I was recently advised on VATSIM to do an RNP approach into YMML (Melbourne) RWY34. As there are no RNP charts for YMML, (as distinct from some other airports that do have RNP procedures - such as SBRJ) do I just execute an RNAV approach? i.e. what differs in terms of what I need to plan on the FMC and what I need to monitor/perform…?
I assume you have completed the flight by now. What did you do? I think many RNP approaches are marked as rnav only with the required navigation accuracy mentioned somewhere in the chart. So basically, you will need to find that required accuracy value and monitor you navigation accuracy in fms during the approach and if it goes above the required number, probably you need to do a missed approach. And AS I understand, MSFS does not model decreased navigation accuracy, so in msfs, RNP and RNAV are essentially same. Note that I am not a real-world pilot but told you all this from my simming experince int the last couple of years. So, i may be very wrong here with some small details.
OK…thanks for that…Yes, completed the flight really by RNav…I’ll see if a pilot comes on board…
You activate FLS landing system in the Fenix EFB.
The Airbus will do the rest like a pro 
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Except that OP is asking for a procedure and never mentioned that it’s being flown in Fenix. I believe pmdg 737 also models the IAN feature (similar to FLS in Airbus) but that doesn’t really answer the general question. In this airport, FLS may work, but there are RNP-AR approaches where FLS should not be used. And FLS is an airframe specific option anyway, so if you are going for a bit authentic experience, you can’t just install an FLS system in an Airbus mid-flight in real life .
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ah…ok thanks for that
Yes I see - via ASA but not on Chartfox…thanks
Moved to #self-service:atc-traffic-navaids
RNP does exist for YMML RWY34, but any aircraft in the sim will fly it as an RNAV if equipped with such an FMS.
great thanks
Naming conventions for RNP, RNAV, GNSS, etc approaches are a dog’s breakfast.
There is currently a process to rename all RNAV approaches to be RNP approaches. The old RNP approaches will be “RNP (AR)” (approval required).
While this is happening there will be a mix of RNAV, RNP, and RNP (AR). The best way to ensure you’re flying the correct approach is by the identifying letter, eg RNP Z or RNP M.
So in the case of Melbourne, if you’re cleared for the RNP Z and your charts only have the RNAV Z then that is the correct approach to fly.
Clear as mud.
Edit: Reading ICAO again, I see it’s even more confusing. RNAV (GNSS) becomes RNP and RNAV (RNP) becomes RNP (AR). Easy to confuse a newly named RNP approach with an older RNAV (RNP) approach but the latter requires specific operator approval.
There’s some more info here: https://www.icao.int/MID/Documents/2018/AIM%20SG4%20-%20MIDAD%20TF5/MIDAD%20TF5%20AIM%20SG4%20-%20PPT6%20RNAV%20to%20RNP%20Charting%20depiction.pdf
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greatly appreciated the explanation…thanks
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