Data on air safety vague
NASA releases the airline data but scrambles it, leaving an unclear picture.
Published January 1, 2008
NASA grudgingly released some results Monday from an $11.3-million federal air safety study it previously withheld from the public over concerns it would upset travelers and hurt airline profits. The data reflect hundreds of cases where pilots flew too close to other planes, plunged from altitude or landed at airports without clearance.
NASA published the findings - contained in 16,208 pages - but did not provide a roadmap to understand them, making it cumbersome for any thorough analysis by outsiders. The unprecedented research conducted over nearly four years relates to safety problems identified by about 25,000 commercial pilots and more than 4,000 private pilots interviewed by telephone.
The results from commercial pilots appeared to reflect in part at least 1,266 incidents in which aircraft flew within 500 feet of each other, generally considered a near-miss; at least 1,312 cases where pilots suddenly dropped or climbed inadvertently more than 300 feet in flight; and 166 reports of pilots landing without clearance at an airport with an active control tower. The Associated Press matched the data to the questionnaire that was used to interview pilots and was obtained separately by the AP.
Because NASA scrambled and redacted the data, it was impossible to determine whether multiple pilots might be reporting the same incidents.
The data that NASA released was "intentionally designed to prevent people from analyzing the rates properly," said Jon Krosnick, a Stanford University professor and survey expert who helped design the project for NASA. He urged NASA to release more of the data needed for an analysis.
Citing people familiar with the research, the AP reported earlier that the data showed events like near-collisions and runway interference occur far more frequently than previously recognized.
The data were based on interviews with about 8,000 pilots per year from 2001 until the end of 2004. NASA Administrator Michael Griffin said Monday the survey was poorly managed and told reporters the traveling public shouldn't care about the data.
Louis Miller, executive director of Tampa International Airport, said he had not had a chance to sort through the pile of data to see if it has any implications for airport operations. He expected airports, airlines and air safety regulators would thoroughly review NASA's information.
"We take safety very seriously," Miller said.
NASA's survey, the National Aviation Operations Monitoring System, was intended to see whether it could help identify problems and prevent accidents. Survey planners said it was unique because it was a random survey with an 80 percent response rate and it did not rely on pilots to voluntarily report safety incidents.
Times staff writer Asjylyn Loder contributed to this report.
On the Web
To read NASA's documents from the National Aviation Operational Monitoring Service project, go to www.nasa.gov.
[Last modified January 1, 2008, 00:00:05]
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