A220 LNAV Issues

Before I just go blasting defect requests I thought I’d ask - has anyone else had any issues with the A220 autopilot [LNAV] not following a flight plan?
I’ve had issues with mine a number of times now just looping around an active leg but not locking onto it. I’ve held its hand and walked it back on track, only to find after a few minutes that it’s wandered off again on me.
Anyone else experienced similar, or does mine just have ADHD (kinda like me lols) 🤣🤣🤣

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Has this happened after a tight turn on your flightplan?

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i think your waypoints might be too close together

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Initially yes, but no tighter than with any other a/c - I’ve only found the A220 to have any issues with it, A320, 330, 350, 380, B717, 737, 777, 787, Dash-8s, I’ve never had issues doing the same thing.
Also, I brought it back on track this morning with a fairly gentle angle, switching LNAV on as I closed to within a few miles of track and found that it just decided to do it’s own thing and not come back on track, was meant to be heading almost due west and instead was tracking south east.
Was doing a flight to Rome last week from I think it was Zurich utilising an SID, had a turn which was <80 deg, didn’t think much of it, came back to find it just looping around this turn (wasn’t a particularly short space between the turn and the next waypoint).
In any case, thanks for your thoughts, I’ll try space things out a little more and see if that makes a difference, was just curious to see if anyone else had similar experiences.

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I read it can happen when the waypoints are too close to each other. If you’re departing, hand fly the initial leg (with altitude and v/s on) until you’re away from the tighter turns.

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Yeh thank you mate.
I was just really curious, because I’ve only experienced it on the one aircraft type, so it seemed a bit funky.
But I’ll keep them more spaced out and see how I go in the future :)

Thanks mate!

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As a general rule of thumb I always delete waypoints that have a distance between it and the previous one of less than 10nm (if there is a sharp turn involved).

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Sound advice. What do you count as a sharp turn? Greater than 90 Degrees?

Usually anything over 45’.

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Perfect - thank you mate, appreciate your quick response.
Hope you’ve had a great weekend

If we had flight plan turning curves (as is a thing IRL) this wouldn’t be an issue lol…

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It’s interesting you found the ability to track waypoints may vary with aircraft.

I agree with other comments here, that waypoints too close together for the tightness of turn angle, is the likely cause of “waypoint sequence misfire.”

But it does make sense that the turn response of the aircraft being used could have a bearing on this.

Whatever might cause an aircraft to turn less degrees per minute, immediately decreases the odds you will make the next turn.

So there is some tighness of waypoint turn, where one aircraft will make it but another won’t.

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That’s a great point - I feel like the A220 does have shallower bank angles/responses than the other a/c I’ve used.

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I haven’t tested it, but it’s possible roll rate into the turn, depth of bank in the turn, and yaw rate once in the turn, could each be considered.

In actual flight, I might take extra caution to monitor the proper sequencing of turns when they appear suspiciously tight, and be ready to manually override the sequence when I observe it doesn’t work as expected.

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I think we need an update into IF LNAV system. Too much corrections and late turn, even opposite direction pre-turn. Especially on CRJs and Xcub

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