Shuttle Builds Since its inception, the International Space Station (ISS) was destined to have a close relationship with the Space Shuttle. Conceived for very the International different missions, the two spacecraft drew on each other’s strengths Space Station and empowered each other to achieve more than either could alone. The shuttle was the workhorse that could loft massive ISS elements into space. It could then maneuver, manipulate, and support these pieces John Bacon Melanie Saunders with power, simple data monitoring, and temperature control until the Improvements to the Shuttle pieces could be assembled. The ISS gradually became the port of call Facilitated Assembly of for the shuttles that served it. the International Space Station Lee Norbraten The idea of building a space station dates back to Konstantin Financial Benefits of the Tsiolkovsky’s writings in 1883. A space station would be a small colony Space Shuttle for the United States Melanie Saunders in space where long-term research could be carried out. Visionaries in Psychological Support— many nations offered hundreds of design concepts over the next century Lessons from Shuttle-Mir and a half, and a few simple outposts were built in the late 20th to International Space Station century. The dreams of an enduring international space laboratory Albert Holland coalesced when the shuttle made it a practical reality. As a parent and child grow, so too did the relationship between the shuttle and the ISS as the fledgling station grew out of its total dependence on the shuttle to its role as a port of call. The ISS soon became the dominant destination in the heavens, hosting vehicles launched from many spaceports in four continents below, including shuttles from the Florida coast. 130 The Space Shuttle and Its Operations Creating the In April 1984, STS-41C deployed Spacelab and Spacehab Flights one of the most important and International Space comprehensive test programs—the Skylab had been an interesting first Station Masterpiece— Long Duration Exposure Facility. step in research but, after the Saturn V STS-32 retrieved the facility in January production ceased, all US space station in Well-planned 1990, giving critical evidence of the designs would be limited to something Increments performance and degradation timeline of similar to the Orbiter’s 4.6-m (1 5-ft.) materials in the low-Earth environment. payload bay diameter. The shuttle Building this miniature world in the It was a treasure trove of data about had given the world ample ways vacuum of space was to be the largest the micrometeoroid orbital debris to evolve concepts of space station engineering challenge in history. It was threat that the ISS would face. NASA’s modules, including a European Space made possible by the incomparable ability to launch such huge test fixtures Agency-built Spacelab and an capabilities of the winged fleet of and to examine them back on Earth American-built Spacehab. Each module shuttles that brought and assembled the after flight added immensely to the rode in the payload bay of the Orbiter. pieces. The space station did not spring engineers’ understanding of the These labs had the same outer diameter into being “out of thin air.” Rather, it technical refinements that would be as subsequent ISS modules. made use of progressively sophisticated necessary for the massively complicated engineering and operations techniques The shuttle could provide the necessary ISS construction. that were matured by the Space Shuttle power, communications, cooling, Program over the preceding 17 years. The next stage in the process would and life support to these laboratories. This evolution began before the first involve an international connection and Due to consumables limits, the shuttle International Space Station (ISS) the coming together of great scientific could only keep these labs in orbit assembly flight ever left the ground— and engineering minds. for a maximum of 2 weeks at a time. or even the drawing board. Through the experience, however, Early Tests Form a Blueprint NASA ran a series of tests beginning with a deployable solar power wing experiment on Discovery’s first flight (Space Transportation System [STS]-41D in 1984) to validate the construction techniques that would be used to build the ISS. On STS-41G (1 984), astronauts demonstrated the safe capability for in-space resupply of dangerous rocket propellants in a payload bay apparatus. Astronauts practiced extravehicular activity (EVA) assembly techniques for space-station-sized structures in experiments aboard STS-61B (1 985). Several missions tested the performance of large heat pipes in space. NASA explored mobility aids and EVA handling limits during STS-37 (1 991 ). Space Shuttle Atlantis (STS-71) is docked with the Russian space station Mir (1995). At the time, Atlantis and Mir had formed the largest spacecraft ever in orbit. Photo taken from Russian Soyuz vehicle as shuttle begins undocking from Mir. Photo provided to NASA by Russian Federal Space Agency. The Space Shuttle and Its Operations 131 astronaut crews and ground engineers discovered many issues of loading and Astronaut Shannon Lucid floats in the deploying real payloads, establishing tunnel that connects optimum work positions and locations, Atlantis’ (STS-79 clearances, cleanliness, mobility, [1996]) cabin to the environmental issues, etc. Spacehab double module in the cargo bay. Lucid and her Shuttle-Mir crew mates were already separated In 1994, the funding of the Space from the Russian Station Program passed the US Senate space station Mir by a single vote. Later that year, and were completing end-of-mission Vice President Al Gore and Russian chores before their Deputy Premier Viktor Chernomyrdin return to Earth. signed the agreement that redefined both countries’ space station programs. That agreement also directed the US Striving for Lofty Heights— when the shuttle could angle enough Space Shuttle Program and the Russian And Reaching Them to meet the Russian orbit. space program to immediately hone the complex cooperative operations The biggest effect on the shuttle in Thus, in a cooperative program with required to build the new, larger-than- this merged program was the need to vehicles like Mir (and later the ISS), the dreamed space station. That operations reach a higher-inclination orbit that shuttle had only a tiny “window” each development effort would come through could be accessed from Baikonur day when it could launch. The brief a series of increasingly complex flights Cosmodrome in Kazakhstan. At an chance to beat any intermittent weather of the shuttle to the existing Russian inclination of 51 .6 degrees to the meant that the launch teams and space station Mir. George Abbey, equator, this new orbit for the ISS Mission Control personnel often had to director of Johnson Space Center, would not take as much advantage of wait days for acceptable weather during provided the leadership to ensure the the speed of the Earth’s rotation toward the launch window. As a result of the success of the Shuttle-Mir Program. the East as had originally been planned. frequent launch slips, the Mir and ISS Instead of launching straight eastward control teams had to learn to pack days The Space Shuttle Program immediately and achieving nearly 1,287 km/hour with spontaneous work schedules for engaged Mir engineers and the Moscow (800 mph) from Earth’s rotation, the the station crew on a single day’s Control Center to begin joint operations shuttle now had to aim northward notice. Flexibility grew to become a planning. Simultaneously, engineers to meet the vehicles launched from high art form in both programs. working on the former US-led Space Baikonur, achieving a benefit of only Once the shuttle had launched into the Station Program, called Freedom, went 901 km/hour (560 mph). The speed orbit plane of the Mir, it had to catch to work with their counterparts who difference meant that each shuttle could up to the station before it could dock had been designing and building Mir’s carry substantially less mass to orbit for and begin its mission at the outpost. successor—Mir-II. The new joint the same maximum propellant load. The Normally, rendezvous and docking program was christened the ISS Mir was already in such an orbit, so the would be completed 2 days after Program. Although NASA’s Space constraint was in place from the first launch, giving the shuttle time to make Shuttle and ISS Programs emerged as flight (STS-63 in 1995). flagships for new, vigorous international up any differences between its location cooperation with the former Soviet The next challenge of the 51 .6-degree around the orbit compared to where states, the immediate technical orbit was a very narrow launch window the Mir or ISS was positioned at the challenges were formidable. The Space each day. In performing a rendezvous, time of launch, as well as time for Shuttle Program had to surmount many the shuttle needed to launch close to ground operators to create the precise of these challenges on shorter notice the moment when the shuttle’s launch maneuvering plan that could only be than did the ISS Program. pad was directly in the same flat plane perfected after the main engines cut as the orbit of the target spacecraft. off 8½ minutes after launch. Typically, there were only 5 minutes 132 The Space Shuttle and Its Operations Generally, the plan was to launch The mechanism—called an The Russian wires were designed to then execute the lengthy rendezvous Androgynous Peripheral Docking be soldered into each pin and socket preparation the day after launch. System—became an integral part of while the US connector pins and sockets The shuttle conducted the last stages of the shuttle’s future. It looked a little were all crimped under pressure to their the rendezvous and docking the next like a three-petal artichoke when seen wires in an exact fit.