I’ve been struggling to work out FBW’s new VNAV (Ver.1) functionality to make consistent RNP (RNAV) approaches at many of my local AU regional airports (e.g. YBSU - RNP Z - RWY31) which all seem to have RNP approaches (and very few ILS approaches except for INTL airports). Each regional airport I chose includes BOTH LNAV and VNAV on the chart.
I’ve spent hours watching countless videos on the topic, and they all use different versions of the FBW A320nx (which makes comparing their A320nx methods to using the latest FBW DEV version of the A320 quite confusing).
Am I correct in thinking the latest VNAV implementation offers a visual guidance on constraints etc, but DOES NOT automatically fly the descent profile for you?
Are you meant to activate LOC or APPR (at times I cannot even turn them on, so I could be missing something in the MCDU programming)?
I use Simbrief to plan flights from YBBN to QLD regional airports, and will try to pick a STAR / SID if one is available in the planning stages. But more often than not I get lost at the approach phase (around IAF) and the plane never descends and I just fly over the airport at 2000ft?!
I use built-in MS ATC but I’m either missing a crucial step (I often get ENTER DEST DATA) or the latest DEV FBW A320nx simply does NOT do VNAV for you - only visual guidance.
Do you have to manually activate the approach on the MCDU or is this meant to happen automatically at the IAF or FAF?
Thanks in advance for any tips. In the interim I will keep studying A320nx RNAV approach videos (and OML there’s so many of them…!).
RNAV approaches are not yet supported in any version I believe.
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So it appears I should I stick to mastering ILS (where available) while also attempting Track / FPA approaches manually for RNAV approaches at all the other airports that don’t have ILS.
@BigCow74 is correct. RNP approaches are not yet supported. We are working on it.
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@Watsi01 Awesome. Cheers for confirming that. I managed to get a few flights working on RNP approaches today. This time I used the constraints button and also completed the DEST DATA fully as well as activating the approach via the PERF on the MCDU soon after take off.
I noticed all the purple flight alt and speed indicators appear on the PFD at the way points and left the ALT in managed mode wherever possible (had to re-engage it a few times and sometimes it simply refused to engage at all..
i.e. the little orange dot would not appear beside ALT selection no matter what I did with the knob).
I noticed that when I did NOT activate the approach via the PERF on the MCDU the A320 was 1000 ft to high at the RNP airport. But when I activated the approach in the MCDU shortly after take off…I was able to engage 100ft in the managed ALT and the plane flew to the correct constraints all the way to the runway 
I was able to perform this RNP approach twice at the same AU airport - YBSU RWY 31 Y RNP.
Did I just get lucky? Or is it just a fluke and I shouldn’t expect the same results for other RNP approaches?
I also turned MS ATC off to focus purely on the FMS approach.
I’ll keep testing tomorrow to verify results.
Keep up the great work. Your team should be immensely proud of their achievements thus far 
You can kind’a work around the lack of RNP approaches with managed ALT mode. When on final appr ALT, dail in the minimum alt (according to charts) and activate managed alt. VNAV should follow the glide slope quite good.
You can activate approach in the MCDU some miles before destination. No need to activate it right after takeoff.
Also important: when in cruise, you’re not in managed ALT. This is normal. You can activate it again, when starting your descent.
A second way to work around the RNP glide path is to go to TRK mode in the FCU and use the according descent angle. On most of the approaches it is around 3° down (see approach charts).
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@Watsi01 Love your work, thanks for the great tips my friend. I now have a better understanding of how it’s meant to work. I didn’t realise the alt managed mode turns off in cruise.
So when RNP approaches are fully implemented, will that mean the pilot can simply press APPR to activate the RNP approach before the IAF (i.e. no need to activate via fhe MCDU)?
Research suggests that the stock MS A320 Neo also does not yet supporr RNP. Only the £50 Fenix A320 supports it.
I’ll get more practice in using the FPA while we await future RNP updates from the FBW team.
Cheers.
Oddly enough, I think you can do RNAV approaches on the stock A320, but that’s not enough of a reason to use it for anyone on PC 
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Well I’ll be darned?! Gives me a few more things to test in the morning. After spending a week on the FBW A320nx…I’ll prepare to be disappointed… “where’s the bloody EFB?!” 
You always activate approach mode in the MCDU. Also with ILS approaches. Actually approach mode activates itself automatically at a certain point. Mainly it’s a speed thing. The plane ‘has to know’ at a certain point that you’re doing an approach now, to adjust it’s speeds accordingly (provided that you’re still in managed speed mode on the FCU).
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Does anyone knows how to enable GPWS sound outside of A32NX cockpit??! I need it for some videos of landings…
APPR mode auto activates at the D circle on the ND, this will reduce the aircraft speed to green dot in a clean config, then gradually reduce the speed as the flaps are deployed.
When is FBW going to have RNAV approach resolved?? and Weather Radar??? The A320 v2 Inibuilds has that and more!
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My speculation is RNAV RNP will appear alongside the release of the A380X, which seems it might be soon™.
They recently released their updated flight management package where they indicated it was part of the tools necessary to implement RNAV approaches.
The APPR “Phase” is activated via PERF page on MCDU or automatically at the D Circle just before IAF usually. Hopefully you are not confusing the APPR “Mode” pB on the FCU which arms the Glide Path/slope on RNP approaches (still not working in FBW) and G/S and LOC on ILS. THe Inibuilds 320 neo V2 has RNP APPR pB capabilities, which displays glidepath/GS FINAL APP on FMA if you want to practice. You probably meant APPR Phase anyways. I commented so people don’t confuse the 2. No offense. RNP AR/ RF approaches are very important and I expect the volunteers at FBW know this.
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