Precision Navigation Systems: Challenges Remain with Fielding New Capabilities

What GAO Found The Department of Defense’s (DOD) efforts to modernize GPS continue to face delays. In response, DOD is developing new complementary sources of positioning, navigation, and timing (PNT) data to mitigate GPS threats. In 2026, after years of delays, DOD canceled the Next Generation Operational Control System ground control system and began modernizing the existing GPS Operational Control Segment.