Panel Finds No Serious Flaws to Delay Shuttle : However, Report by 12 Scientists Recommends Changes in NASA Risk Assessment Procedures
A scientific panel Friday proposed risk management procedures to “reduce the likelihood” of a catastrophe similar to the Challenger disaster but said it had found no problems serious enough to put off the resumption of space shuttle flights.
The 14-month study of National Aeronautics and Space Administration safety procedures “found absolutely no show-stoppers,” said Gen. Alton Slay, chairman of the National Research Council committee, as he presented the group’s 144-page report.
“Although we have criticisms, we did not find any flaws in NASA’s safety program serious enough to delay the next space shuttle launch, which is now set for August,” Slay told reporters.
Provides More Information
Asked if his oversight committee’s procedures could have averted the Jan. 28, 1986, Challenger disaster, which has been attributed to the failure of O-ring seals in unusually cold weather, Slay replied: “The only thing we can say for sure is if these procedures had been in place, we would have had more information at our fingertips.”
Asked if he thought NASA had taken a close enough look at the record low temperature prevailing at the time of the Challenger launch, Slay replied: “I think the record is very clear. . . . No, they did not take a close enough look at that.”
Emphasizing that “any kind of space travel will always entail risks,” Slay said “the key to minimizing those risks is to identify the most likely hazards or failures and to take steps to eliminate them or control them if they cannot be eliminated.”
The committee’s 12 members, a majority of whom are aerospace officials, recommended that NASA integrate more closely the procedures by which it assesses risks and undertakes to manage or control them; that it adopt more objective and mathematic standards for evaluating risks, and that it develop priorities for rating equipment failures “based on both the likelihood of a failure occurring and the probability that such a failure would lead to disaster.”
Work With NASA
Slay reported that his committee had worked closely with NASA officials, who have been “with us at every step” and have carried out many of the group’s recommendations.
The committee audit was set up by the National Research Council, which is the operating arm of the National Academy of Sciences, to verify the adequacy of a safety review of items “critical to mission success and flight safety” undertaken by NASA at the instance of the presidential commission on the Challenger disaster headed by former Secretary of State William P. Rogers.
The group’s intensive study showed, the report said, that NASA has “basic organizational elements for assessing and managing risk,” but it complained that a “complex mosaic of analysis techniques” impedes any unified view of safety problems.
NASA should develop procedures to identify and evaluate risks and then determine whether they are within acceptable levels, the report said. It criticized NASA for relying too heavily on “subjective judgments,” rather than statistical procedures.
Cites NASA Error
For example, the report said NASA fails to rely on “an integrated assessment of all inputs” in reaching decisions on whether to waive certain safety requirements because improvements are “not feasible.”
The committee recommended that NASA establish an integrated review process for risk assessments of equipment rated critical. At the same time, it recommended that priorities be established to rate the probability of failure of critical items.
Failures in some cases are “extremely unlikely,” it said, and treating all items equally detracts from the attention that should be given to “the most likely and most threatening failure modes.”
Stressing the need to base safety priorities for equipment on the probabilities of failure, the report called on NASA to increase its staff of specialists and engineers trained in statistical sciences to transform complex data in this area into information useful to decision makers.
