A strange LNAV glitch I had encountered

Sometimes when I activate LNAV a few minutes later after take-off, the autopilot starts to make the plane go left and right erratically, something like the motion of Dutch Rolling. Had to close the game and restart it only to have this not happen again. Anyone know why this is happening?

I’ve noticed this too when the plane is particularly heavy as well as if you’re flying at a low speed. Unfortunately, there is nothing you could do about this as this is hardcoded into the autopilot system, meaning that you’re going to have to try to gain some speed before engaging LNAV. It usually stabilises itself again once at a higher speed.

Before ending this, would you mind sharing the aircraft type as well as your load at the time when this happened?

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A359, 100% fuel load with N/A passengers and cargo. For context, it was an attempt to fly around the arctic and for how the plane could fly the longest duration.

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I have experienced this as well. I just tend to hand-fly the first 5 minutes of the flight and I do not encounter any issues with that. I actually find it pretty fun to hand fly it then. I see that your plane was probably extremely heavy because of the fuel load. For me, it only happens on rare occasion, though.

Yep, it does that to me too, but does the vertical speed always freak out when you engage AP after takeoff like mine does with every plane?

That is 100% linked to the weight of the aircraft, usually older generation aircraft (anything older than the 777-200ER) tend to have to problem when heavy loaded and climbing too fast too early! When I began flying in Infinite Flight my flights would always end up in a crash.