C-172 autopilot question.

Post any technical issues here. This forum gets priority from our staff.
yotapimp
Airman
Posts: 18
Joined: 07 Nov 2013, 18:44

C-172 autopilot question.

Post by yotapimp »

Hey guys I just have a question about the autopilot in the c172. I just happened to notice that no matter how bad the cross wind is the autopilot will keep the heading perfect but it can't hold the alt. It climbs and dives 500 to 1500 with or without wind. I'm just wondering is that how the real autopilot works? Does it really hold the heading no matter what but can't hold the alt? Thanks!

User avatar
lonewulf47
A2A Chief Pilot
Posts: 6744
Joined: 03 Aug 2008, 10:41
Location: 1 NM east of LSZH

Re: C-172 autopilot question.

Post by lonewulf47 »

Try to find your answer here: http://a2asimulations.com/forum/viewtop ... 08&t=37427 Actually there is NO issue with altitude hold as long as the autopilot is handled according to the manual and no incampatible trim assignment is used - just like the real one ... :D
Oskar

ASUS MAXIMUS XI Hero, i9-9900K 8 Core OC 5.2 GHz, WIN10-64Bit, 32GB DDR5, Nvidia RTX 2080 Ti Strix, 2x 2 TB SSD M.2, 1x 2 TB SSD, 1 monitor 4k, AS4, EFB on remote PC

Image

yotapimp
Airman
Posts: 18
Joined: 07 Nov 2013, 18:44

Re: C-172 autopilot question.

Post by yotapimp »

Thanks but I have read the manual many many times and I've read all the other post about the autopilot I could find.

User avatar
Lewis - A2A
A2A Lieutenant Colonel
Posts: 33284
Joined: 06 Nov 2004, 23:22
Location: Norfolk UK
Contact:

Re: C-172 autopilot question.

Post by Lewis - A2A »

If this is whilst on the Glidescope then there is an issue that has been fixed for the next release.

thanks,
Lewis
A2A Facebook for news live to your social media newsfeed
A2A Youtube because a video can say a thousand screenshots,..
A2A Simulations Twitter for news live to your social media newsfeed
A2A Simulations Community Discord for voice/text chat

yotapimp
Airman
Posts: 18
Joined: 07 Nov 2013, 18:44

Re: C-172 autopilot question.

Post by yotapimp »

I'm sure a2a will get all the little problems fixed before to long. I'm not to worried about it. It's still an amazing plane.

THibben
Staff Sergeant
Posts: 257
Joined: 16 Oct 2007, 16:06
Location: Lacey, Washington

Re: C-172 autopilot question.

Post by THibben »

Hi Lewis,

Is there a reason the autopilot porpoise problem fix can't be released separately? It sure would be nice to get it behind us.

Thanks,

Tom

User avatar
Lewis - A2A
A2A Lieutenant Colonel
Posts: 33284
Joined: 06 Nov 2004, 23:22
Location: Norfolk UK
Contact:

Re: C-172 autopilot question.

Post by Lewis - A2A »

Hello Tom,

we are getting a core update together so we can get that out to you guys and get the C172 where it belongs in the core system.

thanks
Lewis
A2A Facebook for news live to your social media newsfeed
A2A Youtube because a video can say a thousand screenshots,..
A2A Simulations Twitter for news live to your social media newsfeed
A2A Simulations Community Discord for voice/text chat

Rory
Airman
Posts: 10
Joined: 02 Nov 2013, 12:37

Re: C-172 autopilot question.

Post by Rory »

yotapimp wrote:Hey guys I just have a question about the autopilot in the c172. I just happened to notice that no matter how bad the cross wind is the autopilot will keep the heading perfect but it can't hold the alt. It climbs and dives 500 to 1500 with or without wind. I'm just wondering is that how the real autopilot works? Does it really hold the heading no matter what but can't hold the alt? Thanks!
I will quote Welsch here because its a great starting point to find the problem, he said :

Have you checked your frame rate? For me these problems exist (and they are severe when I do encounter them) only when my flight sim struggles too much.

I can get away with some quite low frame rates when using simple planes like the ones that come with FSX. But the A2A Cessna needs a bit more power - my (temporary) solution has been to set the process priority of FSX.exe to "High" in the task manager - that apparently diverts enough extra processing power to the sim so that the autopilot performs as it should.

yotapimp
Airman
Posts: 18
Joined: 07 Nov 2013, 18:44

Re: C-172 autopilot question.

Post by yotapimp »

I have turned my frame rate to under ten and I still have the ap issue. I also have already set fsx to high priority. It does help but I still get the climbing and driving

User avatar
Oracle427
Chief Master Sergeant
Posts: 3916
Joined: 02 Sep 2013, 19:30
Location: 3N6
Contact:

Re: C-172 autopilot question.

Post by Oracle427 »

The frame rate needs to be above 20. Under 10 is very poor not just for the sim performance but also for your ability the control the aircraft.
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

yotapimp
Airman
Posts: 18
Joined: 07 Nov 2013, 18:44

Re: C-172 autopilot question.

Post by yotapimp »

I've set it to 30 25 20 and 10. There is no change on any frame rate.

User avatar
Oracle427
Chief Master Sergeant
Posts: 3916
Joined: 02 Sep 2013, 19:30
Location: 3N6
Contact:

Re: C-172 autopilot question.

Post by Oracle427 »

yotapimp,

You don't "Set" a frame rate. You need to adjust the graphics and AI traffic and scenery settings in order to optimize your simulator. The frame rate you are getting is "roughly" displayed in the shift-z display.

I believe you have to press shift-Z twice to pull up the frame rate.
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

yotapimp
Airman
Posts: 18
Joined: 07 Nov 2013, 18:44

Re: C-172 autopilot question.

Post by yotapimp »

I use the one in te fsx setting but ok ill go setup it up right now and get a frame rate around 20. Thanks Oracle

yotapimp
Airman
Posts: 18
Joined: 07 Nov 2013, 18:44

Re: C-172 autopilot question.

Post by yotapimp »

I'm on fsx right now and I have a new problem. My avionics wont turn on.

User avatar
Oracle427
Chief Master Sergeant
Posts: 3916
Joined: 02 Sep 2013, 19:30
Location: 3N6
Contact:

Re: C-172 autopilot question.

Post by Oracle427 »

yotapimp,

I do not understand what you plan to do. I think you were initially changing the "target frame rate" in the FSX graphics settings menu.

You will need to reduce the other settings such as reducing filtering upwards potentially all the way to "none".

Disabling Lens Flare and Light Bloom will also help a lot.

On the Aircraft tab turn off all the checkboxes except for High resolution 3D Cockpit as that is required for the A2A 172.

On scenery turn down the water effects and the autogen density sliders, ensure scenery shadows are off.

All the traffic tab set everything to 0% (off)

Then run a test and see how well everything works.

If you find that the AP now functions well and I sure hope it does, you can proceed to increase the settings again a little at a time to see at which point performance degrades unacceptably.

I would not increase anything on the traffic or the water effects and autogen density on the scenery tab until you are happy with the other settings.

Good Luck!
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

new reply

Return to “C172 Trainer Tech Support”

Who is online

Users browsing this forum: No registered users and 7 guests