The Maritime Administration (Marad) posted an advisory Sept. 22 that multiple instances of significant GPS interference have been reported worldwide in the maritime domain. This interference is resulting in lost or inaccurate GPS signals affecting bridge navigation, GPS-based timing, and communications equipment.

Satellite communications equipment may also be impacted. Over the last year, areas from which multiple instances have been reported include the eastern and central Mediterranean Sea, the Persian Gulf, and multiple Chinese ports. The U.S. Transportation Command “Message for Industry” at https://go.usa.gov/xdSpq provides additional GPS interference information.

The advisory said to exercise caution when operating underway and prior to getting underway. The Coast Guard Navigation Center (NAVCEN) and NATO Shipping Center websites contain information regarding effective navigation practices for vessels experiencing GPS disruption. The information reaffirms safe navigation practices when experiencing GPS disruptions, provides useful details on reporting disruptions, and is intended to generate further discussion within the maritime community about other disruption mitigation practices and procedures. This guidance also recommends reporting such incidents in real time; noting critical information such as the location (latitude/longitude), date, time, and duration of the outage/disruption; and providing photographs or screen shots of equipment failures experienced to facilitate analysis. The NAVCEN information is available at: https://go.usa.gov/xQBaU.

Contact Information: Maritime GPS disruptions or anomalies should be reported immediately to the NAVCEN at https://go.usa.gov/xQBaw or via phone at 703-313-5900, 24-hours a day. NAVCEN will further disseminate reported instances of GPS interference in this region to the NATO Shipping Center.

This message will automatically expire on March 21, 2021.

For more information about U.S. Maritime Alerts and Advisories, including subscription details, please visit http://www.marad.dot.gov/MSCI.