Zig zag lines

[Artox67]

Even after the update, flying in direction north causes issues with zigzag lines

EDLP - ESGG course 002 and the plane is flying like drunken.

[Artox67]

Update, 

looks like has something to do with the distance to the next waypoint

how closer I'm to the way point so less zig zag comes.

Distance was 209NM and at 80NM to the waypoint the behavior stops

[Danny Vincken]

Same here. After a sharp turn the autopilot has issues getting back on the centerline. especially with a crosswind or when the next waypoint is close after the turn.

[FreightDawg]

14 minutes ago, Danny Vincken said:

Same here. After a sharp turn the autopilot has issues getting back on the centerline. especially with a crosswind or when the next waypoint is close after the turn.

Watching a youtube vid lastnight and the pilot said after each turn to push in the heading button , havent tried it yet 

[Artox67]

Quick update again,

 

tested again and for me this happens only flying to the north between 358 and 002 degrees 

[DGH]

1 minute ago, Artox67 said:

Quick update again,

 

tested again and for me this happens only flying to the north between 358 and 002 degrees 

What wind ? 
 

because others posted other directions also

[Artox67]

Wind was ~23kn Tailwind

vor 4 Stunden , DGH sagte:

What wind ? 
 

because others posted other directions also

 

[DGH]

 

1 hour ago, Artox67 said:

Wind was ~23kn Tailwind

 

yeah that fits the symptoms 😬

[CH4PZ]

i experienced something like this yesterday, just would not follow NAV (zig zagging across flight path), but heading mode held true. cant remember heading but was north-ish 

[Artox67]

vor 58 Minuten, CH4PZ sagte:

i experienced something like this yesterday, just would not follow NAV (zig zagging across flight path), but heading mode held true. cant remember heading but was north-ish 

I flown yesterday 2 flight west and southbound with up to 80KN crosswind.

Everything was fine.

[vmironovich]

Have the same experience flying towards North, plane turning quite shraply to the left and then correcting. Wind 300/30. Had to switch to heading mode.

[CH4PZ]

On 4/2/2021 at 1:02 PM, Artox67 said:

I flown yesterday 2 flight west and southbound with up to 80KN crosswind.

Everything was fine.

ive since had 2 more flights with the Zig Zagging, an issue that wasnt there before update. currently happening on a northbound flight, so had to fly heading mode. basically cant use the plane atm

[FSHomeCockpit]

Is there a planned update to address this issue? Every time I fly the CRJ it zigzags and chases the NAV line on the PFD after turning. Usually it turns too sharply and undershoots the turn. Then zigzags to try to center itself on the line again. Eventually it settles down. Until the next turn... it's the only thing I find wrong / very annoying with this aircraft. Hopefully they plan to fix this?

[Puuhbear]

vor 8 Minuten, FSHomeCockpit sagte:

Is there a planned update to address this issue? Every time I fly the CRJ it zigzags and chases the NAV line on the PFD after turning. Usually it turns too sharply and undershoots the turn. Then zigzags to try to center itself on the line again. Eventually it settles down. Until the next turn... it's the only thing I find wrong / very annoying with this aircraft. Hopefully they plan to fix this?

Yes

 

[pbrad74]

2 hours ago, Puuhbear said:

Yes

 

Wonderful response...... Yes.

 

I have parked mine in the hanger and there it will sit, it's a shame. I'm starting to regret things. This single aircraft cost me almost as much as the sim itself. It would be nice if they actually fixed currently released aircraft before trying to release another aircraft or maybe even a pop into the forums letting us know that they are working on it. Communication is rather lacking

[Puuhbear]

vor 7 Minuten, pbrad74 sagte:

Wonderful response...... Yes.

 

I have parked mine in the hanger and there it will sit, it's a shame. I'm starting to regret things. This single aircraft cost me almost as much as the sim itself. It would be nice if they actually fixed currently released aircraft before trying to release another aircraft or maybe even a pop into the forums letting us know that they are working on it. Communication is rather lacking

Well actually there is a lot of infos about them fixing it. 

[FHSim]

 

 

AFTER THE UPDATE, STILL THIS, WHYYYY?????

[Secondator]

Hi FHSim,

Please post the full route that you ued and the leg where you saw the zig zag.

[FHSim]

1 hour ago, Secondator said:

Hi FHSim,

Please post the full route that you ued and the leg where you saw the zig zag.

oh god, i'll need to remake the flight, but i dont have any app to show my route  

[LesOReilly]

1 hour ago, FHSim said:

oh god, i'll need to remake the flight, but i dont have any app to show my route  

I think they just want the waypoints you put into the FMS.... So the Route and then they can load that into their sim and try it..

[FHSim]

8 minutes ago, LesOReilly said:

I think they just want the waypoints you put into the FMS.... So the Route and then they can load that into their sim and try it..

Oh, i have the FPL here, i'll sent here the  archive (is a flight from LFMN to EDLP. So, i took off with ZFW = 43tones and 10.1tones of fuel. FL350

LFMNEDLP (1).flp

[DFWSupertrooper]

3 hours ago, FHSim said:

 

 

AFTER THE UPDATE, STILL THIS, WHYYYY?????

 

Same here.  Seeing a lot of the wide turns (beginning 11 miles from the waypoint in some cases).  Also, three flights in and not one perfect approach (vertically).  The LOC locks in fine, and GS captures (according to the tell-tale green GS) but no vertical descent along the path.  Descent seems to just keep doing whatever you were doing prior to GS capture (same rate or level as may have been the case).  Throttle management is WAY better, but the ILS is simply not working as well as before and LNAV is off as this user indicates on/after turns then is fine.

 

Here were MY routes:

 

EDDB 25L LURO1N LUROS M725 HDO GOLOP VOZ LANUX RUPET GRZ PETOV PETO2Z 04 LDZA

 

ENVA 27 UTUN1W UTUNA ARTOR ALASA AGATI RIMET T157 KERAX KERA3R 07R EDDF

 

EDDL 05R DODE6Z DODEN Y853 BOMBI ESATI BARSU ENITA PEPIK NIT M748 ARFOX ARFO2H 31R LHBP

 

 

[Rafael Souza]

3 hours ago, FHSim said:

 

 

 

AFTER THE UPDATE, STILL THIS, WHYYYY?????

 

The same happens here to not says the problem with the throttle after this update!

Please fix that Aerosoft ! help me fly the CRJ again

[JRBarrett]

23 hours ago, DFWSupertrooper said:

Same here.  Seeing a lot of the wide turns (beginning 11 miles from the waypoint in some cases).  Also, three flights in and not one perfect approach (vertically).  The LOC locks in fine, and GS captures (according to the tell-tale green GS) but no vertical descent along the path.  Descent seems to just keep doing whatever you were doing prior to GS capture (same rate or level as may have been the case).  Throttle management is WAY better, but the ILS is simply not working as well as before and LNAV is off as this user indicates on/after turns then is fine.

I maintain avionics systems on real CRJs, and the autopilot can indeed begin a course change as much as 11nm before a waypoint. The limits are 7 nm for full bank mode, and 11 nm for half bank mode.
 

The FMS calculation of where a turn should begin is based on airspeed, the bank angle to be used and the number of degrees of course change required. At high airspeed, with a significant course change and limited to a fixed 12.5 degree bank, turn anticipation of as much as 11 miles would not be unusual. 
 

The actual CRJ autopilot is not very sophisticated in its lateral nav functions compared to something like a 737NG. Above 31600 feet, the CRJ can use only one bank angle which is 12.5 degrees, and it is “all or nothing” - the aircraft is either banked 12.5 degrees or it is flying level. It rolls into and out of banks at exactly 3 degrees per second, and that is also a fixed value. Below 31,600 feet it will normally use 25 degrees, but it can use 12.5 degrees if a minor heading change is required.

 

In the sim, the bank values are 30 and 15 degrees.

 

By contrast, a 737 autopilot can use multiple bank angles between 30 and 2 degrees, and it will often change the bank angle dynamically as a turn progresses based on required ground track, meaning that it can use less turn anticipation even on significant course changes.
 

The problem I occasionally (but not always) see, is that the autopilot sometimes rolls out of a turn too soon on a significant course change (before the FMS CDI centers) then works its way over to the new course by a series of bank/level bank/level maneuvers that could be described as “zig zagging”. The real CRJ autopilot by contrast can only use a constant radius turn initially, and will then level out on an intercept heading to the new course and hold that until the CDI centers. (More like the way a localizer intercept works). I am not sure how easy that would be to implement, as the aircraft has to use core MSFS autopilot functions behind the scenes, which is a current limitation one of the WT developers now working on the core sim discussed in a recent post on the MSFS forum.

 

The image below is the flight path of an actual SkyWest CRJ-700 on a flight from Fresno to Phoenix making a left course change at Palmdale VOR. It began the turn 10 miles before the waypoint, and did not fully rejoin the new course until 18 miles past the waypoint. The dashed blue line is the flight plan course (as you would see on the MFD), and the green line is the actual flight path.

 

Unfortunately, I cannot give you an answer on the glideslope issue. This was probably one of THE most intensively tested things I have ever been involved with as a beta tester. I myself sometimes did as many as 10 or 15 ILS approaches during a single session after the fix Hans came up with, and never saw it fail to begin descent or “lose” the descent path, which was a definite problem in the previous version.

 

 

 

 

[Andrea P.]

You definitely well express the issue. Simulated crj is commencing huge turns too early… this happens on both high and low levels. I frequently had issues with 90 degrees turns on STARs as well.

 

I definitely cross fingers to have this issue solved ASAP in some way, I don’t know how much is flexible or not the programming behind but would help just to adopt a correct Turn Anticipation Distance….