As long as flight does not conform to design, that is, has "anomalies," the design remains provisional it is not fully understood and the system is "developmental" not "operational." Both disasters revealed that NASA truncated the examination of risk by deeming the shuttle "operational" by treating as "successful" flights that did To count as a success, a shuttle flight must perform as the design predicts, not merely return "safely" to Earth. In balancing safety and performance the shuttle's design both represents NASA's understanding of the system and predicts that the shuttle's flight will safely meet performance requirements. The careful, honest examination of risk cannot be done once it must continue as flight experience accumulates. Given this legitimate political commitment to human space exploration, the space shuttle program is ethically and politically acceptable insofar as the agency in charge, NASA, promotes careful and honest examination of the human risks and, in reaching the compromises unavoidable in balancing safety against performance, involves those most subject to the risks and those making the political commitment.
The losses of the space shuttles Challenger in 1986 and Columbia in 2003 dramatically illustrated the risks involved in the human exploration of space, and provide starkly instructive case studies in the ethics of science and technology.Ī central mission of the National Aeronautics and Space Administration (NASA) is human exploration of space. Highlights of the NASA Glenn contributions to the impact testing are presented with emphasis on the use of high speed digital photography to document theses tests.SPACE SHUTTLES CHALLENGER AND COLUMBIA ACCIDENTS This paper summarizes the Columbia Accident and the nearly seven month long investigation that followed. Researchers at the NASA Glenn Ballistic Impact Laboratory have participated in several of the impact test programs supporting the Accident Investigation and Return-to-Flight efforts. Digital high-speed cameras were used extensively to document these tests as significant advances in recent years have nearly eliminated the use of film in many areas of testing. Supporting this effort are many test programs to evaluate impact threats from various debris sources during ascent that must be completed for certifying the Shuttle system safe for flight. Following the accident investigation, NASA turned its focus to returning the Shuttle safely to flight. These tests ranged from fundamental material characterization tests to full-scale Orbiter Wing Leading Edge tests. Supporting the findings of the CAIB, were numerous ballistic impact testing programs conducted to investigate and quantify the physics of External Tank Foam impact on the RCC wing leading edge material. During reentry, this breach allowed superheated air to penetrate behind the leading edge and erode the aluminum structure of the left wing which ultimately led to the breakup of the orbiter. The Columbia Accident Investigation Board (CAIB), a group of experts assembled to conduct an investigation independent of NASA concluded in August, 2003 that the cause of the loss of Columbia and its crew was a breach in the left wing leading edge Reinforced Carbon-Carbon (RCC) thermal protection system initiated by the impact of thermal insulating foam that had separated from the orbiters external fuel tank 81 seconds into that mission's launch. For the next several months an extensive investigation of the accident ensued involving a nationwide team of experts from NASA, industry, and academia, spanning dozens of technical disciplines.
On February 1, 2003, the Space Shuttle Columbia broke apart during reentry resulting in loss of seven crewmembers and craft.
0 kommentar(er)
