contributing to their errors.9 Both ASAPs and ASRS allow for voluntary reports initiated by pilots and others in the aviation system, and both systems provide some degree of immunity from regulatory action or civil fines. These reports can play a valuable role in understanding and improving aviation safety. However, because they are based on voluntary reporting (resulting in a nonprobability sample; see Chapter 3 for a discussion of types of samples), they do not provide a means to develop statistically valid metrics of aviation safety.

Around the same time that NAOMS was developed, the Flight Operational Quality Assurance (FOQA) program was started by several airlines in the mid- to late 1990s. Through their FOQA programs, airlines gather selective digital data from flight data recorders installed on their airplanes and then process and analyze those data to identify particular events. These data can provide extensive information about flight operations. Unlike ASRS and ASAP reports, FOQA data can be available from all flights on all properly equipped airplanes. Unfortunately, these data are not currently available for all segments of the NAS. Flight data recorders are typically not installed on general aviation airplanes, and some operators who do have airplanes with appropriate flight data recorders may not have the resources to gather, process, and analyze those data. However, both recent and future advances in computer and data-storage technology may well reduce the cost of both collecting and analyzing such digital data. It may also become easier to integrate FOQA data with other data sources such as air traffic control data from FAA’s Operational Error Detection Program. FOQA data are limited, however, in that they do not reveal the intentions of the pilot during the recorded events, so they may provide an incomplete picture of the event.

More recently, FAA has launched the Aviation Safety Information Analysis and Sharing System (ASIAS). This system is housed and managed at the MITRE Corporation and contains both aviation safety and operations data and a collection of studies of specific aviation safety topics. ASIAS is designed to enable users to perform integrated inquiries across multiple databases, search an extensive warehouse of safety data, and display pertinent elements in an array of useful formats. ASIAS contains both the data sets and the query tools that allow easy access to the data.10

ASIAS is being developed in a phased approach. One can already access an array of aviation safety databases, including FAA Accident/Incident Data Systems, the Air Registry, the ASRS, Bureau of Transportation Statistics, the Near Midair Collision System, the NTSB Aviation Accident and Incident Data System, NTSB Safety Recommendations to the FAA with FAA Responses, and the World Aviation Accident Summary.11 Additional databases planned for inclusion in ASIAS include ASAP data, FOQA data, and other data.12 (A variety of other data sets are also available to the FAA and to safety analysts that are not included or planned to be included in ASIAS.)

The use of statistical techniques to extract pertinent information from currently available data is an attractive approach, as it takes advantage of information that is already available. However, extracting, combining, analyzing, and understanding data from diverse sources involves many challenges. MITRE and others are working to develop additional tools to extract information from ASIAS data.

All of the currently available data sources have their advantages and limitations. ASIAS has made considerable progress in allowing a wide variety of these databases to be easily accessed and integrated. If ASIAS continues to be developed as planned, it can become an even more useful source of data for the entire aviation system.


See FAA, Advisory Circular 00-58, Washington, D.C., May 4, 1998, available at$FILE/AC00-58.pdf, accessed July 15, 2008.


FAA, Aviation Safety Information Analysis and Sharing (ASIAS) System, Washington, D.C., available at,398034,56_398041&_dad=portal&_schema=PORTAL, accessed May 16, 2009.




FAA, National Aviation Research Plan (NARP) Appendices, Washington, D.C., February 4, 2008, available at, accessed July 15, 2009; and Victoria Cox, Statement before the House Committee on Transportation and Infrastructure, Subcommittee on Aviation, March 18, 2009, available at, accessed July 15, 2009.

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