Federal auditors say an experimental web-based method of surveying pilots to identify predictors of airline accidents, which took 10 years to develop, does not adequately represent the wider population.
The project, the National Aviation Operations Monitoring Service, was started by NASA in 1997 to evaluate the feasibility of using surveys to monitor trends in aviation safety.
"Although potentially useful for historic analysis, these data are limited in their ability to provide insight into the current health of the [national airspace system]," according to a Government Accountability report published Thursday.
While the design and deployment were well-intentioned and robust in many respects, the government would have to conduct a new survey to get the answers it was after, the report concluded.
Design decisions to protect pilot confidentiality and limited sample size hindered the survey's ability to account for operational differences across various-sized aircraft and the possibility that multiple pilots witnessed the same event, GAO said.
If officials were to try again, "researchers might reconsider the balance between confidentiality and the potential benefits of a questionnaire that allowed pilots to link reported events to particular aircraft and to identify aircraft they flew as air carrier pilots and in other capacities," the report stated.
The project was terminated at the end of its first and only decade, when NASA transferred an Internet-based version of its data to the Air Line Pilots Association (ALPA) in January 2007.
"Where hope had been that the . . . project would provide a comprehensive, systemwide, statistically sound survey mechanism for monitoring the performance and safety of the overall [national airspace system], ALPA did not plan to permanently implement the air carrier pilot survey as it was designed," the report stated. "The data collection system was never fully implemented, and its future is uncertain."