Autopilot issue

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DomiMili
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Joined: 14 Mar 2021, 19:28

Autopilot issue

Post by DomiMili »

I have a little issue which I hope someone could help me with. In C172 when I turn on the autopilot (yes, shoots up, but that's fixable, by clicking altitude hold or something) what is not fixable though is the heading. If I turn off wing leveler and turn on NAV or HDG it starts to turn fine, but it seems to overcorrect and then go back. This oscillation increases every time so I have to turn off the HDG. My FPS is about 11 is that the problem? Or am I missing on something? This is very important because I'm doing a world tour in this beautiful model, but I don't want to hand fly it all the time as I'm doing it right now. Thanks for any tips

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Nick - A2A
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Re: Autopilot issue

Post by Nick - A2A »

Hello and welcome.

I'm afraid that the degraded autopilot performance is indeed likely to be a result of the low FPS that you mention; ideally you want FPS to be 18 or above.

Are there any settings you can change within whatever sim platform you use to increase performance a bit? If you give us more details on your PC and sim setup, we may be able to make some suggestions. A round the world trip at 11 FPS sounds like a rather painful undertaking!

When you mention the aircraft "shoots up", one general tip with regards to the autopilot is to make sure the aircraft is properly trimmed before you engage it.

Thanks,
Nick
A2A Simulations Inc.

DomiMili
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Posts: 38
Joined: 14 Mar 2021, 19:28

Re: Autopilot issue

Post by DomiMili »

Thank you for your reply. My specs for FSX: AMD A8-7410 APU with AMD Radeon R5 Graphics 2.20 GHz 4GB RAM Windows 10. Before using A2A Cessna, I was using pretty high settings. Now I had to step back a little to medium settings, so there is a possibility to go on lowest. Even though 11 FPS isn't a big issue for me, I wouldn't be able to do it completely without autopilot or just wing leveler.

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Nick - A2A
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Re: Autopilot issue

Post by Nick - A2A »

Okay, thanks for the info. I'm not too familiar with the performance of these AMD components so a bit of experimentation with settings may be the best bet. FSX is quite CPU dependent so reducing sliders for things like auto-gen is probably a good place to start.

Also, please make sure you run the Accu-Sim update for the 172 if you haven't already done so.

Cheers,
Nick
A2A Simulations Inc.

DomiMili
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Posts: 38
Joined: 14 Mar 2021, 19:28

Re: Autopilot issue

Post by DomiMili »

Hello, sorry for late response.

I tried to reduce the number of scenery objects, which didn't help at all. The FPS was about 1 higher for bad scenery. But I tried the autopilot anyways even with autogen and it seemed working (thx for the trim suggestion) even the HDG seemed ok. BUT when I was flying today, the heading wasn't working again. Is there a possibility that some kind of magnetic interferrence could occur, since I'm flying in Greenland (the only point to get to Europe) ? The working test flight was somewhere in USA btw. And there is another, much severe issue. After some time some very strange zooming action happens. It zooms in and out and it can't be stopped. Only in virtual cockpit. The frequency changes randomly. This will continue for about 3 minutes and then change to black screen. After a moment FSX will crash. I managed to prevent the crash 2nd time by saving the flight after blackout and immediately reload it. I am 90% sure this is caused by the autopilot since this happened after 2 hours of flying, then after 40 and then only 15. After that, I didn't turn on the autopilot (before using with wing leveler) and happily flown another 2,5 hours without a single zooming.

P.S. the default photo in FSX using "V" also doesn't work, it only shows black screenshot (I uninstalled my HDR addon, and it works with other planes)

Thank you for your time

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Nick - A2A
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Re: Autopilot issue

Post by Nick - A2A »

Thanks for the additional info DomiMili, sorry for the delayed response also!

I'll start with the "strange zooming action" because that's the easiest one to resolve. It's simply the hypoxia simulation and the fix is to reduce your altitude without too much delay. For info, the hypoxia modelling begins to have an effect at altitudes over 12,500 ft. However, you can get up to 14,000 feet for 30 min or so as well.

For the autopilot issue, unfortunately I think it's likely you'll continue to see slightly erratic performance if the FPS is only around 12 or so. Do you have any other add-ons running alongside the 172?

Regards,
Nick
A2A Simulations Inc.

DomiMili
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Posts: 38
Joined: 14 Mar 2021, 19:28

Re: Autopilot issue

Post by DomiMili »

Hello, thanks for the hypoxia solution. My only addons running are FSUIPC with FSXWX weather engine, I someimes use landing rate monitor, but that has no effect on the autopilot. Any suggestion why the screenshot option (the final picture) shows black screen?
Thanks

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Nick - A2A
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Re: Autopilot issue

Post by Nick - A2A »

Were you trying to take the screenshot during the hypoxia event, or does this happen at any time?

To be honest, given the issues you describe it might be worth resetting FSX back to its default settings, checking your FPS performance and then adjusting sliders as required. The FSX.cfg can be found in the folder below, and if you back up this file and then delete it, FSX will generate a new default copy.

C:\Users\[UserName]\AppData\Roaming\Microsoft\FSX\FSX.cfg

Thanks,
Nick
A2A Simulations Inc.

DomiMili
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Posts: 38
Joined: 14 Mar 2021, 19:28

Re: Autopilot issue

Post by DomiMili »

That happens any time, I will try to move the fsx.cfg, any other ideas to boost fps? It got better when I decreased the water quality, but still not at 20 fps with the a2a planes, only default cessna, and yes, I understand it's quality, so it's more computer demanding

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Nick - A2A
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Re: Autopilot issue

Post by Nick - A2A »

The topic of FPS in FSX is a huge one, but if you can let us know what fps you see with default settings, we'll have a better idea of your system's capability.

For the screenshot issue, are you using FSX in windowed or full screen mode?

Thanks,
Nick
A2A Simulations Inc.

DomiMili
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Posts: 38
Joined: 14 Mar 2021, 19:28

Re: Autopilot issue

Post by DomiMili »

For the screenshot issue: I am using FSX in windowed mode to be able to swith to other apps like Spotify or Littlenavmap to see info on VOR's etc.
I think I might might be able to figure out the FPS issue on my own, even though I don't think the autopilot isn't working because of that.
If it's not the magnetic interference in Greenland, I found out it's possible for the HDG to work if I don't adjust the compass (I'm doing it by pressing D) may this be a problem?

DomiMili
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Posts: 38
Joined: 14 Mar 2021, 19:28

Re: Autopilot issue

Post by DomiMili »

Quick FPS update I installed new FSX to another folder to find out default frame rates, And yes, they were a lot better, though, but considering it was default cessna, not too good (about 30 or so) what I figured out instead is when I was trying to reduce flickering of water that somehow appeared maybe due to ENVTEX I wanted to try. So, I lowered water settings to none and I got about 120 stable FPS going to 140 at times CRAZY, I will try to replicate this with slightly higher setting in my default FSX, also the water looks more realistic, not like a mirror.
And I found out my FSX/texture folder has interesting amount of files from /scenery/world/texture folder, so I hope it won'T break any addons when I replace it with my new FSX texture folder

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Nick - A2A
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Re: Autopilot issue

Post by Nick - A2A »

Sounds like you're making good progress with reviewing your settings for better framerates which should help the autopilot algorithm work reliably. You'll still need to make sure the compass card is regularly corrected and the heading bug set properly for it to work as designed though.

For screenshot capture, try experimenting with fullscreen mode too; switching between modes should only take a second or two.

Thanks,
Nick
A2A Simulations Inc.

DomiMili
Airman
Posts: 38
Joined: 14 Mar 2021, 19:28

Re: Autopilot issue

Post by DomiMili »

Hello again,

I'll give a little update of what's happening. I uninstalled ENB completely because of it's FPS impact and I wasn't using it. The screenshot is still not working on the 172. It is on 180, J3 and every other plane as far as I know. That is not good since I want to capture some moments on final and using PrtScr isn't an option. I'll try some addons, maybe that could solve it.

With the autopilot issue. It is still happening, even though it worked a few times. I still do think it might be due to me being close to poles in Norway now. I checked the manual and the gyro shift is set for "realistic" as it should. This weird movement is not happening if I use GPS mode though, which is interesting. The GPS works fine, NAV doesn't, neither with heading select nor with using VOR.

What I also find weird is the ADF, I might be wrong with this one, but it seems slow in responding. It even shows bad direction for a while, the it slowly goes to the right one. While turning, it doesn't show the right direction immediately, you need to wait for it to establish and it's not anywhere fast.

Thanks for any other ideas.

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Nick - A2A
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Posts: 13728
Joined: 06 Jun 2014, 13:06
Location: UK

Re: Autopilot issue

Post by Nick - A2A »

Hello,

What method are you using to capture screenshots DomiMili? If it's a keystroke, are you sure it's not mapped to something else in the 172 via the input configurator or a profile in other software such as FSUIPC?

Some screenshots of what's going on in the cockpit would certainly help us to understand what's going on with the autopilot.

Thanks,
Nick
A2A Simulations Inc.

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