All of the U.S. military services are pursuing capabilities to complement GPS amid concerns that the constellation is increasingly vulnerable to interference, but a new government watchdog report calls for better coordination and prioritization among those efforts to avoid delays and duplication.
Today’s GPS constellation is a mix of new and legacy satellites, the oldest of which are nearly 30 years old. The system has become essential to the entire global economy, affecting industries like agriculture, banking, and transportation, which are dependent on the system for timing and positioning. It’s also a fundamental military capability, particularly important for navigating in remote areas and helping guide missiles and drones.
In recent years, U.S. leaders have sounded the alarm about GPS vulnerabilities, especially jamming and spoofing. Because the Pentagon is dependent on space for precision targeting and communications, signal disruption poses a growing threat. Efforts to modernize GPS satellite, ground, and user equipment have faced repeated delays, exacerbating those concerns.
The Air Force, Space Force, Army, Navy, and Marine Corps have all pursued programs to either augment GPS capabilities or serve as a backup should the constellation be unavailable. For example, the Space Development Agency and the Army are fielding positioning, navigation, and timing, or PNT, satellites in low-Earth orbit, and the Navy is developing a PNT receiver that can calculate a ship’s position without the use of GPS using celestial bodies like stars, planets, and satellites on predictable orbits.
While these efforts have seen various degrees of success, an Oct. 7 report from the Government Accountability Office highlights risks within the current GPS modernization plans and the services’ various alternative PNT pursuits.
“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. “Pursuing modernized GPS and complementary PNT technologies to augment GPS requires foresight and planning. Integration timelines for weapon systems are often lengthy, and schedules must be properly aligned for the development of such modernized PNT technologies and their integration into weapon systems.”
As an example, GAO points to efforts to upgrade munitions to use M-code, a specialized, secure GPS signal. If the munitions have an integrated M-code capability before the aircraft, ships and ground platforms that fire them—which GAO says is likely to occur—that could cause synchronization issues before and after launch since positions are usually passed from a platform to a munition.
The report notes that officials has made some steps to consolidate PNT development efforts into joint program offices but argues more is needed. The agency recommends 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” and drive efficiency.
“These efficiencies may improve schedule alignments between interdependent programs and ease the realignment of resources for higher priority programs within the portfolio to ensure that warfighters obtain these necessary capabilities to address current and future threats,” GAO writes.
