[TheOtherCliff]

https://news.slashdot.org/story/16/06/07/205233/faa-warns-of-gps-outages-this-month-during-mysterious-tests-on-the-west-coast
http://gizmodo.com/faa-warns-of-gps-outages-this-month-during-mysterious-t-1780866590
https://www.faasafety.gov/files/notices/2016/Jun/CHLK_16-08_GPS_Flight_Advisory.pdf