I’m not entirely sure what you are talking about, but most backup systems are Plane based.
GPS is mostly used for something called RNAV, however, RNAV can work without GPS. RNP approaches need GPS, but all airports (regardless how small, because without it would only be an airfield) have different approaches for both pilots and ground personnel to choose from.
GPS always has the possibility to fail, for the simple fact that the US military can just turn if the civilian frequencies. GPS is more or less an addition and not a crucial system (except for GPWS - while most planes have radar altimeters, they can’t react fast enough in some cases)
For those interested, here’s a Video where GPS gets jammed and there’s an explanation on what they do and what happens, when it gets spoofed https://www.youtube.com/watch?v=4dG_Whxzdkk
the US military can just turn if the civilian frequencies.
If you’re talking about selective availability, that’s basically gone. It started getting phased out by Clinton in 2000 and newer satellites don’t even have that capability.
My understanding IFR is completely (or mostly?) without GPS, and uses plane-based instruments for direction, heading, speed, altitude, anything else? And like ground-based radio objects, such as localizers, I don’t know the terms or if there are multiple systems?
I’m not entirely sure what you are talking about, but most backup systems are Plane based.
GPS is mostly used for something called RNAV, however, RNAV can work without GPS. RNP approaches need GPS, but all airports (regardless how small, because without it would only be an airfield) have different approaches for both pilots and ground personnel to choose from. GPS always has the possibility to fail, for the simple fact that the US military can just turn if the civilian frequencies. GPS is more or less an addition and not a crucial system (except for GPWS - while most planes have radar altimeters, they can’t react fast enough in some cases)
For those interested, here’s a Video where GPS gets jammed and there’s an explanation on what they do and what happens, when it gets spoofed https://www.youtube.com/watch?v=4dG_Whxzdkk
If you’re talking about selective availability, that’s basically gone. It started getting phased out by Clinton in 2000 and newer satellites don’t even have that capability.
Didn’t know that - i always thought all GPS sats have the ability to encrypt the signals…
Can you dumb that down a tad for me?
My understanding IFR is completely (or mostly?) without GPS, and uses plane-based instruments for direction, heading, speed, altitude, anything else? And like ground-based radio objects, such as localizers, I don’t know the terms or if there are multiple systems?
Highly depends on the approach. IFR can be a lot of stuff. All systems can be used at once as well (And in many cases, they are used all together)