Very annoying LNAV bug, please help me PMDG

[ArjenVdv 190]

Hello,I already submitted a ticket on this problem about 48 hours ago, but I didn't receive any response yet.This is my problem, it's already been discussed a little, but I can't seem to be able to solve it.When I'm at cruising altitude, I'm mostly flying from SID to STAR. In this case, I was doing a flight from HELX (Luxor) to EHRD (Rotterdam). I have FSX's default real world weather engine switched on. FSUIPC's weather smoothing has also been turned on and working. Whem I'm at cruising altitude (FL370 in this case), the weather obviously gets updated every 15 minutes. When there is a change in wind direction or speed, no matter if FSUIPC weather smoothing is on or off, the aircraft can start to do two things:1. Most of the time it's doing S-turns. It's doing 5 degree turns (each of about 5 seconds), from the left to the right), it keeps repeating this over and over, and it just doesn't get back on the magenta line (LNAV path). After a while, the lateral deviation can be as big as 20 nm, and sometimes even 50 nm! I don't understand it, why doesn't the aircraft just stay on the magenta line, even after a weather change?2. After a weather update/change, it's doing nothing at all. It keeps flying in the same attitude, VNAV is still working perfectly and maintaining altitude, but LNAV however, is doing nothing to get back on the magenta line. It just keeps flying, while the deviation to the magenta line is getting bigger and bigger. When I use HDG SEL to get the aircraft back onto the magenta line, and then turn on LNAV again when I'm back on track, the AP steers to the old heading again after the last weather change, heading away from the magenta line again!This is in my opinion very annoying. Am I missing something? I don't think so...Apart from this, I love the NGX, it's an amazing productPlease also note the two pictures, where you can clearly see that the right modes are on, and that the aircraft is heading away from the magenta line, doing S-turns.P.S. I didn't have this problem YET with the 900WL (please not the "yet"). I only had this problem so far with the 800WL from Transavia and KLM. Add-ons: Aerosoft airport sceneries, Airbus X, PMDG planes, REX 2.0.Bojote's aircraft.cfg, created for my systemuiautomationcore.dllPC specs (not that good, but overall performance is OK with the tweaks):i7 860 2.8 GHznVidia GTX320 1GB6GB DDR3 RAM1TB HDDCould someone (PMDG) please help me? That would be highly appreciated.Thanks a lot in advance,Arjen VanderveldeCan't upload the pictures, I made them using a video camera and the files are too big. How can I make screenshot directly from the ND and PFD?

[emvaos 13]

Hello, I already submitted a ticket on this problem about 48 hours ago, but I didn't receive any response yet.

It is very annoying that you don't read the forum or search for particular issues covered here and in a million other places...Turn off that stupid turbulence effects in Options/Display/Weather. Tick DIsable Turbulence and thermal effects.in that submenu. What FSX does, is create a "void" around your plane to simulate such effects thus eliminating flight control input and making the plane temporarily uncontrollable. TURN IT OFF !

[ArjenVdv 190]

It is very annoying that you don't read the forum or search for particular issues covered here and in a million other places...Turn off that stupid turbulence effects in Options/Display/Weather. Tick DIsable Turbulence and thermal effects.in that submenu. What FSX does, is create a "void" around your plane to simulate such effects thus eliminating flight control input and making the plane temporarily uncontrollable. TURN IT OFF !

Thank you Dr. Vaos for helping me. I'm sorry if I missed that part about turbulence. But I don't understand it... I'll have to turn turbulence off and thermal effects to solve that problem, but that means I'll never be able to fly the NGX with turbulence on? I would like some challenging landings and approaches. And why don't any other of your aircraft have these problems? Will the NGX be made compatible with FSX's turbulence in the next SP?Thanks in advance,Arjen Vandervelde

[nrcrate 40]

Thank you Dr. Vaos for helping me. I'm sorry if I missed that part about turbulence. But I don't understand it... I'll have to turn turbulence off and thermal effects to solve that problem, but that means I'll never be able to fly the NGX with turbulence on? I would like some challenging landings and approaches. And why don't any other of your aircraft have these problems?Will the NGX be made compatible with FSX's turbulence in the next SP? Thanks in advance, Arjen Vandervelde

You must have missed his first sentence....

[michal 44]

Will the NGX be made compatible with FSX's turbulence in the next SP?

Why make a good product compatible with FSX's turbulence which is a totally flawed implementation?. I guess you could be asking when FSX's weather gets fixed - this would be far more appropriate question.

[emvaos 13]

Thank you Dr. Vaos for helping me. I'm sorry if I missed that part about turbulence. But I don't understand it... I'll have to turn turbulence off and thermal effects to solve that problem, but that means I'll never be able to fly the NGX with turbulence on? I would like some challenging landings and approaches. And why don't any other of your aircraft have these problems?Will the NGX be made compatible with FSX's turbulence in the next SP? Thanks in advance, Arjen Vandervelde

Happy to be of assistance. No, I am afraid no advanced plane will ever be compatible with the "void" mechanics that FSX is using for "turbulence". UNless we trigger slew from inside. It is like the airplane flying in "space" where aerodynamics and control inputs have no effect. WHat can one do ? It is OK for small GA stuff but for an airliner with lots of mass and inertia it simply cannot happen. Please remove that gimmick it has nothing to do with real life.

[ArjenVdv 190]

Why make a good product compatible with FSX's turbulence which is a totally flawed implementation?. I guess you could be asking when FSX's weather gets fixed - this would be far more appropriate question.

Ok, I want to search in the forum and i already did that before, but I can't find anything. Probably because I'm using the wrong keywords.So now turbulence is off, does that mean I won't have such updrafts and downdrafts in very bad weather during approach? You know what I mean, that weather which makes it very challenging to land?Arjen Vandervelde

[Dougal 165]

You don't need to use the turbulence option to get 'challenging' weather - just try some xwinds with gusts on approach!

[Sawydz 4]

Arjen, Are you using ASE for weather? If you're using it in DWC or Smooth Cloud Transitions modes there is some conflict between FSUIPC's weather engine and ASE. It's easy to solve that problem, first turn that turbulence effects off, then modify those settings in (registered) FSUIPC's .ini file: SuppressCloudTurbulence=YesUpperWindGusts=NoSuppressWindTurbulence=YesSuppressWindVariance=YesWindTurbulence=NoSuppressAllGusts=Yes Regards,

[ArjenVdv 190]

Happy to be of assistance. No, I am afraid no advanced plane will ever be compatible with the "void" mechanics that FSX is using for "turbulence". UNless we trigger slew from inside. It is like the airplane flying in "space" where aerodynamics and control inputs have no effect. WHat can one do ? It is OK for small GA stuff but for an airliner with lots of mass and inertia it simply cannot happen. Please remove that gimmick it has nothing to do with real life.

Mr. Vaos,Thanks for your help. But the problem is not solved I'm afraid. I ticked "Disable turbulence and thermal effects on aircraft", then I used HDG SEL to get the airplane back onto the magenta line. When I was nearly back on track, I engaged LNAV again, and right now, the autopilot turned right again, heading away from the magenta line again! At about 30 degrees off the leg heading. What can I do now? I'm pretty frustrated right now... I'm sorry.Thanks in advance,Arjen Vandervelde

[DavideLeeSim 0]

sorry to go off topic. on the manual i dont see if i have to disable "detect crashes and damage". what i should do? about LNAV i had same problem too and i disable it and now everything work ok

[FlavioSSA 44]

Interesting. Never knew about this "default turbulence" issue before.

[marijn747berg 1]

Maybe a stupid question, but did you restart FSX? And the old, simple and very underestimated trick of switching the computer back on?Cheers

[ArjenVdv 190]

I turned off turbulence now, and everyting got really boring. When doing an approach and landing, the turbulence, updrafts and downdrafts were making the approaches challenging and exciting. Now that's all gone... Why don't I have to turn it off in the 747 and MD-11? Never had any problems with those aircraft. So why does the NGX have problems with it at cruising altitude? Seems so strange. Is it worth buying ASE? Can I use turbulence there without having problems?Arjen Vandervelde

[emvaos 13]

Yes ASE is a must for serious simming (my opinion as a simmer). As long as that "spacial anomaly" thing is turned off you are ok. The exact same happens in all serious planes I know that use custom autopilots, i.e. the LDS 767 the MD11 and the B744. There threads no end on this subject.