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Audit Reports


FAA Operational and Programmatic Deficiencies Impede Integration of Runway Safety Technologies

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From fiscal year 2011 to fiscal year 2013, the number of runway incursions at U.S. airports increased by 30 percent, despite slight declines in air traffic operations during that time. To detect potential runway conflicts, air traffic controllers use the Federal Aviation Administration’s (FAA) Airport Surface Detection Equipment-Model-X (ASDE-X) at major airports. FAA has made runway safety a key oversight priority and plans to upgrade ASDE-X and integrate two runway systems with ASDE-X to improve safety: the Runway Status Lights (RWSL) system and the satellite-based Automatic Dependent Surveillance-Broadcast (ADS-B). We assessed FAA’s ongoing efforts to implement and integrate these surface surveillance technologies.

While FAA requires additional funding to upgrade and maintain ASDE-X’s current performance levels and meet anticipated increases in air traffic, FAA does not know how the upgrade process may affect ASDE-X’s performance. The RWSL program, which uses ASDE-X data, has experienced operational and technical issues, and FAA rebaselined the program last summer, significantly increasing costs, reducing the number of planned systems, and delaying program completion. Further, it remains unclear when or how ADS-B will enhance pilots’ situational awareness on the runway. Specifically, FAA has not determined whether it can provide pilots with ADS-B information displayed in the cockpit and has halted efforts to use ADS-B to provide pilots with direct alerts of potential ground collisions. Finally, FAA’s planning documents for implementing runway safety technologies lack key details on priorities, timing, and accountability. Without a clear roadmap, it will be difficult to achieve and measure a new level of technology or standard for runway safety.

We made three recommendations to aid FAA’s efforts to integrate surface surveillance technologies and promote runway safety. FAA concurred with two recommendations and partially concurred with one. We are requesting additional information for two of the recommendations.


Closed on
No. 1 to FAA
Develop and implement a plan, in coordination with airport authorities, to address issues, such as construction schedules and site adaptation/design that may impede RWSL's deployment within cost and schedule estimates.
Closed on
No. 2 to FAA
Develop and finalize timetables as to when ADS-B can be expected to impact surface surveillance systems through the use of moving map information in cockpit displays and surface alerts for pilots.
Closed on
No. 3 to FAA
Develop specific milestones for integrating ASDE-X, ASSC, RWSL, and ADS-B based on coordination between offices involved in runway safety; identify the offices accountable for achieving these milestones; and publish this information in the FAA National Runway Safety Plan.