![]() ![]() One pointed out the need for efficient and simple man-machine interfaces, and called for having ATOLL, FORTRAN IV, and COBOL compilers available to the engineers 49. Some hinted at the direction the eventual system would take. Phase B Shuttle studies conducted by a number of contractors included concepts of the checkout system 48. Kennedy would launch eastward, continuing the established situation and giving Kennedy the opportunity to try for the development of the checkout system. Vandenberg was expected to handle polar orbit launches and most military payloads. Since existing facilities could be modified at both Vandenberg and Kennedy, the cost-conscious administrators settled on those two launch sites. All inland launch sites were thus eliminated, and just Kennedy Space Center, Vandenberg Air Force Base, and a site in Texas remained under consideration 47. In March 1972, NASA selected the solid rocket booster/external tank configuration for the Shuttle. On the other hand, modifying existing Apollo/Saturn facilities at Kennedy and adding new equipment where needed would cost $355 million, a significant savings 46. One study placed the cost of a new facility with these characteristics at $1.9 billion. Chief among these were a hypergolic and cryogenic fuels facility, a hangar for the orbiters and boosters, a mating building, a control center, the launch pads, and a runway with a safing bay for emptying residual fuels after landing. Project staff examined a number of sites and made projections of the cost of an "ideal launch site" that would have all the facilities necessary for handling the Shuttle. Such a design could theoretically be launched from anywhere in the United States isolated enough to handle aborts safely. Most designs were predicated on a winged booster, which would return to the launch site immediately after separation from an orbiter with internal fuel tanks. Kennedy Space Center Gets the Job During the late 1960s NASA began studies of the configuration of the eventual STS. Given the organization of NASA at the time, this was one of the biggest surprises as well. One of the biggest changes from the Apollo/Saturn preflight checkout systems is that Kennedy Space Center became responsible for the development of the Launch Processing System. Building the present system, during which almost all preflight testing and preparation is done under control of software, and in which much of the countdown, sometimes even including the calling of "holds," is done by computing machinery, was a remarkable effort 45. Still, some engineers needed to be convinced that hardwired testing could be successfully eliminated, even though the last 20 hours of a Saturn countdown was 85% automated 44. As Henry Paul, who headed the Launch Processing System development for NASA, said, "Automation.becomes a requirement for operations, not an elective" 43. Clearly, there was no way NASA could do the Shuttle checkout with Apollo concepts 42. Even with this reduction, nearly 46,000 measurements have to be made and monitored in real time in the process of preparing a Shuttle for launch 41. One study indicated that only 53% of the tests done on a Saturn V would need be repeated if the spacecraft were reusable 40. NASA put considerable effort into examining commercial aircraft maintenance techniques to see what could be adopted for Shuttle use. Compared to the 5-month checkout of a Saturn V and its 3-day countdowns, this seemed outrageous, especially since the Shuttle would be no simpler than an Apollo/Saturn. A projected fleet of three orbiters would be limited to a maximum 2-week turnaround between flights and a 2-hour countdown in order to achieve that many firings 39. Chapter Seven - The Evolution of Automated Launch Processing - The shuttle launch prosessing system When NASA began planning for the Space Transportation System (STS), it espoused ambitious requirements, such as an eventual launch rate of 75 per year. Computers in Spaceflight: The NASAExperience
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