As far as I understand, there are mainly 3 types of RNP approaches:
- LNAV/VNAV - we have a set of fixes with altitudes and flying it
- LPV WAAS/EGNOS - same as 1, but aircraft use special receiver equipment based on geostationary satellites, that's why it's so-called SBAS (sattelite-based)
- LPV GLS - which is same as ILS, uses GPS + signals from ground equipment. It's so-called GBAS (ground-based)
Let's take EPRZ RNP Rwy 09.
Here we can see three options:
- LPV CAT 1 - which I assume shall use EGNOS (V in LPV is vertical)
- LNAV/VNAV - which I assume use only FIXes and altitudes
- LNAV CDFA - which I assume uses LNAV and I need to descend somehow (V/S or glide path angle)
In terms of 737 NG, LNAV/VNAV and CDFA are straightforward.
- Do I need to "tune" WAAS/EGNOS channel somehow? Referring to this LPV/LP approach (RNAV with WAAS): What is actually the "channel number"? it seems like no
- If I don't need to tune EGNOS channel, what is the difference between LNAV/VNAV and LPV WAAS/EGNOS regarding the procedures? How do I know, if aircraft is ready for LPV with EGNOS/WAAS?
- Approach is called LPV CAT 1, on the other hand, in EPGD RNP approach named just LPV. What is the CAT 1 here?
- Can IAN be used (if equipped) instead of LPV, LNAV/VNAV and LNAV CDFA?
- I assume something here is related to ANP/RNP, but chart has no RNP minimum values listed here. What are the general rules, I probably missed?
FCOM 737 says only about ILS/GLS (normal procedure) and supplementary SP 4.7 Instrument Approach - RNAV (RNP) AR, but in such case it's non-AR approach.
I'm not 737 pilot yet, using 737 in simulators only
