GPS can improve transportation safety including aiding emergency response, but is vulnerable to interference from radio signal jamming or other sources. The Department of Transportation (DOT) is responsible for identifying GPS interference incidents and improving the transportation sector’s ability to withstand and recover from them.
A review by the Government Accountability Office (GAO) has found that DOT’s process for identifying incidents doesn’t produce accurate or complete information and isn’t documented. Also, GAO found that DOT has efforts underway to improve the sector’s resilience, like researching potential GPS backups, but it does not yet have a strategic plan to guide and prioritize these efforts.
Unintentional and intentional interference from a variety of sources such as solar flares and jamming can affect transportation safety. In January 2020, DOT began analyzing user reports of potential GPS interference across all transportation modes to identify incidents and support federal investigations. Through this process, DOT identified 196 potential GPS interference incidents from January 2020 through May 2022. However, GAO found that DOT’s process does not include all available user reports, and DOT’s data contain inaccurate information. For instance, GAO found that during this period users submitted 72 reports of potential GPS interference to a system DOT does not consider in its process. GAO determined that DOT’s process faces limitations because DOT has not documented it nor identified controls to ensure complete and accurate information. Instead, one individual knows how it works, and no other staff review or verify the results. The watchdog fears that without a process that produces quality GPS interference information, federal efforts to quickly respond to and stop interference could be delayed.
GAO pointed out in its December 15 report that DOT has undertaken many efforts intended to improve the transportation sector’s resilience to GPS interference, such as working to identify potential GPS backups. However, the extent to which DOT’s efforts have improved resilience is unclear because DOT has not taken a strategic approach to guide its efforts. Though DOT has taken steps to plan some of its resilience activities, DOT’s current approach does not guide its collective resilience efforts or fully define objectives, prioritize actions, or address challenges, consistent with key program management standards. DOT officials told GAO they are in the process of developing a strategic plan to guide its positioning, navigation, and timing resilience efforts but do not expect the draft to be complete until early 2023.
GAO recommends that DOT document its incident identification process, including identifying controls to obtain complete and accurate information and develop a strategic approach to resilience that fully aligns with key standards for program management. DOT agreed with these recommendations.