GPS satellite outages are determined by the US Air Force using a Notice Advisory to Navstar Users (NANU). NANUs are categorized by their type and can represent forecasted, current or summary outages. See the full list of outage types on the CelesTrak website.
GPS satellite outages identified as current by the US Air Force. Current outage types are usually reserved for unscheduled outages.
There are no current outages at this time.
GPS satellite outages identified as predicted by the US Air Force.
There are no predicted outages at this time.
GPS satellite outages identified as historical by the US Air Force, occurring within the last month.
|PRN||SVN||NANU||Type||Outage start||Outage stop||Duration|
|20||51||2019114||FCSTSUMM||Jul 23, 2019 23:25:00||Jul 24, 2019 05:14:00||00d:05h:49m:000s|
|8||72||2019115||FCSTSUMM||Jul 24, 2019 15:26:00||Jul 24, 2019 18:59:00||00d:03h:33m:000s|
|18||34||2019116||UNUNOREF||Jul 25, 2019 15:40:00||Jul 25, 2019 15:41:00||00d:00h:01m:000s|
|18||34||2019120||UNUNOREF||Jul 26, 2019 15:32:00||Jul 26, 2019 15:33:00||00d:00h:01m:000s|
|26||71||2019121||FCSTSUMM||Jul 26, 2019 12:52:00||Jul 26, 2019 16:51:00||00d:03h:59m:000s|
|32||70||2019123||FCSTSUMM||Jul 29, 2019 16:51:00||Jul 29, 2019 20:27:00||00d:03h:36m:000s|
|24||65||2019127||FCSTSUMM||Jul 31, 2019 11:48:00||Jul 31, 2019 15:08:00||00d:03h:20m:000s|
|10||73||2019129||FCSTSUMM||Aug 02, 2019 14:52:00||Aug 02, 2019 18:39:00||00d:03h:47m:000s|
|3||69||2019130||FCSTSUMM||Aug 05, 2019 17:45:00||Aug 05, 2019 21:05:00||00d:03h:20m:000s|
|9||68||2019131||FCSTSUMM||Aug 07, 2019 13:41:00||Aug 07, 2019 17:01:00||00d:03h:20m:000s|
|17||53||2019132||FCSTSUMM||Aug 08, 2019 14:31:00||Aug 08, 2019 20:36:00||00d:06h:05m:000s|
|18||34||2019134||UNUNOREF||Aug 13, 2019 14:22:00||Aug 13, 2019 14:23:00||00d:00h:01m:000s|
|8||72||2019135||FCSTSUMM||Aug 16, 2019 08:25:00||Aug 16, 2019 14:13:00||00d:05h:48m:000s|
Last checked for outage data: 2019-08-23 05:22:52Z
GPS outages in a calendar format from AGI can be found here:
Historical GPS Outages can be found here:
The basics of how GPS works with some technical content.
How Long Can You Use an Almanac?
GPS position data is contained in almanac files. Learn how long you can use these for analysis.
Operational Considerations for Improved Accuracy with an IOC Galileo Constellation
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Long term prediction of GPS accuracy - Understanding the Fundamentals
Topics on prediction methods for GPS and how long GPS errors can be predicted. Starting from an understanding of the elements of prediction, including almanac use and ephemeris and clock errors, I look at the statistics of GPS position error predictions under various scenarios.
Statistical Analysis of Military and Civilian Navigation Error Data Services
This paper examines the difference between ephemeris and clock errors generated using civilian data versus those generated using military data. The different data sources result from civilian GPS receiver and military GPS receiver.