GNSS interference is a common topic nowadays. In certain regions pilots are confronted with GNSS interference everyday or even every flight.
GPS jamming (most commonly encountered) is where the GNSS signals are interfered with, causing the receiver to lose it’s position, GPS spoofing is where the a faulty position is send to the GPS receiver, causing a map shift and or time shift.
With jamming the receiver is dying, with spoofing the receiver is lying.
Eventhough becoming quite common and pilots knowing how to deal with them, it still causes a threat to aviation. Especially those aircraft not equipped with DME / DME updating and IRS.
Maybe this could be simulated? There are tools and maps tracking areas of GNSS interference:
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It seems like all those places are connected in some way to military confict zones.
Don’t military and and commercial GPS use different systems?
Are some bad actors actively interfering with commercial and GA GPS?
Nope, it is the same system in both cases. I know, because the region I fly regularly in and out off we experience GNSS interference every single flight.
Not just conflict zones, northern / eastern Europe GNSS interference is very common. Finland, Poland, Baltics etc.
OK, thanks. How does the difference in precision work then? Does it have to do with the receiver’s capabilities?
As far as the areas you mentioned, I would call them “conflict zones”, meaning they are very close to NATO borders. 
Don’t think the countries in question would like to be called “conflict zones”, I live in one 
. There is a special code (P-code) that is encrypted and only for authorized users. But yeah, jamming / spoofing affects both.
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The Inibuilds a350 has an option for simulation of GNSS jamming.
I haven’t tried it.
The effects of GNSS jamming and spoofing on aircraft systems are quite complicated - jamming may not necessarily result in GNSS denial - dependent on jammer power and distance from jammer there is a grey area where signal strength is degraded and this can lead to odd things going on in the receiver - and in dependent systems - and there are a few…
Also often neglected is that many systems may utilise precision time from GNSS so you can get unexpected systems failing - which can be an unpleasant surprise…
Airbus have published a good article on the effects of RFI (radio frequency interference) on GNSS along with recommendations for operating flight crew - well worth a read for anyone interested..
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Yes, it doesn’t always affect all receivers at the same time, things like ADS-B and GPWS (enhanced part) could intermittently drop offline along with associated master cautions.
Spoofing could cause time shifts, causing CPDLC messages timing out instantly upon receiving them. Position shifts could cause GPWS FLTA to activate. ELTs with Distress Tracking could trigger.
Manufacturers haven’t really considered this threat when they designed avionics, some IRSs receive position updates from GPS which might knock them out as well, for DME / DME updating the aircraft needs to have a rough idea where it is, if position shifts a lot it might not tune stations in range.
I used to fly an aircraft type which could detect discrepancy between GPS and DME-DME position, but it would only create a caution if GPS has already been deselected as a FMS position source, which is quite useless therefore for detecting spoofing 
.
Best solution is to deselect GNSS before entering an area where spoofing is common. It is part of daily life in some areas.
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This is all very interesting (and new to me.) Thanks for the details.
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