Blog Editor’s Note: An excellent summary of where America has been with PNT resilience and policy and where it needs to go.

Interesting to note that the false rationale “GPS is expensive so we need to economize and have fewer other PNT sources” seems to have persisted from the 1980’s until today. It doesn’t help that the way the Department of Defense describes GPS III makes it sound like it will solve all the nation’s problems.

As the good book says, “The sins of the father shall be visited upon the children to the third and fourth generation.” Not a threat so much as a description of the way society works.

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Defense Matters

National PNT Infrastructure

Getting the U.S. on the Path to Resilience

Doug Taggart, President, Overlook Systems Technologies, Inc.

There is a dichotomy between our national space-based positioning, navigation and timing (PNT) policies and the decades-old recognition that overreliance on the Global Positioning System (GPS) as the single source for PNT leaves U.S. critical infrastructure vulnerable.

The May 2021 Colonial Pipeline computer hack serves as an all too recent example of how vulnerable Americans are to single-source supply chains. The hack, attributed to a group known as DarkSide, shut down 5,500 miles of pipeline, interrupting the flow of gasoline across the United States’ Southeast and MidAtlantic regions.

The ramifications of an intentional disruption of GPS have been theorized about and analyzed ad nauseum. Even if only one specific sector of our critical infrastructure was the primary target of a space-based PNT interruption, there would most certainly be collateral damage beyond the intended target.

We must find a way to get out of this unending refusal to address the reality of overreliance. Though national spacebased PNT policy dating back to the Bush era has highlighted the need for a backup to GPS, nothing has been done to date.

The 1984 Federal Radionavigation Plan’s (FRP) Executive Summary contained a passage that clearly conveyed the challenge of meeting the needs of all PNT users. “The goal [of the FRP] is to select a suitable mix of these common civil/military systems which can meet diverse user requirements for accuracy, reliability, coverage, operational utility, and cost; provide adequate capability for future growth; and minimize duplication of services. The process of selecting a system mix is a complex task, since user requirements vary widely and change with time.”