Depends on the weather. A lot of approaches to airports are GPS only these days. If GPS doesn't work and you are not in VFR weather, you can't fly those approaches. In bad weather you'd be diverting to an airport that still has ILS.
Vectoring by the controller to a visual or ILS approach still works but they'd be juggling a lot of planes. And while lots of the bigger/older airports still have ILS, many VORs and DMEs are being retired and many smaller airports don't have ILS at all.
Denied access to GPS in a large area in bad weather would likely result in lots of flight cancellations and contingency plans getting put in motion to get anything still in the air landed safely. But controllers would get very busy and ILS runways very congested.
Here in Europe, there have been a few cases of GPS denied areas especially closer to Russia. Mostly pilots and controllers at e.g. Helsinki airport are able to deal with this.
Vectoring by the controller to a visual or ILS approach still works but they'd be juggling a lot of planes. And while lots of the bigger/older airports still have ILS, many VORs and DMEs are being retired and many smaller airports don't have ILS at all.
Denied access to GPS in a large area in bad weather would likely result in lots of flight cancellations and contingency plans getting put in motion to get anything still in the air landed safely. But controllers would get very busy and ILS runways very congested.
Here in Europe, there have been a few cases of GPS denied areas especially closer to Russia. Mostly pilots and controllers at e.g. Helsinki airport are able to deal with this.