Whether one can file S1 or S2 is somewhat academic, at least in the US. It does not affect routing or approach assignment and ATC has no easy way of determining what you filed. If you request an RNAV (aka RNP APCH) approach, it will be assigned to you, regardless if you filed S1 or S2 or none of the above.. Maybe at some point someone will care. AC 90-105A has this statement in the Appendix A:
A.6.4 LNAV/VNAV Line of Minima Qualification.
A.6.4.1 Stand-Alone Systems. Stand-alone TSO-C146 Class 2 or 3 systems meet the aircraft qualification requirements for RNP APCH operations using the LNAV/VNAV line of minima provided that the installations meet at least the performance and functional requirements of this AC.
I think the intent of S1 and S2 PBN code is to indicate if an aircraft is capable of flying an RNAV (aka RNP) approach to the LNAV or LNAV/VNAV line of minima and the field 10 equipment code of B indicates a capability of flying to an LPV minima, but one is not cleared to a line of minima, they are cleared for an RNAV approach and fly the procedure to the line of minima the pilot chooses, subject to their equipment and signal limitations.
Do approach controllers in the EC know what you filed for PBN codes S1 or S2 and does it matter.
@NCYankee what you are describing for RNP and RNP approach is much the same here in France. It may be that ATS services have details such as S1 or S2 or B, as IME they probably have full flight plans appearing on their computers, but whether they actually look at such details for every flight or even for any flight I very much doubt. Its down to the PIC to make sure the flight can be safely flown down to the minimums required. If you make a mess of it you might be in for some sarcastic comments. If you make a right mess of it you could end up dead. Its PICs responsibility to meet the RNP.
On ICAO FPL codes for RNP APV, are there that many L/VNAV procedures that can be flown under ISA conditions by BARO and not SBAS?
I recall at some point CAA disabled SBAS L/VNAV in RNP datablocks but they reverted that change after some pressure, now even with loss of EGNOS SoL, one can fly L/VNAV in Cambridge using G430W
In the other hand, DGAC has few RNP approach (and RNAV departures & arrival) that are “GNSS only” in places where DME have been removed
It may be that ATS services have details such as S1 or S2 or B, as IME they probably have full flight plans appearing on their computers,
The situation in Europe is likely to be as posted above i.e. ATC don’t see the aircraft capability.
On ICAO FPL codes for RNP APV, are there L/VNAV procedures that can be flown under ISA conditions by BARO and not SBAS? under ISA conditions by SBAS and not BARO?
Wrong thread?
Ibra wrote:
On ICAO FPL codes for RNP APV, are there that many L/VNAV procedures that can be flown under ISA conditions by BARO and not SBAS?
I know of cases where RNAV approaches with L/VNAV minimums can only be flown with aircraft equipped with Baro VNAV. A good example is at TJSJ San Juan Puerto Rico RNAV(GPS) Rwy 10 has this note: WAAS VNAV not authorized. This is because the WAAS VPL service volume for L/VNAV is not reliable to meet signal requirements at that location.
Ibra wrote:
I recall at some point CAA disabled SBAS L/VNAV in RNP datablocks but they reverted that change after some pressure, now even with loss of EGNOS SoL, one can fly L/VNAV in Cambridge using G430W
The GNS430W is incapable to provide vertical guidance on an RNP approach when outside the SBAS SV. Also the VPL of 50 meters is required to provide the L/VNAV annunciation or to provide +V.
New Zeland and Australia now have RNP with L/VNAV minima using SBAS (and BARO) and yet they are outside SBAS SV volumes
Of course only GTN on higher versions allows it, G430w require one to be in SV SBAS volume for SBAS L/VNAV to work
I understand L/VNAV with GNSS is less reliable outside SBAS SV but I guess it’s up to each NAA to approve it’s usage and publish it’s minima in plates and databases
Ibra wrote:
Of course only GTN on higher versions allows it
This is not correct. One must have a L/VNAV annunciation or LPV annunciation to fly an RNP approach to an LNAV/VNAV minima using SBAS vertical guidance. You can only get the annunciation when in an SBAS service volume and with a VPL of 50 meters. LNAV+V is available outside the SBAS service volume, but this is only advisory and is not to be used for flying a RNP approach to a LNAV/VNAV line of minima.
This is from the Australian PBN site:
non-precision instrument approach procedures (NPA) – RNP APCH are titled ‘RNAV GNSS’ on Australian approach charts1), with LNAV or LNAV/VNAV landing minima.
It’s important to be aware an LNAV+V, LP+V, L/V or LPV (localiser performance with vertical guidance) navigation system provides ‘advisory’ vertical guidance only, and cannot be used for Baro-VNAV operations.
Approach procedure with Vertical Guidance (APV)
For aircraft fitted with navigation systems certified for Baro-VNAV approach operations, PBN has also enabled the addition of actual (as opposed to advisory) vertical guidance derived from barometric sources, permitting the use of LNAV/VNAV landing minima. The roll-out of Baro-VNAV in Australia is in line with International Civil Aviation Organization (ICAO) recommendations to establish safer approaches to landing.
From 2028, Satellite-Based Augmentation System (SBAS) enabled APV will be available with the implementation of the Southern Positioning Augmentation Network (SouthPAN). See Geoscience Australia for more information on the SouthPAN project.
Guys, I think this thread has been comprehensively milked to death 
We have no idea how the French proposal will be finally worded or even whether it will be implemented (some obvious problems).
Can I suggest the discussion is moved to here. Better still start a new thread with a clear subject but almost nobody wants to do that
