After having installed FSX Gold, mainly to be able to fly this great add-on, I used the usual recomended tweaks, and everything is perfect and smooth.

 

The FPS are locked ( in FSX ) at 30, the V-Sync set through Nvidia Inspector, but today I decided to disable V-Sync, and set the FPS to Unlimited.

 

Went flying, first the A2A C172, then the PMDG 777, using RWW injected,, which is rainy and windy at all levels around the Iberian Peninsula.

 

With from 24 to 100+ FPS I was really happy and had, apparently, no problems. Then, during one of the legs, wind winds at FL370 around 90 knot from 3 o'clock, I experienced, for the very first time in my PMDG user life, S-turns...

 

The ND started showing them, and then I switched to an external view. The aircraft kept S-turning along the route, always overshooting and FPS were sometimes very high ( 100 or more! ).

 

Well, since the only thing I had modified was V-Sync and FPS limiting, I closed FSX, went back and set FPS limited at 30 and V-Sync, and repeated the very same flight, just a few minutes later, facing the exact same winds at cruise after taking of from LEMD. This turn around I experienced nothing but perfect following of the route.

 

Might it have been caused by having set unlimited FPS?

 

Doubt anything to do with frame rate.

 

Simply tick the "supress turbulence" box in registered FSUIPC. Done.

 

I have the adjacent boxes ticked too.

That solved it for me.  I only ticked "suppress turbulence" and the problem was fixed immediately.

 

thanks,

 

jeff

I used to suffer from such problem flying all of the PMDG aircrafts. Seems caused by unique aloft wind data with turbulence, especially flying in some of the default weather themes, like Heavy Snow, Major Thunderstorm. Maybe just lowering some of the bars in realism settings is OK..It occurs to me that once upon a time (far before 777's release) PMDG seems to have announced about this problem. But I have forgotten which to lower. I just lower all the settings and let FsPassenger handle the realism required. And everything just goes well.  I did not turn off the turbulence effect within FSX, nor suppress the turbulence via FSUIPC, because I think that "No Turbulence, No Challenge"...

I did not turn off the turbulence effect within FSX, nor suppress the turbulence via FSUIPC, because I think that "No Turbulence, No Challenge"...

 

 

It doesn't supress it completely. Still a challenge.

Well, the only thing that puzzles me is, appart from never having had this problem before ( and hence the coincidence of it happening exactly when I set my FPS to unlimited, although I agree that apparently this is not related... ), is that I flew the very same route, with the very same weather injector and winds, 10' later, and had no S-turns. Actually, as the flight progressed "we" hit zones of 100+ knot wind, with variability and turbulence, and the 777 had no problem following it's tracks (?)

 

I will try to set the same graphics, no V-sync, and FPS=unlimited again and try to reproduce the same situation.

 

Thanks for you answers!

This only happened to me twice with the ngx. The last time was from mco to bos. Two thirds into the route, it started to s turn after some turb. After that was corrected, I fell asleep at the controls and wake up in the middle of nowhere in Quebec with no fuel and 5,000 feet altitude. I looked at the fsx map and I was obviously way off route but the interesting thing was that the plane did s turns this whole time it was off route. :mellow:

" hit zones of 100+ knot wind, with variability and turbulence, 

 

 

Wind changes, variability, gusts, windshear, mountain wave, jetstreams and so on

1. are not what FSX calls "Turbulence" (yes they 'feel turbulent')
2. are not effected by turning "turbulence effects off" in FSUCIP/Weather generators like ActiveSky etc.
3. Will not cause S turns (Although some severe ones can cause overspeeds or stalls)

 

 

Wind changes, variability, gusts, windshear, mountain wave, jetstreams and so on
are not what FSX calls "Turbulence" (yes they 'feel turbulent')
are not effected by turning "turbulence effects off" in FSUCIP/Weather generators like ActiveSky etc.
Will not cause S turns (Although some severe ones can cause overspeeds or stalls)

 

And that's why I also think it had to do with setting the FPS to unlimited, and turning off V-Sync, even if it sound illogic...