Can someone more familiar with the situation explain why they jam GPS at all? You'd think the vast industry around the military could replace actual jamming with training aids. Even if the bespoke training tools are expensive, I doubt they're as expensive as an airliner wandering in to an active missile range. Not to mention the economic disruption to air traffic throughput.
Remember, GPS is a military tool first. Civilians get to use it at the militaries discretion. They could turn the selective availability (which was turned off in 2000) back on and remove a lot of civilian accuracy. Maybe civilian pilots are the ones that need to training aids more than the military. It seems to me that they should be able to navigate without gps in a safe manner. Edit: fixed term for selective availa…
https://web.archive.org/web/20080113123316/http://pnt.gov/pu...
> In September 2007, the U.S. Government announced its decision to procure the future generation of GPS satellites, known as GPS III, without the SA feature. Doing this will make the policy decision of 2000 permanent and eliminate a source of uncertainty in GPS performance that has been of concern to civil GPS users worldwide for some time.