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Unable to follow the route properli in LNAV


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Just tried to fly a straight direct line over 60 NM and the Aircraft flew in LNAV a complete garbage route like in the picture. Should not be normal. Course was about 360 with a wind from 220/80.

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same experience here, today I also noticed that sharp turns on departures are very often ignored, so I must use DIRECT TO for CRJ to continue the plan

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vor 7 Stunden , shnt sagte:

same experience here, today I also noticed that sharp turns on departures are very often ignored, so I must use DIRECT TO for CRJ to continue the plan

Same here, sharp turns, marked with an arrow are often ignored, Flight Director stays centered.

Regards, Herbert

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vor 10 Stunden , shnt sagte:

same experience here, today I also noticed that sharp turns on departures are very often ignored, so I must use DIRECT TO for CRJ to continue the plan

 

Sorry, my mistake!

Selecting NAV before reaching 400ft AGL only arms it, but don´t activate it.

Now everything´s fine following sharp turns (mostly at SIDs).

Regards,

Herbert

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5 hours ago, Puukka said:

 

Sorry, my mistake!

Selecting NAV before reaching 400ft AGL only arms it, but don´t activate it.

Now everything´s fine following sharp turns (mostly at SIDs).

Regards,

Herbert

hmmm okay Ill try :D 

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Same experience for me, as OP, in first flight, switching to HDG resolves it, but that is not the answer obviously. Just searching for a solution.

 

It lines up on the Nav line correctly then the FD jinks to left, banking the AC to the left, then the FD jinks right banking the AC ro the right, like a Dutch Roll effect.

 

Dropped from FL310 to FL260 and it settled down, maybe the same issue the Longitude has?

 

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Same here. I think the whole AP in general is simply terrible. Poor LNAV performance, terrible altitude capture...Can’t fly it while it’s not fixed. 

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Yeah, I am facing a similar issue. I did the usual check to make sure I was not overshooting any waypoints, icing on, icing off, clear skies with elevated temps, elevation at 11,000ft and I eventually gave up and used the heading bug and it solved the issue. CoG is at 35%, keeping it under 270knts.

After several attempts, following the tutorial flights even...turning off all weather (no wind) it will still do this for me. Then sometimes it doesn't.

I have since left this in the hangar as the working title cj4 (newest) doesn't do this for me.

Right now I am flying from PHTO to PHNL just for a test and it keeps rolling back and forth, back and forth.

Then it stops for a few minutes.

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Same here, have followed all the advice (including hitting the load payload button multiple times) and still have horrible LNAV performance.  As OP posted, CRJ chases the flight path and swings back and forth.
 

This is such a show stopper and it surprises me how few of us are reporting this problem.  I've not seen any acknowledgement from Aerosoft that this is a bug and will be addressed.  So I continue to wonder if it's something I'm doing on my end? I'll continue to monitor this thread but until then I will park the CRJ and hope for a resolution.

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Yeah, it is tough if you've followed all the advice in all the posts about LNAV issues.

I had the swinging on my first or second ever flight and only after the IAF but haven't had it since. I was also making a lot of mistakes on the first few flights but I can't remember what they were now to be able to say anything useful. I know one was not arming Approach mode early enough when I was stable and near the appropriate altitude. I'd get too focused on trying to get the VNAV path right I'd lose focus on every thing else.

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Yes, this can be observed.

I can see that sometimes it just turns too early, flies perpendicular to new course for a moment, then turns towards the desired path, overshoots it, turns back again and so on. Until it finally manages to catch proper flight path.

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Same here 

 

EHAM-ENBR ( ENBR landing with strong tailwind because RWN17 gives CTD when selecting in FMC ) 

 

Noticed it started when I had a strong tailwind in a certain degrees angle.

 

No problem first 30 minutes of the flight.

Then I was at a waypoint and I was flying like 020 degrees and the wind was 230/50 ( something like that )

 

Plane kept flying with slight left bank to compensate.... after 10 seconds it "could not longer hold" and overcorrected to the left ( HARD ) .. and back again to the right. Then it started over again with the slight left bank compensation etc etc etc .

I could clearly see ( slight bank ) it was struggling with the wind and it passed a certain "stress level " and overcorrect.

This happened 6 to 10 minutes ( same as picture posted in first post )

 

THEN I was at a new waypoint and the plane change course to 330 degrees.

So the angle of the wind hitting the plane changed ... and did not have the issue the rest of the flight ( 45 minutes )

 

The thing that strikes me is that the angle and wind was almost the same as initial post !!

I bet it is a certain degree of crosswind that is causing the wobble

 

 

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I think the picture is around 5 to 7 minutes of flight vissible. It struck me so i took the picture in case it happens more often. But did not dig deep. 
 

little navmap in this case is continually updating. This screen was taken between Netherlands / norway above north sea

 

i will check if i can find out what scale it was.

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4 hours ago, DGH said:

I bet it is a certain degree of crosswind that is causing the wobble

I wouldn't doubt it. The Asobo AP had issues depending on wind direction too. I think they were fixed but I'm not sure. Before the CRJ I didn't use AP a lot.

Last time I checked Asobo still has fast shift in winds speeds but I haven't looked since the new wind UI was added. I always figures it was the broken wind "frequency" slider. But if wind gusts are changing unrealistically fast then an accurate AP might not be able to cope well with it. Just a thought.

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Having same issues,  constant s-turns while trying to fly in NAV mode at cruise.

Attached image is from Sim Toolkit Pro.  Flying at FL290 M.76  256/100  left/rear quartering wind

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Hi Captains,

i am seeing the same issues with LNAV. In Climb, Cruise and Descent..., but not always.

 

I am also seeing the aircraft turning wrong directions on SIDs from time to time.

One excample from yesterday .

 

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LGAV via the IDIL1B  SID

 

Aircraft turned Left instead of following the SID to the right.

 

but Back to Topic. LNAV definetly needs some more love either from ASOBO or Aerosoft ....

(ILS and throttles as reported in other threads, same issues)

 

other than that aircraft seems to behave very well after the mentioned workarounds (CG, Fltmodel etc ...)

 

Oliver

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If you look at the weather in MSFS and the wind graphs, you see that they always add turbulence in form of a sinus wave to a defined wind. So having 80 or 100 kts crosswind constantly modulated results in this swing.

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24 minutes ago, metzgergva said:

If you look at the weather in MSFS and the wind graphs, you see that they always add turbulence in form of a sinus wave to a defined wind. So having 80 or 100 kts crosswind constantly modulated results in this swing.

This is what I thought.  One of the reasons I thought we saw this kind of AP behaviour more in MSFS is because so many main runways have massive crosswinds. Completely unlike real life. That is just one part of it of course.

This, to me, means it is an MSFS problem because we can see that the aircraft is tracking fine and on approaches where the crosswind is more normal, it tracks great. The issue appears to be that its path is being unnaturally disturbed.

 

I know people want Aerosoft to fix this but personally I'd prefer the sim itself to be fixed so we fix some of the behavior of the other aircraft in the store. Asking each aircraft maker to fix a sim problem isn't very productive.

 

My hope is that some of these issues will increase the priority of wind fixes at Asobo. It has always been my #1 dislike with the sim. It is broken in so many ways.

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1 hour ago, metzgergva said:

If you look at the weather in MSFS and the wind graphs, you see that they always add turbulence in form of a sinus wave to a defined wind. So having 80 or 100 kts crosswind constantly modulated results in this swing.

I doubt this is the cause because it stops happening as soon as you switch to Heading mode. Resetting the AP (Cycling FD off and back on) also tends to fix it.

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