First hearing on the Shuttle Columbia accident
On 1 February 2003 the Space Shuttle Columbia disintegrated in flames over Texas whilst making a hypersonic re‑entry into the Earth’s atmosphere. Its altitude and velocity were much higher than those flown by conventional aircraft .
Audrey T. Leath from the American Institute of Physics reported on the first Hearing on Shuttle Columbia Accident:
On February 12, the Senate Commerce, Science and Transportation Committee and the House Science Committee came together for the first of many hearings on the Space Shuttle Columbia tragedy and its ramifications. “Today we are focusing on the Columbia,” Senate Commerce Chairman John McCain (R‑AZ) noted. “At subsequent hearings, we will address the role of manned and unmanned space exploration, the costs and benefits of continuing the shuttle program and our investment in the International Space Station, and the effectiveness of NASA management. More fundamentally, we must examine the goals of our space program. We also must examine the extent to which Congress and the Administration may have neglected the shuttle safety program,” McCain acknowledged. “I view this hearing as the start of a very long conversation we will all be having about the Columbia incident and its ramifications,” added House Science Chairman Sherwood Boehlert (R‑NY).
Many House and Senate Members questioned NASA Administrator Sean O’Keefe during the four‑hour joint hearing. As the Columbia Accident Investigation Board, headed by retired Navy Admiral Hal Gehman, had just begun its work, the primary focus of the hearing was not on the cause of the Columbia accident. Instead, many of the questions addressed the composition and independence of the Accident Investigation Board. “I’ve become convinced that the Board’s charter must be rewritten,” Boehlert stated, expressing a concern that was echoed by other Members throughout the hearing. “The words of the charter simply do not guarantee the independence and latitude that both the Administrator and the Admiral have sincerely promised.” O’Keefe explained that a description of the investigation panel had been written into the accident contingency plan developed by NASA following the Challenger incident, but he expressed willingness to modify the Board’s charter and responsibilities to mollify Members’ concerns about its objectivity. “You have our assurance that this distinguished Board will be able to act with genuine independence,” he declared. Sen. Maria Cantwell (D‑WA) asked whether there was an independent scientist on the panel to provide “that Feynman voice” – a reference to the role played by physicist Richard Feynman during the Challenger accident probe. O’Keefe replied that Gehman was considering several scientists for addition to the Board.
Other major lines of questioning revolved around the age and role of the shuttle fleet, the impact of grounding the fleet on the space station, the amount of science performed on the shuttle and station, and the value of manned versus unmanned space flight. Addressing questions about whether the shuttle’s age was a factor in the accident, O’Keefe admitted that Columbia was “the oldest of the four orbiters,” but said it had recently been upgraded with new technologies, and that NASA had done everything possible “to ensure that age was not a factor.”
O’Keefe also pointed out that NASA had proposed an Integrated Space Transportation Plan that was intended to address the concerns of using the shuttle for both crew transport and cargo capacity. The plan, he said, would focus near‑term investments on extending the shuttle’s operational life and providing new crew transfer capability as soon as possible, and, for the long term, would develop next‑generation reusable launch vehicle technology.
Regarding impacts on the space station, O’Keefe reported that, since the Columbia tragedy, a Russian unmanned Progress resupply vehicle had delivered supplies to the crew as planned, and additional Progress and Soyuz flights would take place as scheduled. This would allow normal station operations, including research, to continue through June. While the station had sufficient propellant to maintain its orbit for at least a year without shuttle support, if the shuttle fleet was not operating again by June, he said, additional resupply flights might be needed to provide the crew with enough water. He also indicated that it would not be feasible for an autonomous resupply vehicle like Progress to bring up the next scheduled science experiments, so an extended grounding of the shuttle fleet would result in a “diminution of the science” being performed aboard the station.
Declaring that “we want science to be done in space,” Rep. Anthony Weiner (D‑NY) inquired whether the shuttle had been used less for science missions than as a delivery vehicle, “a UPS truck” for the space station. The shuttle’s cargo has included both portions of the station for assembly and scientific experiments, O’Keefe responded. He said most of the “groceries” were sent up on unmanned resupply vehicles, which could not be used to transport the science experiments. Members repeatedly expressed their support for a strong science program in space; O’Keefe cited the various kinds of research being conducted aboard Columbia at the time of the tragedy, and on the space station, including human physiology, genetics, biology, fire suppression, earthquake resistance, and Earth observations. To Rep. Lamar Smith’s (R‑TX) question, “Can we justify decades of repetitive shuttle flights to a space station that’s not met expectations?” O’Keefe responded, “In contrast to your characterization, we are spending a lot of time on science, as we transition from the engineering phase to science.” He indicated support for going beyond the planned US core complete station configuration as he continued, “It does take at least two folks to maintain [the station], but as we are able to expand the crew, and reach the configuration that enables full use of the station’s capacity, I think you will see comparable scientific results to those from the Hubble Space Telescope.”
Reports by NASA advisory and review committees raising warnings about the shuttle fleet’s age and continued safety were cited by many members. O’Keefe stated that the concerns raised were all in reference to future safety, but there had been no indications that the current safety of the shuttle program was compromised. Another issue raised repeatedly was the budget cuts made over the past decade to planned shuttle upgrades. O’Keefe explained that, in his understanding of the shuttle’s budget history, quality assurance procedures and other program management approaches had yielded efficiencies and cost reductions, while at the same time, indicators showed safety improvements and a decrease in safety incidents both before and on orbit.
Addressing questions about the justification of manned space exploration versus robotic, O’Keefe said it was “not an issue of either/or” NASA’s approach, as it was doing with the Mars mission – to use robotic capabilities to understand the risks of human involvement and learn what would be necessary to support an eventual human mission “if it is deemed appropriate.” He mentioned the Hubble Space Telescope as an example of how unmanned exploration capabilities and human involvement worked in a complementary way to achieve outstanding science.
“This is not the beginning of the end; it is the end of the beginning,” Boehlert said in conclusion. He praised the openness and cooperation of O’Keefe and Admiral Gehman, and “the total commitment I find on the part of every person involved… to get the facts and let us be guided by the facts.”
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