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777 Autopilot Glitch

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777 Autopilot Glitch

Postby japanair772 » Tue Aug 22, 2017 8:15 am

Hi,
I have 2 questions.
1. When I fly the 777, I engage the autopilot. Sometimes the autopilot makes the aircraft go left and right. Why does that occur?
2. Sometimes if I fast forward it the aircraft (with LNAV on) does a 360-degree circle and goes back into the route every 5 minutes or so.
How can I fix it?
(Ps. I cannot edit the livery on the 777 and the 757,744 why is that?
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Re: 777 Autopilot Glitch

Postby Octal450 » Tue Aug 22, 2017 2:09 pm

Sounds like the autopilot needs to be retuned.

Can you provide more details on the phase of flight?

Kind Regards,
Josh

PS: this subforum is for developing autopilots. You should use Support/Flying/Autopilot instead.
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Re: 777 Autopilot Glitch

Postby Clive2670 » Tue Aug 22, 2017 5:11 pm

it0uchpods wrote in Tue Aug 22, 2017 2:09 pm:Sounds like the autopilot needs to be retuned.

Can you provide more details on the phase of flight?

Kind Regards,
Josh

PS: this subforum is for developing autopilots. You should use Support/Flying/Autopilot instead.

Nice one Josh!!.....Saying "Autopilot needs to be returned" Reminded me of Otto the autopilot in the movie Airplane
My thoughts were a bit like the movie where the stewardess pulls out the inflation device because Otto keeps losing air and starts to blow him up to get him working again!!! Sorry your phrase just made me smile!! :D :D :D :D
All joking aside I have found that on the autopilot as well, beyond 4X simulated speed, Not that I'm bothered because realistically there is no real need to speed up the Sim' Dare I suggest this? But maybe to try and gain extra hours on a certain tracking program? Hope this doesn't re-open the little debate that started on another thread, that was closed and locked be a moderator about 2 weeks ago!!!
Thanks Clive aka: G-BLS01
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Re: 777 Autopilot Glitch

Postby Octal450 » Tue Aug 22, 2017 6:04 pm

@Clive2670 Yup. that part made me laugh!

Well, I'd be happy to retune the autopilot. This would be rewriting most of the PID controllers, and adding my attitude sync system for smoother engagements, and my better flight director. I got a request to do this in the past, but forgot to.

A stable autoflight for me runs up to 8X OK. (On my system)

Kind Regards,
Josh
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Re: 777 Autopilot Glitch

Postby Octal450 » Wed Aug 23, 2017 3:41 am

viewtopic.php?f=4&t=21870&p=317171#p317171
OK here is a new autopilot controllers I made.

Please give it a try @Clive @JapanAir772

Kind Regards,
Josh

PS: She does work in 8x beautifully :D
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Re: 777 Autopilot Glitch

Postby Bulldog 1 » Wed Aug 23, 2017 9:27 am

japanair772 wrote in Tue Aug 22, 2017 8:15 am:Hi,
I have 2 questions.
1. When I fly the 777, I engage the autopilot. Sometimes the autopilot makes the aircraft go left and right. Why does that occur?
2. Sometimes if I fast forward it the aircraft (with LNAV on) does a 360-degree circle and goes back into the route every 5 minutes or so.
How can I fix it?
(Ps. I cannot edit the livery on the 777 and the 757,744 why is that?


1- Maybe wind
2- No idea sorry mate
Training on the ground, to flight on the skies.
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Re: 777 Autopilot Glitch

Postby beef71 » Sun Aug 27, 2017 8:28 pm

Anyone else had their 777 fly perfectly fine and then when in Auto Land mode it either misses the runway or turns hard right about 20 feet off the ground (causing a crash)?

For example, yesterday on an Auto Land I was flying into KSFO on 28R...all lined up...except not...and landed in the bay.
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Re: 777 Autopilot Glitch

Postby wkitty42 » Sun Aug 27, 2017 8:46 pm

ILS auto-landings are not possible at all airports... this is because the beacons are located off the side of the runway instead of in line with it... KSFO's 28R is one of these as can be seen in the CTRL-M map with the line indicating that ILS path is off to the right of the runway out past the taxiway...
"You get more air close to the ground," said Angalo. "I read that in a book. You get lots of air low down, and not much when you go up."
"Why not?" said Gurder.
"Dunno. It's frightened of heights, I guess."
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Re: 777 Autopilot Glitch

Postby Hyde » Wed Aug 30, 2017 11:25 pm

KSFO 28R has ILS 111.70Mhz and LDA 110.75Mhz. LDA is used when SIMULTANEOUS CLOSE PARALLEL landing.
https://resources.globalair.com/dtpp/gl ... PRM28R.PDF
LDA should not be selected but current FG program choose LDA as a default landing method for KSFO-28R.
You can use ILS with manually tuning to 111.7.
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Re: 777 Autopilot Glitch

Postby Octal450 » Thu Aug 31, 2017 1:27 am

Rgr.

@Hyde hello
Have you seen my autopilot rewwrite. What are your thoughts?

Kind Regards,
Josh
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Re: 777 Autopilot Glitch

Postby Hyde » Thu Aug 31, 2017 3:03 am

I haven't had time yet. I will check.

Thanks,
Hyde
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Re: 777 Autopilot Glitch

Postby Octal450 » Thu Aug 31, 2017 11:01 am

Alright. Keep me posted.

Josh
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Re: 777 Autopilot Glitch

Postby Hyde » Sat Sep 02, 2017 8:35 am

I've tried your program.
I find some side effects such as, elevator manual trim does not work on ground, roll command does not work during take off until autopilot engage...
I haven't checked inside yet but I can't get it all.
Since your program is much stabler than mine so I will take one by one.
And I find the latest fg has some glitch on route manager. I have to fix that first.

And I notice new sound data is in, are they all legitimate?

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Re: 777 Autopilot Glitch

Postby Octal450 » Sat Sep 02, 2017 12:32 pm

Hi Hyde,
I don't know, I didn't do that.

Those seen to be caused by outdated logic, which I did not touch.

Where can I find your latest 777? Perhaps the FGMEMBERS is out if date. I can apply my changes to your version and fork and push to my personal github for you to check.

Kind Regards,
Josh
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Re: 777 Autopilot Glitch

Postby Hyde » Sat Sep 02, 2017 11:13 pm

Since github repo can be modified by many people without our permission I stand back from it.
Our repository is https://gitlab.com/fg777_seattle/fg777_seattle
Please make your change and submit the merge request.
Not big change. Please divide to small changes wherever possible.

Thanks,
Hyde
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