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GPS Problem Reports Status
GPS Problem Reports Status 2018

Civil GPS Users are encouraged to submit reports of GPS problems to NAVCEN. A form to submit reports can be found on our GPS Problem Reporting webpage. Some information from those reports is shared here along with input from interagency partners and the most likely cause of the report.

Descriptions for each of the fields is at the bottom of the page.

* Fields are as provided by the reporting source and are unedited.
*Date/Time of
Disruption
Date
Submitted
Location *Type Description Cause NAVCEN
Date Closed
08/29/2018    18:00 Middle East Time (+3:30) 09/12/2018 Tehran, Iran Communications Mobile phone clock synchronization problem. Unable to access internet, Waze, or other GPS applications.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
User Equipment 09/17/2018
09/07/2018    00:40 CET 09/06/2018 Bratislava, Slovakia Automobile Two different GPS tracking modules placed outside window cannot find GPS signal.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
Unknown Interference 09/10/2018
09/06/2018    1359 CST 09/06/2018 Gulf of Mexico Marine Multiple vessels in our area experienced degradation of GPS signal resulting in elevated PDOP. GLONASS systems were unaffected.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, they informed us that due to the current GPS constellation there is abnormally high DOP in the Gulf of Mexico. It is only for a short time.

Additionally, there was an authorized GPS tests in the vicinity at the date of the report. NOAA reported impacts to their equipment in the area. No other correlating reports from other users or interagency partner.
GPS Testing 09/10/2018
08/20/2018    1700 PST 08/21/2018 San Bernardino, CA Transportation GPS devices showing satellites with no lock.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.
User Equipment 08/30/2018
08/10/2018    00:40 Phoenix Standard Time 08/20/2018 Scottsdale, AZ Other Testing mixed mode tracking Y-code and M-code. Receiver lost lock on the L1 channel, L2 continued to track. Could track C/A, but not L1.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.
User Equipment 08/30/2018
08/11/2018    1605 China Taiwan Time 08/11/2018 50 miles from Qingdao, China Marine Military/navy exercises being conducted south of our position. Disruption at intervals for the last 50 mins. Receiver use: Input to nav equipment, communications. Vessel at anchor.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
Unknown Interference 08/30/2018
08/03/2018    11:30 EST 08/03/2018 Avon, IN Other My son wears a GPS watch due to the possibility of him wandering from school. Around 11:30 today, I received a “check in” notification that he was in Upland, IN. I called the school in Avon, IN (hours from Upland) and they confirmed he was in class.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.
User Equipment 08/30/2018
07/23/2018    1428 EST 07/24/2018 Port Said, Egypt Marine Vessel moored in Port Said Egypt when they lost the primary and secondary GPS. Disruption was intermittent. GPS also showed the ships location west of Alexandria on at least one occasion.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
07/04/2018    1500 EEST 07/04/2018 Port Said, Egypt Marine Vessel at anchor in Port Said, Egypt. GPS units started alarming with NO GPS FIX alarms. Position verified using anchor range and bearings & manually fixing position on ECDIS. Other vessels in area are reporting GPS problems as well. GPS interference continued intermittently throughout the entire day.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
07/04/2018    1500 EEST 07/04/2018 Port Said, Egypt Marine Vessel was at anchor in Port Said, Egypt awaiting a canal transit on the GPS units started alarming with NO GPS FIX alarms. We verified our position using our anchor range and bearings & manually fixing position on ECDIS. Other vessels in area are reporting GPS problems as well.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
06/28/2018    0600 CST 06/28/2018 Rockport, Texas The problem are the directions given to truckers, etc, when attempting to visit our facility. Directions send the vehicles to the south side of the ship channel. Our facility is on the north side of the ship channel. Mapping Issue 07/30/2018
06/28/2018    10:00 (Arabic) Egypt Standard Time (+2:00) 06/28/2018 Ankara, Turkey Other Product developer not getting valid fix. Tried to get a fix with cell and could not. The phone saw one satellite and it had a very weak SNR.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partner.
User Equipment 08/30/2018
06/15/2018    10:00 EST 06/24/2018 Powell, Ohio Transportation Mapping application showed GPS unavailable. Requests if there was an outage in the area.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partner.
User Equipment 08/30/2018
06/16/2018    11 Brazil Eastern Time 06/22/2018 Vila do Conde, Brazil Marine Every day in the morning time up to lunch time the GPS gives warnings about unsafe position.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
Unknown Interference 08/30/2018
06/15/2018    0730AM CST 06/15/2018 Nashville, Tennessee Other Mapping applications on three devices gave the wrong directions three times. None of the maps were anywhere correct. Was there a disruption or outage? Might not be anything but it was very odd. Also, the application seemed to be speaking jabberwocky at times during the ordeal of us being lost.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partner.
User Equipment 08/30/2018
05/26/2018    08:44 UTC 06/08/2018 Yellowknife, Canada  Other PRN18 failed to be measured near the period of an unusable (UNUNOREF) NANU covering part of the reported period. NANU 2018028-GPS SATELLITE SVN34(PRN18)WAS UNUSABLE ON JDAY 146 (26 MAY 2018) BEGINNING 0948 ZULU UNTIL JDAY 146 (26 MAY 2018) ENDING 0950 ZULU. IGS observations covered 0940-0948.
Report forwarded to GPSOC. Issue was covered by the release of NANU 2018028.
None 07/30/2018
05/01/2018    16:30 EST 06/04/2018 Doylestown, Pennsylvania  Communications Indicated location was erratic and device was unable to obtain accurate GPS location even after device was reset after traveling 5 miles. Device works normally in other locations throughout the U.S. Mapping Issue 07/30/2018
05/10/2018    0008 GMT 05/31/2018 Fairbanks, Alaska Other Since 10 May, several balloon flights have been terminated due to possible GPS interference issues. Analysis points to a possible disturbance source of narrow beam transmission from the airport or in its vicinity.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There was an authorized GPS tests in the vicinity at the date and time of the report. No correlating reports from other users or interagency partner.
Authorized GPS Testing is announced on NAVCENs website.
GPS Testing 08/30/2018
05/29/2018    14:00 Near East Time 05/30/2018 Le Port Reunion Island Surveying GPS elevation inaccuracy greater than 10 cm between 1400 and 1430 and then from 1800 local time (UT+4). It is affecting about 10 or more receivers on site (all machines, survey boat, land GPS backpack, excavators) we are working with RTK mobile receiver link to a base station by radio ling. There are three RTK base station on site with dedicated radio link. We saw on the sky GPS predictions. That GPS N29, is in view between about 1700 and 1430 then coming back again from about 1800 (5 degree elevation mask). We will try to disable GPS N29 from our equipment. No further information provided.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
User Equipment 08/30/2018
05/27/2018    0600 PST 05/27/2018 Bend, Oregon Automobile Getting a NO GPS symbol on our unit, tried resetting and powering on and off, no swings have changed since last use.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partner.
User Equipment 08/30/2018
05/18/2018    1730 (Arabic) Egypt Standard Time (+2:00) 05/18/2018 100NM off Port Said Marine For the past hour GPS signal is either lost or incorrect in approximately 5 minute increments. Vessels in the area are reporting the same.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
05/18/2018    1430 (Arabic) Egypt Standard Time (+2:00) 05/18/2018 35 NM North of Egyptian coast Marine GPS total signal loss on 3 occasions. Last noted GPS interruption was on 30 APR 2018.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
05/10/2018    0954 UTC 05/10/2018 Port Said, Egypt Marine Vessel is located in port, position keeps changing even though vessel is not moving. Position is wrong in about 2-2.5hr increments; incorrect positions are not consistent.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
05/09/2018    6:45 EST 05/09/2018 Armenia, Quindio, Columbia Other All my phones, my friends phones, and tablets are currently experiencing this outage in Armenis, Quindio, Colombia.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
Unknown Interference 08/30/2018
04/30/2018    11:00 EST 05/01/2018 Orlando, Florida Aviation Producer of high accuracy, aviation time, space, and position information equipment; develop, produce, and maintain equipment. We have been experiencing nearly continuous interference over the past two days. The interfering transmitter is operating in the range approximately 1566-1576 MHz. The signal is a modulated signal and appears to be an out of band transmitter as opposed to a jammer. We have captured the spectra at several times. The interfering system is blanking our (and presumably other) receivers. We are well versed in GNSS systems and technology. The ongoing interference is impacting our ability to conduct operations.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partner. Report forwarded to FCC for action.
Unknown Interference 08/30/2018
04/23/2018    8:30am Mountain Standard Time 04/25/2018 Colorado Springs, Colorado Going north on I-25 around Colorado Springs, CO., GPS insisted that I get off of I-25 at each exit instead of waiting for correct exit. It occurred entering and departing Colorado Springs, CO. area. Mapping Issue 07/31/2018
04/17/2018    11:00 EEST 04/18/2018 Romania and Vietnam Marine We have received reports from a shipyard in Romania and Vietnam having lost of GPS at a specific time of the day. In Romania, happens every day at 11:00 AM during about 5 minutes and in Vietnam happens at 3:00 AM or 1:30 PM depending of the position of the vessel. We would like to confirm that there are no known test/trials happening in this area at that specific time.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners. Recommended contacting the National Authority for Management and Regulation in Communications.
Unknown Interference 08/30/2018
04/18/2018    08:00 GMT 04/18/2018 EASTERN MEDITERRANEAN SEA Marine DISRUPTIONS EVERY FEW MINUTES, CONTINUING AT TIME OF NOTIFICATION. ALL VESSELS IN THE AREA ARE COMPLAINING ABOUT THIS ISSUE. NO GPS POSITION FROM MORE THAN 3HRS. SATELLITES ARE TRACKED AND DECLARED HEALTHY IN GPS RECEIVER BUT NO POSITION AVAILABLE. PLEASE ASSIST ACCORDINGLY.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
04/16/2018    1700 (Arabic) Egypt Standard Time (+2:00) 04/18/2018 Port Said, Egypt, N entrance of Suez Canal Marine Intermittent and very frequent loss of GPS signal (time and position) while vessel was approaching Port Said). Same was reported by many vessels in vicinity by VHF radio.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
11/06/2017    13:35:07 GMT 04/10/2018 Kume Island, Japan Marine At 13:35:07, the GPS time output jumped to 13:37:16. It remained constant with this time offset for 10.5 hours. At 00:03:37, it jumped backwards from the offset time to the correct time. It maintained this time afterwards. This is a mature installation. Clear sky view. Other GPS receivers in operation did not experience problems. Were there any constellation issues at that time? If not, can you postulate a fault mechanism that could cause a constant time offset like this? Note: Question 6 did not allow "2017" as the year the disruption stopped. User Equipment 07/31/2018
03/22/2018    0200 (Arabic) Egypt Standard Time (+2:00) 03/26/2018 DAMIETTA PORT, Egypt GPS EXPERIENCES LOSS OF SIGNAL PROBLEM FROM LAST 5 DAYS. MOST OF THE TIME IT HAPPENS NEAR EGYPT, LEBANON AND IN EASTERN MEDITERRANEAN REGION.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
03/21/2018    20:00 (Arabic) Egypt Standard Time (+2:00) 03/22/2018 AT SEA, POST DEP PORT SAID, Egypt Marine Master deemed it necessary to send it as non-routine under "any other potential, including potential problems" as the matter concerns vessels primary navigational system. Note that vessel had experienced problems with both GPS units of "no signal, alarm 001" since the night of 21st mar 2018. The problem of "no signal, alarm 001" was experienced on both GPSs just after departing from Suez Canal, Port Said side, on 21st Mar 2018. The problem was very frequently experienced in 3/O & 2/O watches. Then intermittently in C/Os watch going into the morning 22nd Mar 2018. Pls note that we had called at least 4 ships in our vicinity and they all confirmed the same problem with their GPSs, though with varying frequencies. This of-course has had an effect on the ECDIS. When the signals were lost, the courses went haywire. ARPAs was also effected, positions were not showing up.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
03/21/2018    0400 EEST 03/22/2018 Suez Marine Vessel is West bound from Port Said to Gibraltar. Position stated is current one, problem with GPS position started in Port Suez on 21 March. This is ocean going ship with 3 GPS units (all same model) with no prior problems. Overheard on VHF other vessels experiencing GPS position issues. Can you confirm if the area is affected by malfunction, testing or other disruptions of GPS system? I suspected hardware problem, but it happens on ALL units and position is on and off. Thank you.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
02/01/2017    0800 Mountain Standard Time 03/19/2018 Breckenridge, Colorado Automobile My GPS in this 2002 Vehicle worked until a few years ago, I have tried various working units with the same results. GPS signal good, clock and speed work, calendar currently reading July of 2015. Seems like this satellite is no longer updating correct info. Manufacturer can't help, vehicle dealer had me reset, always wrong date. I believe it has something to do with the satellite, but no one has any info on what satellite this might be. User Equipment 07/31/2018
03/19/2018    1100 EEST 03/19/2018 Cyprus Marine We have received information from multiple sources indicating a problem in receiving GPS signals on their equipment or having an accuracy problem, while sailing in the eastern Mediterranean. Could you please provide any information regarding this problem so we can promulgate relative messages in case necessary?
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 08/01/2018
01/01/2018    1100 AEST 03/19/2018 Southern Tasmania Marine Numerous high HDOP errors frequently occurring over previous 3 months. Our unit is set to alarm at HDOP>2.0, and the alarm has been sounding numerous times each day. Vessel operating in southern Tasmania region, within a 200 mile radius of the position given above. Occasional very high spike into HDOP>30, and 2 occurrences >100, with subsequent position shift of around 200 metres noticed on ECDIS. Backup GPS receiver also shows occasional high DOP error (not split into HDOP and VDOP), but not as high as main unit. Is this likely to be a receiver fault?

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
User Equipment 08/30/2018
03/18/2018    0600 EEST 03/18/2018 Port Said, Egypt Marine We have 4 DGPS and 3 GPS receivers on board. All of them affected. GPS were lost and DGPSs are being affected with not stable position or lost. Disturbance still continuous.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
03/07/2018    500 PST 03/07/2018 San Francisco, California Automobile Since 5am 7th March we noticed that the L1 frequency has been marked unhealthy in the CNAV ephemeris message. This is still continuing at 5pm on the same day. All L2 CNAV ephemeris message indicate that the L1 is unhealthy. Additionally L5 is marked unhealthy however this was the case before 5am today as well.
The L2C and L5 signals are considered pre-operational. A pre-operational signal means the availability and other characteristics of the broadcast signal may not comply with all requirements of the relevant interface specifications and should be employed at the user's own risk. Refer to Notice Advisory to NAVSTAR Users (NANU) 2014038 and 2014039.
User Equipment 07/31/2018
02/19/2018    04:42 UTC 02/27/2018 Washington (USA), Yellowknife (Canada), Brest (France) Other On the 19th of February 2018, some IODE/IODC of the ephemeris/clock information transmitted by PRN#06 from 04:42:30 to 06:44:30 were the same (14,15) as the data used on the same day for that PRN from 03:53:00 to 04:42:30 while the navigation data were different in violation of the GPS ICD 200 IODE repetition rule (unicity over 6 hours) and of the GPS ICD 200 IODC repetition rule (unicity over 7 days).
Response from GPS Operations Center: The cause of the IODC repetition error was the result of an issue experienced with the ground control system. The problem has been corrected.
ICD_Violation 07/31/2018
02/16/2018    1400 EST 02/16/2018 West Palm, Florida Marine No description provided.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
User Equipment 08/30/2018
01/31/2018    0700 UTC EEST 02/01/2018 Bad Pyrmont, Germany Timing This morning I was contacted by my colleagues who both have observed an anomaly in the timing characteristics of the GPS signal. One GPS receiver did an internal measurement against a Rubidium unit coupled with a very long time constant showed a time drift of -45ns an then back to zero whereas the other receiver is measuring the GPS offsets against its internal HQ OCXO showed a time drift of +150ns and then back to zero. Both have used different types of receivers. Is there a known anomaly in the GPS signal on Jan 31th between 7.00 and 8.00 UTC? We have checked the number of received satellites and have found no outage.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.
Unknown Interference 08/30/2018
01/08/2018    7:30 pm PST 01/25/2018 Hinkley,California Automobile Heading East on highway 58, near Hinkley, CA, the GPS in the navigation suddenly announced "off route and recalculating", when the map restored, it showed the vehicle to the north of highway 58. Over 5 miles it slowly moved back until it showed us back on the highway. we checked both our cell phones and they showed the same error. On our return trip on Jan. 16, the same error occurred going west on highway 58 also just west of Hinkley.
No correlating reports from other users or interagency partner.
Mapping Issue 08/02/2018

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Date / Time of Disruption: Date and time of the report as provided by the reporting source.

Date Submitted: Date the report was submitted to NAVCEN.

Location: The City and State location of the reported problem based on input from the reporting source. Latitude and longitude may be used for maritime reports.

Type: Installation type as provided by the reporting source. Choices include: Agriculture, automobile, aviation, communications, first responder, marine, law enforcement, research, surveying, timing, transportation, and other (with a fillable field).

Description: Description of the problem. This information from the reporting source is edited for clarity and to remove personal and equipment manufacturer identifying details. The description also provides constellation analysis information as provided by the GPS Operations Center, a determination if authorized GPS testing might have been a factor, and information on correlating reports from other users and interagency partners.

Cause: The most likely cause of the report based on interagency input.

NAVCEN Closed Date: NAVCEN collects interagency input and provides a detailed response to the reporting source for each report submitted. If there are no further questions from the reporting source, and NAVCEN has no other correlating information, NAVCEN will close the case. The results of interagency input will be included in the description field when the case is closed. This date may not correspond to the event end date.