Veering off course randomly

[Luke160388 5]

Ive been following this forums since release and I haven' seen any mention so here goes. 

 

Im currently doing EGLL-VTBS with the following route:

DVR 5101N L9 KONAN UL607 AMASI UM149 BOMBI UL984 PADKA L984 FASAD B493 TIKNA A87 KEKAL N644 ABDAN LEMOD N644 DI A466 SAMAR M890 LLK R460 CEA L507 OSUKA DCTARONS

 

Now between OSLAN and BULIG on L984 airway the plane just decided to turn left off the magenta line and make the plane scream "bank angle bank angle". This is the 2nd time its happened, the first on EGKK-TBPB. Now I'm new to the plane and still learning things but I don't know what is causing this to happen. The magenta line is drawn properly and there are no discos.

 

Any ideas?

[fabiopittol 0]

That happened to me today. (that's why I found this topic)

 

While flying from VHHH to KSFO, already at cruise level, I noticed everytime the plane faces turbulence the A/P goes a little crazy, making huge turns.

 

When I was watching the Pilotseye.tv video of the Aerologic's 777, I heard the captain saying that it happens indeed with the aircraft eventualy, but he also said that keeping the autopilot engage, the aircraft corrects its course withing the limited bank angle.

 

As you said, the PMDG 777 is going beyond the 30° bank angle and triggering the alert. Also I found the aircraft really struggling to find its course back.

 

I dunno if it's a bug or we are doing something wrong. Maybe switching the bank angle limiter at the MCP from AUTO to 30 will correct this. I'll try that when it happens again.

 

For now, what I did to correct while it was happening was to switch to HDG HOLD mode, and when the wings were leveled I set a HDG course following the magenta line (LNAV) until leaving the turbulence zone, and then I finally back to LNAV/VNAV modes.

[3-2-1-Now 126]

When I was watching the Pilotseye.tv video of the Aerologic's 777, I heard the captain saying that it happens indeed with the aircraft eventualy, but he also said that keeping the autopilot engage, the aircraft corrects its course withing the limited bank angle.

 

:blink:   I seriously think you are mis-understanding something. The only thing I can think of there is hitting turbulence, because without a serious systems failure, there is no other reason for the aircraft to suddenly divert off course.

 

As for the problem in FSX - check your weather program. You don't even mention if you're using one, but they are known to cause weird issues.

 

Best regards,

Robin.

[fabiopittol 0]

I seriously think you are mis-understanding something. The only thing I can think of there is hitting turbulence, because without a serious systems failure, there is no other reason for the aircraft to suddenly divert off course.

 

I sure may be misunderstanding something. But watching again, the captain actually was talking about wake turbulence. He says exactly the following:

 

"The last time I've had such turbulences years ago during an approach to Bangkok with a A330, we were behind a Thai B747. The autopilot was flying when suddenly the aircraft banked by 30°. There was a lot of tension. The co-pilot wanted to disconnect the autopilot. I told him not to do it and let the autopilot fly. It was the right choice. It then banked 30° to the other side before it stabilized itself. Although it wasn't that strong, everything returned back to normal."

 

That's from where I got that theory. But, who am I to state something about it!

[Luke160388 5]

I use AS2012 and it definitely wasn't turbulence that caused mine to go off course, well not that I noticed. I had to use heading select to put me on a vector to intercept the magenta line agin to correct it.

[3-2-1-Now 126]

That was brave... hitting WAKE turbulence on approach no less, and he just leaves the autopilot to fly it??? :blink: He'll be a statistic some point in the future.

 

That's the kind of attitude that results in delayed reaction to a major problem and not having sufficient time to correct as a result. Plenty of smoking holes to cite for that one...

 

Best regards,

Robin.

[kamaz74 81]

If you are using Active Sky, disable DWC (Direct Weather Control) and enable Smooth Cloud Transitions. Complex addons like the 777 and NGX don't like DWC. Causes the airplane to do very strange things. In addition, I had found with the old PMDG 737 (FS2004) that if you didn't update the macdec.bgl file, that the airplane could veer off course for no apparent reason. I believe it has to do with magnetic variations that change every year. The latest file is for 2013 and it is available here: http://www.aero.sors.fr/hfiles/MagDec_Update.zip

 

This is all I can contribute, hopefully it helps someone.  ^_^

[CaptCraig 226]

No veering here.  I had it when I was doing my first hundred hours in the NGX.  Had to buy FSUIPC, enable wind smoothing, and change AS to DWC mode.  I was happy I could leave turbulence on though as it is quite enjoyable.  

[neas1982 42]

That was brave... hitting WAKE turbulence on approach no less, and he just leaves the autopilot to fly it??? :blink: He'll be a statistic some point in the future.

 

That's the kind of attitude that results in delayed reaction to a major problem and not having sufficient time to correct as a result. Plenty of smoking holes to cite for that one...

 

Best regards,

Robin.

 

Are you a real life pilot? If not ... I would leave it up to the professionals to decide what's right or not.

[hopskip 253]

Are you a real life pilot? If not ... I would leave it up to the professionals to decide what's right or not.

 

The pilots of Asiana Airlines flight AAR214 were professionals too.

 

Not to mention Air France 447.

 

Just because it's a job you've been doing for years and years doesn't mean that everything you think, every habit you have, and all of your training is correct.

 

"Children of the Magenta".

 

for us flightsimmers though,

Ensure FSUICP and/or ActiveSky etc has "suppress Turbulence" enabled. Gusts will still happen, and so will that bouncing effect when passing through turbulent clouds, however the clear air turbulence FSX unrealistically makes will be gone. The FSX turbulence has little resemblance to the real thing.

For instance, a crosswind will usually hit the aircraft, and effect the tail more. In the real plane, the nose will turn "toward" the wind as a result.

In flightsim, the aircraft is moved in it's entirity, sideways, this will cause wind to hit the tail, and the nose will turn "away" from the (direction the wind would have come from) as a result.

 

It's better to turn it off. That way your PMDG autopilot won't bank in the 'wrong' direction.

 

Majestic Software's Q400 ignores all turbulence in it's own flight model.

 

FSX native models use the "FSX Autopilot" which is... pretty simplistic.

[neas1982 42]

The pilots of Asiana Airlines flight AAR214 were professionals too.

 

Not to mention Air France 447.

 

Just because it's a job you've been doing for years and years doesn't mean that everything you think, every habit you have, and all of your training is correct.

 

"Children of the Magenta".

 

 

And off course we as simple flightsimmers interacting with a piece of software are qualified to judge these professionals?

[CaptCraig 226]

Humans JUDGE people everyday.  It's what we do.  We ALWAYS rank ourselves against each other.  If you don't see that then you are mentally challenged.  

 

Leave him alone, he was just trying to make a point.

[PilotManChase 0]

I am not sure if I had the same problem as you are describing, but I was flying the T7 YSSY-KLAX, and I had it set to fly while I was asleep.  When I woke up in the morning, my plane was going absolutely crazy.  It was spinning and displaying a number of warnings.

 

I am not sure what started this.  I always make sure that the AP is engaged when I leave, and I am careful not to touch the flight controls so as to not disengage the AP with a manual override.

 

Oh yeah, and my aircraft ended up over ANTARCTICA!  When I looked at the flight log from FSX, it looks to have been off course for a long time.  The farthest it goes back is to my aircraft heading southbound over New Zealand.  I should have never been around there.

 

I am also confident that I did not put the points in incorrectly.  Any ideas?

[Yosm 19]

Ive been following this forums since release and I haven' seen any mention so here goes. 

 

Im currently doing EGLL-VTBS with the following route:

DVR 5101N L9 KONAN UL607 AMASI UM149 BOMBI UL984 PADKA L984 FASAD B493 TIKNA A87 KEKAL N644 ABDAN LEMOD N644 DI A466 SAMAR M890 LLK R460 CEA L507 OSUKA DCTARONS

 

Now between OSLAN and BULIG on L984 airway the plane just decided to turn left off the magenta line and make the plane scream "bank angle bank angle". This is the 2nd time its happened, the first on EGKK-TBPB. Now I'm new to the plane and still learning things but I don't know what is causing this to happen. The magenta line is drawn properly and there are no discos.

 

Any ideas?

 

 

Had this as well. 

 

There already was another thread about this.

 

Replies were that it has to do with the winds of 3rd party weather engines.

 

If the winds are really though, say 70- 120 knots from either (left or right side) of the plane this banking will happen. 

 

This also happens when the aircraft comes above 83N in the sim. That has to do with the magnetic variation of the sim. The AP will get issues then.

 

That happened to me today. (that's why I found this topic)

 

While flying from VHHH to KSFO, already at cruise level, I noticed everytime the plane faces turbulence the A/P goes a little crazy, making huge turns.

 

When I was watching the Pilotseye.tv video of the Aerologic's 777, I heard the captain saying that it happens indeed with the aircraft eventualy, but he also said that keeping the autopilot engage, the aircraft corrects its course withing the limited bank angle.

 

As you said, the PMDG 777 is going beyond the 30° bank angle and triggering the alert. Also I found the aircraft really struggling to find its course back.

 

I dunno if it's a bug or we are doing something wrong. Maybe switching the bank angle limiter at the MCP from AUTO to 30 will correct this. I'll try that when it happens again.

 

For now, what I did to correct while it was happening was to switch to HDG HOLD mode, and when the wings were leveled I set a HDG course following the magenta line (LNAV) until leaving the turbulence zone, and then I finally back to LNAV/VNAV modes.

 

[mcbellette 145]

I turned off turbulence effects in FSUIPC - no more haywire autopilot when encountering turbulence or strong high level winds...