FBW A320NX Custom Violent Pitching

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1

I’ve done several flights with the Experimental version ( use Thrustmaster Stick/Quadrant). The flights are flawless regarding take-off and during crz. I capture the LOC and click on APR and then it captures as normal and flies the GS as normal.
About half way down the GS, it starts pitching up/down violently and then about 600FT RA, it settles down.
This happens on AP in normal Approach mode, and also in AutoLand mode with AP2 switched on. Landing manually without AP is ok.

I keep the A320NX updated everyday, and have also checked the TCA stick for any weird bindings and also checked dead zones.
I create my plans via SimBrief and everything is set up as its supposed to be in the MCDU.

The one thing I have noticed is that it always happens half way down the GS and at any airport. Apart from that it flies great, and I never had this problem with the old Custom version that I used to fly.

I’ve even deleted the old folders and re-installed from the Installer this morning.

Any one else having this issue?

2

You mean something like this? I always thought this is just turbulent winds.

3

Mine’s a lot more violent than that. Yours appears to be just turbulence. When it happens to me, its so violent I sometimes get a stall warning for a brief moment until it settles downs!

I will do another flight today, and record it. I’ve flown the FBW since day one, and always used the Custom version with no issues at all. Since using the new Experimental version, this always happens now.
At least I’m getting practice on manual landings lol

4

Ahh okay… I always livestream my flights directly to my YT channel, so every event that’s happened in my flight from the start to finish, I always have a recorded evidence of it.

5

Just checked FBW’s github page, and another user gets the same issue but at around 16,000ft with the same violent pitching. He posted a video…

The pitching starts about 5.40 mins into the video. He’s lucky, mines start half way down the GS, I’m lucky I haven’t hit the ground yet lol

The github pages states that it “Won’t Fix” for some reason.

6

Just in case you might have a conflicting mod, have you tried temporarily emptying the Community folder and attempted more landings?

7

Huh… this reminds me of the old issue with the violent rolling left to right. One that was mitigated by turning off the autopilot, wait for it to stabilise, then turning it on again.

Or by turning off the SEC switches.

It’s also similar to the issue with the Cessna Citation Longitude that I experienced last year.

Could it also be a Deadzone or Flight Model setting issue?
I also found a wing-flex mod in flightsim.to earlier, one that was claiming to be compatible with the A32NX mod, but since it’s modding the flight_model.cfg I’m doubting that claim.

8

It sounds like the aircraft is trying to home in on a too tightly specified altitude and is therefore constantly “overshooting” and having to adjust again, in the opposite direction. This would cause oscillation around the altitude the aircraft is aiming for at the ever changing distance from touchdown and lead to what you are experiencing. A bit like a feedback loop if you like.

What is causing that for apparently just the OP though, is more of a mystery.

9

I’ve just done another flight and as usual with all my flights I use SimBrief. Every thing in the MCDU is fully added in (I’m an avid fan of EasySim Pilot on youtube!).

I’ve completely emptied my mod folder except for the A320NX. Experimental version 8d09903 is installed.
Now the video below is fully autoland and i was hands off on the stick until i had to grab it to stop the AP from steering me on the grass!

Am I doing something wring here? This happens even without autoland and just using the AP APR approach.

10

Hmmm… the LAND mode isn’t triggering. It should trigger LAND mode at 400 AGL.

11

In all three videos the pitching seems to start as soon as the framerate becomes awfully low.
Maybe it’s related.

@Neo4316 there wasn’t any flare or thrust reduction either. Strange indeed.

12

I noticed this as well on my flights. May be this is a coincidence on this one flight (EETN), but after watching my own video again, it looks like it started when the OM indication started.

13

Hm, sounds like the old X-plane “sim rate” issue where the sim couldn’t keep up with the aerodynamic calculations if the sim rate dropped below a certain value. He could test that hypothesis by lowering the graphics settings to LOW and see if the same issue happens.

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14

This weird pitching occurs the whole time.

At 2:30 the fps seems to be a bit higher and the pitching almost stops. At 2:35 serious stutters start and the pitching as well.

Would be nice to know why the autoland didn’t work. I couldn’t see any error in the setup.

15

There was no stuttering/pauses during the approach. The video\audio clipping was the xbox video capture, it does it all the time lol.

16

That’s bad news in this case…

17

The plane was still in LOC* and therefore LAND did not engage. In that case you need to go around…

18

Good catch :+1:, but that’s a weird combo. GS and LOC*

19

It is, but this happens when not in AutoLand mode and the LOC has been captured.
I’m just doing another flight now LFPG to EGCC and i’ll record it gain.
I’m determined t get to the bottom of this problem, I just love flying the FBW :grinning:

20

Well, I’ve developed it and did so many landings. So I know it pretty well.

I’ve noticed that the LOC* has sometimes issues capturing it - in certain situations.

I have it already in the list to redo the LOC* law, but things need to settle a bit. It was a very intense time to develop all that you have now in hands.

It’s nice to see so many people having a lot of fun with it!

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