ICS Alert (ICS-ALERT-11-024-01)

Federal Aviation Administration GPS Advisories

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The US Federal Aviation Administration (FAA) has issued two Flight Advisories identifying planned Global Positioning System (GPS) temporary outages and the affected areas. The Department of Defense will conduct the testing. During testing, the GPS signal may be unreliable or unavailable. ICS-CERT is issuing this alert to Industrial control systems (ICS) owners and operators using GPS for timing reference or positioning data to alert them regarding possible intermittent GPS service during the testing. ICS-CERT has contacted the FAA to obtain more information and details.

Flight Advisory GPS Testing CHLK GPS 11-06

Location: Porterville, CA1
Date: January 16th through January 23, 2011.
Affected Frequencies: M1575.42 and 1227.60
Duration: Tests will be conducted in several 15-minute blocks randomly spread over the testing hour.

Flight Advisory GPS Testing CSFTL GPS 11-01

Location: Brunswick, GA2
Dates: January 20 through February 11, 2011; February 15 through February 22, 2011.
Affected Frequencies: not identified.
Duration: Several test events will be conducted; each test will be active for 45 minutes followed by 15 minutes of off time.

  • 1FAA, “Flight Advisory GPS Testing CHLK GPS 11-­‐06 16-­‐23 January 2011 Porterville, CA”, http://www.faasafety.gov/files/notices/2011/Jan/Flight advisory porterville GPS.pdf, website last visited January 24, 2011
  • 2FAA, “Flight Advisory GPS Testing CSFTL GPS 11-­‐01 January 20-­‐February 11, 2011 February 15-­‐February 22, 2011 Brunswick, GA”, http://www.faasafety.gov/files/notices/2011/Jan/GPS Flight Advisory CSFTL11-­‐ 01 Rel.pdf, website last visited January 24, 2011

Contact Information

For any questions related to this report, please contact the CISA at:

Email: CISAservicedesk@cisa.dhs.gov
Toll Free: 1-888-282-0870

For industrial control systems cybersecurity information:  https://us-cert.cisa.gov/ics 
or incident reporting:  https://us-cert.cisa.gov/report

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