Originally Posted by
SilverBullet
The question was definitely RAIM and not RNP. RAIM is old technology as WAAS is now preferred.
If you are using GPS RNAV, RAIM is still very much used. The two are interconnected. RAIM ensures the receiver is getting enough satellites for GPS navigation and WAAS/LAAS provide a correction to a signal to allow for more accurate approaches. No RAIM, WAAS is worthless.