View Full Version : Still LNAV problems

10-03-2010, 06:19 AM
Hi all,

As you know, due to severe problems with the latest builds I revert to buld 402 or 406.
I have since a long time, apparently a bit dependent on where I fly, a problem with VNAV. If I take in the MCP the heading to a waypoint, say 150 degrees, all instruments (PFD, HD) and also FS in the overhead text bar are showing 150 (also track is 150 without sidewind) but the CDU is showing something like 154 to the next waypoint. This means that with VNAV I always fly besides the flightpath and when a waypoint is reached my a/c is turning sharply to this waypoint, evolving then again to a wrong direction for the next one.
This problem has been raised several times in these forums with the following (possible) solutions:
1) check for double afcad files.
I have checked and don't find any double afcads. Moreover my FS is giving the same heading as on the PFD which isn't the case when double afcads are present.
2) don't import external flight plans but program them in the CDU
Importing flightplans or making them in the CDU doesn't give any solution. the problem is there identical in both cases
3) use another aircraft.txt
Someone seemed to resolve the problem by reverting to Bob Scott's old aircraft.txt file. It didn't help with me and moreover I cannot imagine that this would help.

So, I hope that someone, who had also this issue, could solve it and want to share his solution with me, because I am really desperate.

joaquim Sa Nogueira
10-24-2010, 11:56 AM
Hi Robert,

I did have once the same problem and the fault, in my case, (I'm using FS9 with the complete PM suite and PMDG737700 model, in a cockpit) was double scenery files, since I had installed the RW12 and EZScenery complete libraries (available for free) download in the net and one of them (I don't know which file or files in particular)enter in conflict with the OZ Australis EZ scenery set (I don't know either, which file or files in particular) which I had installed also. Since the moment I put those 2 files (RW12 + EZScenery) as non-active, my problems are gone!!!

Don't know if this can be of any help to you, but ... we never knows


10-24-2010, 01:05 PM
Thanks, Joaquim,

All info is welcome and I hope more people should discuss here this issue because it is really annoying.

I have the same configuration as you have (FS9 + all PM + PMDG7377000 - without gauges)
I think that double scenery or double afcad files are indeed the little devils. I found some "double" (different, but for same airport) afcad files and after deleting them the problem was solved. But, suddenly I was flying in the Mediterranean (neighborhood of Cyprus) and it started again. Afterwards, I discovered that I had double afcads in some Greek scenery. I have afcad files for the airports of the Greek Airports Project (GAP) and I found other ones for the same airports in one of the folders of the Hellas Scenery Project (HST). Now, I have deleted the latter and everything seems to work again. Touch wood. I wonder if this problem is triggered whenever you start to need the (double) scenery elements in FS.

The strange thing is that by using the navigation function of FSCommander the path was nicely followed, whereas the PM-CDU with LNAV did it wrong as described in my first mail.

Best regards

joaquim Sa Nogueira
10-25-2010, 07:08 AM
Thank you Robert,

The thing I can not undertstand is that in principle my "double" scenery issue envolving OZ Australis EZ scenery and Rw12/EZscenery libraries, should occur when flying over or near Australia, in order to have FS9 reading the scenery files of that zone, since, in priciple, the RW12/EZscenery libraries are read "all the time" (I think).

But the fact is that I was flying over the USA (KABQ>KDEN) well far away from Australia!

When re-doing the same flight, after editing the FS9 Scenery.cfg, and puting the RW12 and EZ libraries on non-active mode, I verified that the problem was solved (coincident FS9/PM CDU paths, correct LNAV, ND VOR Hdg indicadors pointing correctly to any Vor station - all the things that, before, were showing problems because uncorrectly handled.

With such modified FS9 scenery.cfg file, flying in other places inclusive Australia shows no problems whatsoever!

So, the idea that you need to be flying over a certain area to activate the bgl files of such an area seems to be wrong...

Your thoughts on this?


11-01-2010, 12:38 PM
Yes, Joaquim, that's strange.

Anyway, for the moment it runs fine, with the exception that I still have the features as shown on the picture in my previous post (i.e. overshooting the route direction in the case of significant angles in the route.

Best regards