The Pentagon's growing stable of GPS backups is spread across too many separate service programs to stay on schedule, and the department should start merging them, the Government Accountability Office concluded in a report summarized in GAO's Oct. 7 reports feed. The finding lands on the Army, the Navy and the Department of the Air Force, each of which runs its own alternative positioning, navigation and timing (PNT) efforts, and on the contractors building receivers, satellites and integration kits for them. The report, GAO-27-107676, is titled "Precision Navigation Systems: Challenges Remain with Fielding New Capabilities."
GAO wrote the report under a provision Congress put in law requiring the watchdog to track DOD's GPS modernization and its development and fielding of complementary PNT systems. Its auditors reviewed program documentation and interviewed officials from DOD and the military departments.
Why GPS Modernization Delays Pushed the Services Toward Backups
GAO's summary opens with a blunt assessment: DOD's efforts to modernize GPS "continue to face delays." In response, the department is building new complementary sources of PNT data to blunt threats to the constellation.
The ground segment drew the sharpest language. "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," GAO wrote. Among other effects, GAO said, that decision "creates risks for the launch, checkout, and operation of new GPS satellites."
Air & Space Forces Magazine, which reported on the GAO findings Oct. 9, noted that today's constellation mixes new and legacy satellites, the oldest of which are nearly 30 years old, and that efforts to modernize GPS satellite, ground and user equipment "have faced repeated delays." U.S. leaders have warned in recent years about jamming and spoofing, and the Pentagon depends on space for precision targeting and communications.
Given those threats, GAO said DOD is operating and continuing development of three categories of capability: satellite-based PNT systems, non-satellite-based PNT systems, and backup timing solutions.
Who Is Building What: LEO Satellites, Celestial Receivers and M-Code
Every service now has a piece of the backup problem. According to Air & Space Forces Magazine, the Air Force, Space Force, Army, Navy and Marine Corps have all pursued programs to augment GPS or serve as a backup if the constellation is unavailable. The Space Development Agency and the Army are fielding PNT satellites in low-Earth orbit, and the Navy is developing a receiver that can calculate a ship's position without GPS by using stars, planets and satellites on predictable orbits.
On the user-equipment side, GAO reported mixed progress with M-code, the modernized, secure military GPS signal. The Air Force "continues to make progress developing modernized GPS military code (M-code) receiver cards, but challenges remain with fielding and integration," the summary states. The M-code aviation receiver programs in particular "continue to encounter development and integration challenges." The Navy is developing an interim solution so its aircraft can use M-code.
Ground and sea platforms are further along. GAO said the Army and Navy are fielding M-code capable and multi-PNT receivers in ground vehicles, ships and Army aircraft, and all the services are pursuing integration of complementary PNT data into multi-PNT receivers.
How Fragmented PNT Programs Could Strand M-Code Munitions
The core of the report is coordination. "Ineffective coordination of the fragmented interdependent PNT efforts among multiple military services—sometimes across more than one—hampers efficient alignment of those efforts," GAO says in its report, as quoted by Air & Space Forces Magazine. The summary adds that these alignment problems affect DOD's ability to ensure that M-code and PNT efforts "are completed promptly."
GAO's example involves munitions. If weapons gain an integrated M-code capability before the aircraft, ships and ground platforms that fire them, which GAO says is likely to occur, the mismatch could cause synchronization issues before and after launch, because positions are usually passed from a platform to a munition, Air & Space Forces Magazine reported.
Oversight structures have not closed that gap. Congress mandated a PNT Oversight Council to oversee the portfolio. GAO noted that while the council can make budget-related recommendations to the services, "the services are responsible for their own budgets," which leaves the council without direct control over the money that sets each program's pace.
What Consolidation Would Look Like for the PNT Portfolio
"The PNT enterprise could benefit from consolidating and aligning efforts among the services," GAO wrote. DOD has already taken one step in that direction, combining aircraft PNT receivers and M-code receiver card efforts into a single joint program office managed by the Air Force. GAO said benefits of further consolidation could include synchronized schedules and better strategic alignment of funding.
The report recommends that the Army, Navy and Department of the Air Force identify opportunities to consolidate complementary programs to "ensure better strategic alignment with DOD and the other services," according to Air & Space Forces Magazine. "These efficiencies may improve schedule alignments between interdependent programs and ease the realignment of resources for higher priority programs within the portfolio," GAO wrote.
What It Means for Contractors
Vendors working across the PNT portfolio should read GAO's recommendation as a signal that the current number of separate service programs may shrink. If the services follow through, firms that hold work on several overlapping efforts could see requirements folded together, schedules re-baselined, or funding shifted toward whichever programs the services rank as higher priority.
The joint program office model already in place for aircraft receivers and M-code receiver cards offers a template. Those two efforts now sit under a single Air Force-managed office, and further consolidation could extend that pattern to other parts of the portfolio.
Integration is the other pressure point. GAO's munitions example shows the risk of capabilities arriving out of sequence across platforms. Contractors on weapons, aircraft, shipboard and ground-vehicle programs should expect more scrutiny of how their M-code and alternative PNT timelines line up with the systems they connect to.
The cancellation of the Next Generation Operational Control System and the shift to modernizing the existing GPS Operational Control Segment also matter for space-segment and ground-segment suppliers. GAO said that change creates risks for launching, checking out and operating new GPS satellites, so suppliers on either side of that ground system should watch how the schedule risk is handled.
