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Boeing 777 Autopilot

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Boeing 777 Autopilot

Postby turkish_aviator » Sat Apr 10, 2021 9:31 pm

I have the latest version of the sim, and downloaded the 777 from the "select aircraft --> browse" menu in the simulator. When i set a route from route manager and activate the LNAV mode, after a while of flying, the autopilot selects a waypoint from beginning of my flight plan and tries to turn back. I set the next waypoing that i supposed to go by "jump to" button in route manager, but when i reach the waypoint that i selected, it does the same thing again. How can i fix that problem? I usually fly with 4x time speed (i don't know did i said correct), can this cause that problem?
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Re: Boeing 777 Autopilot

Postby wkitty42 » Sat Apr 17, 2021 4:52 pm

you said it properly...

what happens when you choose the next way point after the one you are having a problem with? does the craft fly to it and then continue on or does it still turn back?
"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: Boeing 777 Autopilot

Postby turkish_aviator » Sat Apr 17, 2021 5:09 pm

Let's assume i have 8 waypoints, A B C D E F G H. When i reach D, the aircraft selects "B" as next waypoint, i click "next waypoint" to make it go to E, but when i reach E, this time aircraft selects C as next waypoint.
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Re: Boeing 777 Autopilot

Postby Isaak » Sun Apr 18, 2021 1:03 pm

There's a glitch in the Route Manager (RM) code. Using sim speed up (e.g. as you're doing 4x) increases the chance that the aircraft misses a waypoint because it can't correct fast enough. Then it will deviate from the flight path later on. When this bug occurs, you can fix this (for this flight) by deleting some waypoints. E.G. in your example: in the RM select waypoint E, click 'jump to'. Then delete 3 waypoints before the current leg, e.g. delete waypoints A, B and C. This moves waypoint F up 3 places in the Route Manager queue and thus makes sure the aircraft selects F after it reaches E.

I know this is ugly and requires your attention throughout the flight (but as responsible pilots we're always in the cockpit, aren't we? :p), but solving this bug requires coding skills that go way beyond my capabilities and I assume there's something off in the RM code itself.

You can prevent this bug from occuring most of the time (but not always) by:
- not using sim speed up,
- removing waypoints from your route that are closer than about 10 Nm apart, especially if a heading change of more than a few degrees occurs at the entry point of that leg,
- never using the same point twice (e.g. when you load a route and then select a SID, make sure the SID exit point is not duplicated (same for a STAR entry point).

I hope these hints make your flights a bit more convenient.
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Re: Boeing 777 Autopilot

Postby wkitty42 » Sun Apr 18, 2021 11:45 pm

turkish_aviator wrote in Sat Apr 17, 2021 5:09 pm:Let's assume i have 8 waypoints, A B C D E F G H. When i reach D, the aircraft selects "B" as next waypoint, i click "next waypoint" to make it go to E, but when i reach E, this time aircraft selects C as next waypoint.

what happens when you click 'F' instead of 'E'... does it select 'D' as the next after reaching 'F'?
"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: Boeing 777 Autopilot

Postby wkitty42 » Sun Apr 18, 2021 11:49 pm

Isaak wrote in Sun Apr 18, 2021 1:03 pm:You can prevent this bug from occuring most of the time (but not always) by:
- not using sim speed up,

agree with this 100000000%... the system has to calculate so many variables and when using sim speed up, there's a lot that just isn't calculated properly because of the large movements between each frame calculation... if the system works properly at 1x speed, there is nothing wrong... sim speed up is quite an ugly hack anyway and really should not be used at all... not for a proper and true simulation of a flight...
"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: Boeing 777 Autopilot

Postby turkish_aviator » Mon Apr 19, 2021 2:31 pm

By the way i downloaded an older Version of 777 from github and i didn't have the problem that i told even in sim speed up. Yes you are right, and i don't use sim speed up in flights that taking less than 6 hours. But after that my computer overheats and that's why for longer flights like Seoul to SFO i use the sim speed up.
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Re: Boeing 777 Autopilot

Postby V12 » Mon Apr 19, 2021 7:09 pm

You should find reason of that overhetaing before You damage some components. Larger fan, better heatsink, dedust all in the case.
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Re: Boeing 777 Autopilot

Postby wkitty42 » Tue Apr 20, 2021 5:36 pm

definitely find and fix the overheating problem...

if you have a laptop, be sure the vents are clear and that you are not using it on a soft surface like a bed with thick comforter like one of my clients used to do...

if it is a desktop unit, shut it down, open it, and vacuum out all the dust and dirt... pay attention to the cooler and clean it, too... generally speaking, you do not need to remove the cooler from the CPU to clean it... in many cases, you can remove clips or screws that hold the fan in place so you can remove it and get to the mat of dust and debris under it that is blocking the air from being blown into the cooler's fins... older systems generally pull air through the fins and blow out the top... in those cases, the mat of dust and debris will be on the sides of the cooler...

also pay attention to the case and the power supply... some of the power supply fans are pretty inexpensive and they will stop turning... when they stop, they are no longer pulling the heat out of the system... they are easy enough to replace, too...

in any case, definitely find and correct the cooling problem... you could end up losing your system from overheating causing damage to components...
"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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