US Navy Carrier Strike Group 4 has been jamming the GPS on the Eastern Coast of the United States. The FAA has put out a NOTAM saying that eight of the FAA’s Air Route Traffic Control Centers, warns, GPS could be degraded from Caribbean and Florida north to Pennsylvania west to the eastern Louisiana can be affected. That’s over 2,800 airports home to over 28 thousand aircraft. This isn’t the first time the US has jammed GPS signals. AOPA wrote an interesting article on this which you can find here.
The Military jams it’s GPS to simulate war attacks and trains incase something like this ever happens. This is not a normal but is not unheard of the US Doing this.