Constraint (ALT / Speed) are not consistent between Nav display and Chart (Using FlyByWire 320)

I’m using MSFS2020 (SU6) and the latest Navigraph (Navdata and charts, ). I’m flying the FlyByWire 320 (dev version, latest build) and I noticed a lot of inconsistencies regarding the constraint (i.e speed and min/max altitudes) between the navigraph chart and constraints displayed in the Navigation Display (on the A320, they are in magenta). It’s not specific to a given SID / STAR but I saw that for many airports (mostly flying from the west coast of USA; SFO, SJC, PDX, SEA, LAS). I would expect these constraints to match, especially during the SID and STAR; that is critical.

I’m loading the flight plan from SimBrief. I then choose the SID and STAR in the MCDU of the A320.

Any ideas how I can get these constraints to match?


Hello, we are looking into this:


Just to be clear; this problem happened before SU6. I’ve been using Navigraph for 4 months and I always experienced some required alt / speed discrepancies between the navigraph chart and what shows up on the A320 navigation display. Let me know if you need more info and/or snapshots.

in general all alt/speed restrictions are included in the data but it could happened that the A320 doesn’t show this correctly due several reasons. In most case its the in-game flightmanagemt what makes it very difficult to handle this.

I will look if I find a representive example because you wrote, that this is not airport/procedure specific.

In the meanwhile, I would try the WT CJ4 mod which use not the in-game flightmanagemt, which use their own, if you see such constraints or not. I assume personally (without verifiying now, but I will), that this is a A320 issue rather a navdata issue.

But I will come back after my analyzing …
Thanks for the report

possible I miss something now and I really need any specific example, but I have tried as an example the PITKN4.GLENO departure out of KASE

Here the chart part:

… and here, what I have in the FBW A320 FMC (using the stable version):

… also on the ND, I see these constraints correctly:

So, the constraints (at least the altitude constraints are included - but also the speed constraints)

Do you have a special example airport/terminal procedure, where I can reproduce your issue (possible you can upload a screenshot also).


Thank you Richard for your initial investigation. I do this problem in many flights but like you said, it could be a problem with FBW. I’ll do more homework today (take snapshots, switch between stable and dev version of FBW) and will report later.

1 - I just created a SimBrief flight from KSJC (origin does not really matter) to KPDX.
2- From FBW A320 (latest dev release), I spawned on KSJC runway.
3- Go to MCDU → init: load the flight plan
4- MCDU → F-PLN, select KPDX, choose arrival
5- Select ILS10R runway, then selectTMBRS2 STAR (GALLO transiton)
6- Check the F-PLAN (by scrolling up and down arrow on MCDU).
7- Noticed that the speed restrictions are there but they show up on the flight plan one waypoint too early.

PORTL has the 270kn restriction on the chart but it shows up at MOXEE
Same things for TMBRS and VANTZ, MYCRO and SSAIL

See snapshots. It’s possible that the bug is on FBW’s side. Can you check on another airplane to see if the restrictions are right there? If so, I’ll work with the FBW team.

Here is an example of a missing ALT restriction.

KSFO, ILS 28R approach. The chart shows a mandatory 7000FT @ ARCHI but the FBW flight plan does not.

Hi again,
thanks for the examples - it looks really that this is an FBW issue. I can reproduce it also with my stable version here. But I have tried your examples in the WT CJ4 mod and here, you see all the correct constraints:

Here the KSFO example ILS28R via ARCHI:


… and here the KPDX TMBRS2 with the GALLO transition:



… and so on.

So, the data are included an correct so far as I see. It looks really that this is an FBW issue, but I know that the FBW guys are working hard to fix all reported bugs :wink:

Cheers and thanks for your details,

THANK YOU VERY Much Richard; I’ll work with FBW to get these problems fixed.

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