Originally Posted by silvertate
>>RAIM outages.
RAIM is real-time monitoring of the satellite constellation. You cannot determine RAIM outages by NOTAMS. Or are you telling me that the NOTAMS know exactly when the next satellite will be hit by some space debris, or lose its IRS stability system?
Wait what? So what exactly is this RAIM prediction feature that the local airways services outfit provides on it's web based flight planning/NOTAM service all about then? Or for that matter, the RAIM calculation built into many GPS units (Garmin 430/530, G1000 etc)???
I'll think you'll find that RAIM prediction is very much possible due to the "fixed" nature of the constellation, and being able to calculate if there will the appropriate number of satellites available to facilitate the use RAIM at a given place at a given time.
Obviously, the RAIM in the onboard system will then make sure everything is working nicely, "in realtime", when you actually get there... And provide the appropriate "RAIM unavailable" type warnings should anything be amiss (like a satellite getting hit by debris in the interim etc)