms. The MMU has built-in thrusters and a control system, among many other features, enabling an astronaut to maneuver freely away from the orbiter. The MMUs were used during all the retrieval and refurbishment operations, allowing astronauts to fly to and around the satellites, once the orbiter had brought them to the vicinity.
The astronaut crews performed many other experiments and miscellaneous tasks during the first operational years, doing varied and different kinds of jobs than had been attempted previously in the space environment. The Space Shuttle was proving that it possessed the versatility and multicapabilities that its designers had promised from the beginning.
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