1.9.5.0 - autopilot dolphin dance (oscillations) still an issue

As I pointed out in the original post, I get severe oscillations in the Longitude regardless of whether I use VS mode, FLC mode or even just ALT hold mode. Using VS mode instead of FLC does appear to help in the CJ4 and 747-8 though.

I haven’t overclocked any of my hardware or done any other unusual tweaks.

Not working for me.

What confuses me, is that the Longitude’s AP was working just fine when the sim was released. Something was done in the 1.9.3.0 patch that screwed it all up. I don’t get why it is so hard for them to figure it out…

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Yeah, I’m really curious how they messed that up and why they couldn’t revert it to an earlier state. Perhaps it’s the result of other important changes and more complicated than we think.

There is also the “dolphin dance” Bug at the Beechcraft Air 350i, you can try with VS Mode ca. 1400ft/min , starting from ca. 26.000ft to 34.000ft (official cruise height), it is also if you use only Althold mode, so unuseable for long trips. pitch is completely dancing crazy, thats not normal! The plane can also crash during overshoot.

Flight Simulator Version 1.9.5

See my Video:

Dolpin Dance Beechcraft 350i Pitch oscillations

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Thanks for sharing this. I’ve linked to your post in the original post.

Yes, the avionics code is pretty much all shared between aircraft, depending on the avionics it has.

OMG … Not flown the MSFS King Air yet … I was saving the Potential disappointment till maybe Christmas, in the hope that ASOBO would have fixed it by then.

I am no Aeronautical Engineer, but looking at it reminds me of how a Kite flies.
Little tail, it vibrates about at a high frequency.
The Longer the tail, the more stable it becomes, and the lower the frequency,

My gut feeling would be that anyone who has studied Aeronautical Enginnering, even maybe a 2nd year student, might well be able to tell exactly what is causing that.

Embry-Riddle Aeronautical University

(https://erau.edu/) – where are you guys when you are needed ???

If it’s not fixed by Aug 2021, there will be lots of knowledgeable people at Oshkosh 2021 who should be able to explain why this is happening
( Assuming there is an Oshkosh 2021 :small_airplane: :airplane: :rocket: :helicopter: :parachute: )

As well as the ASOBO King Air, the ASOBO C172 & C150s are also pitch unstable, but not as much a the King Air. Maybe its gets worse at altitude?

My point here is, The Carenado CT182 is “ROCK Stable” and the AP seems to be tuned very well to match the plane. It is really “TIGHT” and “Positive”

So whats is Carenado doing …??
That’s their secret, locked up in their protected Encrypted configuration files :frowning:

yes from 26.000 ft it gets worse and worse… should i report it as a bug to Zendesk or do they read our reports in this forum anyway? Thanks in advance!

With my limited Aeronautical Engineering knowledge, that would seem to make sense.
The higher you go, the more unstable it becomes – the air is getting thinner.

If it is bordering on instability at ground level, it might not be surprising, that at higher altitudes, it gets worse.

All of this is why the game has been uninstalled for the time being. I’m glad it was included in Game Pass, which has to be the best deal in gaming out there, but I would have been pretty upset if I had actually paid for this separately. I’ll be lingering in the background to see when all of the major bugs get worked out, then maybe I’ll come back and give it another chance. Hate to say I’m disappointed in this release. It’s both amazing and disappointing at the same time. Oh well, I have no doubt they’ll get things fixed eventually. Until then, I’ll be flying around in DCS World where I actually enjoy the flight characteristics and complexity.

Please try my sailplane models (converted from Wolfgang Piper) on http://www.andreadrian.de/FS_2020_sailplanes/index.html and tell me how you like the airplane behaviour. Everybody can read the configuration files of these airplanes.
The problem - not only with airplane simulation - is, many parameters are dependent on each other. You not only have to know what the parameter does, but more important how the parameters interact. I think the Asobo programmers have still a long way to go. I do not think that the reason for the poor behavior is the simulator engine, it is the configuration of this “numerical integration beast” that makes the dolphin dance.

I agree with you // The Carenado CT182 flies much more realistically, especailly compaired with the similar ASOBO planes, C172

Yes I found it impossible to trim the higher performing aircraft to fly straight and level. I thought it was just my lack of skill…

EXACTLY … I have also been saying the exactly same thing, since the day the Sim was released !!!

Highly Unstable “Dynamic pitch stability” in most/all the Asobo aircarft.

and its not necessarily the actual SIM itself.

The Asobo GA Cessna’s are VERY highly pitch unstable.
The CARENADO GA Cessna is far more stable, and is Realistically Trimable, and stays trimmed without oscillation.

Unfortunately the Carenado’s .cfg files are Hidden/encoded, so it is not obvious what they did to make their plane stable :frowning:

@ASOBO

Maybe if I post this Graphic enough times, someone at Asobo will take some notice !!!

And this is Exactly what Asobo did in the last patch #4. Altered the AP’s control loop period, to try to improve the plane’s Dynamic Stability

( but that only appears to cover up the real cause of the issue, and only when the the AP is on)

It does NOT fix the “Root Cause”

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IS IT JUST ME?

https://forums.flightsimulator.com/new
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No. I have the dolphin dance with sailplanes (airplanes without engine) I converted from FSX.

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Since the patch yesterday, I’ve made long trips in the TBM and the Longitude.

The Longitude still porpoises a little bit during climb at low altitude, but nowhere near as much as before. At cruise it is stable, altitude wise. But Nav mode tracking is off, and it seems to hunt the heading a little. Not nearly as bad as the 747, but you are in a constant slight bank one way or another. I would consider it livable, but still needs work. My biggest issue with the Longitude is the fuel burn. 7 hours endurance??? Yeah right, maybe sitting on the tarmac at idle - at cruise I ran out of fuel in less than two hours.

I did a long flight in the TBM today (Bordeaux to Reykyavik). ALT HOLD, FLC and V/S modes all worked perfectly. No porpoising. Occasionally it would slowly drift up to 20 feet or so above or below the target altitude, but the it would slowly come back. No big deal.

The TBM’s NAV mode worked fine, except for one time it seemed to forget the flight plan and kept going straight, missed a turn. Turned NAV mode off and then back on, and it came right back, so just a little glitch.

Who knows, maybe in 6 months or so we’ll have properly working autpilots in all the planes. They really need to work on the 747 - that’s a dog’s breakfast.