I am having a problem getting the Autopilot in the NGX to track either the LNAV magenta course or even the selected heading when choosing heading mode. This has been a problem since SP1b.

Looks like you might be outside the intercept range for the LNAV, need to be inside of 3nm as I recall and on an intercept heading.

No, I don't think that is not the problem. I selected LNAV when I was on an intercept heading to the fix. Here's what it looks like when I select heading and try to get it turned back towards the next fix. It maintains a track of 072 even though I have selected a heading of 103.

No, I don't think that is not the problem. I selected LNAV when I was on an intercept heading to the fix. Here's what it looks like when I select heading and try to get it turned back towards the next fix. It maintains a track of 072 even though I have selected a heading of 103.

It looks like you are in a right bank turning towards that heading. It may be you need to adjust your max bank angle ( I dont use that MCP), but regardless, you need to be on an intercept heading and within about 3 miles of the track line before LNAV will engage.

LNAV IS engaged in the first pic !My guess is it is weather/wind related.Fred.

Yes it shows active, but obviously not tracking

If you are not on an intercept path, the CDU will have a scratchpad message saying "not on intercept hdg" or close to. Have you tried to use HDG to get on the line and then go into LNAV? Any open discos in your LEGS page?

My guess is it is weather/wind related.

That'd be my guess too - what are you using for weather?

There seems to be a big discrepancy between the track line and the wind speed/direction indicator. Are you getting violent wind shifts in speed and/direction? I get this when using RW weather in FSX

I experience the problem with FSX weather or Active Sky Evolution. It does not seem to be wind shift related. I have disabled turbulance effects. I have tried it with the Clear Skys weather theme with no winds. The plane turns erratically whether in heading or LNAV mode. Here is a shot showing a hard left turn while under heading mode.Very frustrating. I am at a complete loss.

I had a similar issue, but is now fixed after some advice.http://forum.avsim.net/topic/360918-i-have-never-noticed-this-before/page__p__2239042#entry2239042

Thanks for the suggestion. I checked my wind turbulance settings per the HiFi manual and they are as recommended. I do not think this is a winds problem.

I noticed you have the Honeywell MCP in the first shots, but must have switched to the Collins at some point for the last shot. Was that done during a flight? Or did you start fresh and change the MCP? Maybe that is an issue? Thats all I got.

I noticed you have the Honeywell MCP in the first shots, but must have switched to the Collins at some point for the last shot. Was that done during a flight? Or did you start fresh and change the MCP? Maybe that is an issue? Thats all I got.

That's a visual change only - the only thing that gets turned off code-wise when you switch between MCPs is the fail operational autoland code. All of our options are designed to be swapable in flight, there's no problem with doing that.I would like to know if anyone can replicate this thread's issue without any weather whatsoever loaded - use the clear skies theme, make sure AS or REX etc are off and not running, and use FSUIPC's "Clear all weather" button. If you can replicate this under those conditions, let me know.

I have submitted a ticket. The last shot was a special flight setup without weather (Clear Skys) to try to eliminate winds as a factor. One more data point. I having the same problem with my PMDG 747-8. I think whatever is the cause is common to both. I un-installed both the 747 and NGX, then re-installed to see if it would help.