Now that we have an early version of VNAV implementation in the A32NX Experimental build, are RNAV approaches working - in other words using the APP mode for vertical guidance, not having to use FPA mode? I tried this yesterday and it did not seem to work, not sure if it was pilot error though.

No it is not yet implemented.

You can still fake an RNP approach, though. Take the Toncontin RWY 02 RNP approach as an example. As long as the MCDU has the correct altitude restraints dialed in with the correct speeds, the plane will still fly it close to the same way as in APP mode. I did this the other day and was pleased with the results with everything in managed mode.

I'll let you know in a 1/2 hour or so. I'm just about to fly the FLATI3 arrival into KDEN in today's experimental version release... 😁

It can calculate ToD and descend along a star etc, but they're still working on fully taking winds and speed changes into account to make things like ToD point more accurate.  However, yeah unfortunately it doesn't support the actual "glide path" portion of an RNAV approach.  I've faked it by just setting minimums and telling it to descend and it seemed to follow it down on a rough glide path like descent, but when I asked on their Discord they said you should use FPA mode for now for the actual approach.  The one time I tried to make it work as mentioned above it got me down to the runway but it wasn't quite lined up correctly since there's no proper modes yet that would be used for an RNAV approach.  The experimental branch with VNAV is definitely very experimental right now but it's great to see it moving along.

Edited April 11, 20224 yr by flyinion

I got a business related call about 5 mi before TOD as calculated using the flypad descent calculator. I missed starting the descent by about 2 minutes, so it missed the first 4 alt constraints by about 1200' even though I was riding with full speed brakes. There was a flat spot in the descent, and the aircraft caught up with things at that point. From there on, it nailed all of the altitude AND speed constraints. 

Closest flight I've had to a "real" full VNAV & LNAV flight in MSFS. But as flyinion said, still needs a little work on taking the winds into account.

6 hours ago, MDFlier said:

From there on, it nailed all of the altitude AND speed constraints. 

I’m not sure if it was just co-incidence but on my last flight, TOD was far more accurate. Have been finding with the initial VNAV releases that TOD was coming in too late, leaving me high. Last flight nailed it for me too though, so I presume this is improving in the daily updates.

Although… I don’t mind being too high along the decent at the moment as it gives me a chance / reason to use the new HOLD feature to knock off a couple 1000 feet, which works very well.

3 hours ago, RaptyrOne said:

I’m not sure if it was just co-incidence but on my last flight, TOD was far more accurate. Have been finding with the initial VNAV releases that TOD was coming in too late, leaving me high. Last flight nailed it for me too though, so I presume this is improving in the daily updates.

Although… I don’t mind being too high along the decent at the moment as it gives me a chance / reason to use the new HOLD feature to knock off a couple 1000 feet, which works very well.

LOL Same here! First of all I also have the idea the TOD is more correct after the last few updates! And secondly, yes, I also am quite happy whenever I get a chance to use the hold option: it's great and works like a treat!

On 4/11/2022 at 9:34 PM, RaptyrOne said:

Have been finding with the initial VNAV releases that TOD was coming in too late, leaving me high. Last flight nailed it for me too though, so I presume this is improving in the daily updates.

Yeah I saw something either in their Discord or the pull requests that they started adding in some of the rough wind or speed calculations after that initial release of VNAV.  That's why it's getting better at ToD point.  Or maybe it was restrictions or something.  I just remember reading they were adding in more variables to the calculation to start polishing it up.

I did an update today and I think that the latest release isn't working as well as the previous one. It kept getting "Stuck" at each alt constraint. It leveled off to hit a FL210 restriction and then refused to descend to the next one at FL190. I had to dial v/s to -3500 to get it caught up. Then it got stuck on the next one again. 

I will never be critical of anything FBW does, because what they do is hard work and it's freeware (although I donate). But, I'm waiting for a little while to let them work out the kinks in their recently released VNAV feature. I can't really get it to fly a correct descent profile in managed mode. But as I said before, I'm really not upset about it. I can't imagine the programming that goes into writing this software and I know they'll eventually get it. 

Yeah, it’s a work in progress. There might always be a small step backwards with an isolated Experimental update along the way as they move forward and perfect VNAV. This is not just complex coding, it is very advanced mathematics being applied in a simulated environment that does not necessarily respect the laws of mathematics.

Although, the VNAV departure/climb restrictions appear to be working rather well, both speed and altitude restrictions. So you just need to monitor the decent closely, which is required in real life anyway. 

Just use the FPA (Flight path angle - usually 3 °) mode - and you glide down easily 🙂

 

Has there been any news on this front lately? … Support for RNAV approaches?

Go to Fenix and be happy! 😁

After the launch of the Fenix A320 it was impossible to fly another airliner.