Installing new Global Positioning System (GPS) receiver cards on more than 700 different weapons systems will cost billions of dollars more than the Department of Defense’s estimate of $2.5 billion through fiscal year 2021, according to a new report by the Government Accountability Office (GAO).

DoD’s estimate reflects the existence of full or partial funding for only 100 of the 716 weapon systems that need new cards, the GAO wrote in its Dec. 12 report to Congress.

An artist's rendering of a GPS III satellite. Photo: Lockheed Martin.
An artist’s rendering of a GPS III satellite. Photo: Lockheed Martin.

“The cost will increase by billions when as yet unfunded weapon systems are included,” the report says. As a result, DoD and Congress “do have not visibility” into exactly how much additional funding will be needed.

Receiver cards use navigation signals from GPS satellites to calculate a warfighter’s location. The new cards will allow weapon systems to take advantage of M-code, a new, more powerful and more secure military signal provided by GPS III, the Air Force’s latest generation of GPS satellites. The first of those satellites is scheduled to launch in May.

The Air Force’s Military GPS User Equipment (MGUE) program and contractors L3 Technologies [LLL], Raytheon [RTN] and Rockwell Collins [COL] are developing the initial M-code-capable receiver cards for aircraft, ground vehicles and ships. Offices that upgrade weapon systems will further develop and test the cards.

To avoid duplicating effort on the new cards, the GAO recommended that DoD assign an organization to collect and share test data, lessons learned and design solutions. Responding to a draft of the report, DoD said it agreed with the suggestion.

The lead platforms for the new cards are the Army’s Stryker ground combat vehicle, the Air Force’s B-2 bomber, the Marine Corps’ Joint Light Tactical Vehicle (JLTV) and the Navy’s Arleigh Burke-class DDG-51 destroyer.

Weapon systems will need almost 1 million new cards. Until those systems get their new cards, they will continue to use their existing ones, such as the GPS Selective Availability/Anti-Spoofing Module (SAASM). Transitioning all platforms to the new cards is expected to take more than a decade.

The new cards will initially range in size from about 2 inches by 3 inches for ground vehicles to up to 6 inches by 6 inches for aircraft and ships. By March, the Air Force plans to develop an acquisition strategy for more compact receiver cards, an effort called MGUE Increment 2.