Hello folks, so today when I flew Lufthansa A321 from Helsinki to Munich, after I took off from Helsinki, it started rocking left and right, and it cannot stay stable. I don’t know if it’s something about the weight or what any other issue that may be caused. But this issue caused me not wanting to fly this A321. I have tested it with 50% load and it did the same thing as I took off. It was rocking right and left during cruise too. Also before the 24.4 update, when flying A321, it would never have that issue after I tookoff. For example, when I done a flight from CLT-MIA on the AA A321, it would never rock left and right after I took off. It stayed stable throughout the flight. Therefore, I would like to know what’s going on with this aircraft. Thanks.
Even if the issue discussed in that topic is similar, it is not the same.
The issue discussed there is about the aircraft losing stability at high altitudes and modifying its behaviour with a change in flap settings.
Here @Udeme_Ekpo brought up another issue, which is this
I did a bit of research and the issue seems to be something along the lines of the AP failing to capture a heading or a track (just because of the aircraft design) combined with a bit high AoA. I could be wrong here though so take this with a little grain of salt.
The A321 is old and that’s why it’s having issues. Here’s the feature request for its rework.
Okay? I’ve flown this A321 since 2015 and before that 24.4 release, it would never act like that after takeoff. But oh well, I will never fly that A321 until it gets reworked
I was able to reproduce the issue. It’s the autopilot failing to capture a heading or track.
The rocking is just a bit subtle, and it won’t make you crash. The issues I’ve referred to before would make the aircraft lose control and go in a dive after some time.
This seems to be kind of a new issue, most likely caused by the new update as we haven’t seen it before as far as I know. Unfortunately there’s nothing we can do before the devs fix it.
I’ve recreated this in casual server. The aircraft begins swaying as soon as you put your heading on.
The swaying is also noticeable while flying without AP. Turning is more difficult.
There has been a topic written before it, they’ve noted the issues internally.
The A321 is normally really sensitive to weight and speed and the rate of your Assent I would personally say don’t climb over 36,000 when over 50% of fuel personally stay between 330 and 340 at 290kts (M.78) and to stop the stall on departure set speed at least 230 to keep stable.
I’m going to be straight honest and say that it’s a physics issue. Retracting flaps 1 would cause the airplane to have an abnormally high angle of attack, causing swaying at typical cruising altitudes. This could easily be countered by flying lower (even though you shouldn’t have to), but that’s not the case anymore when I was testing (sways regardless now). The physics somehow worsened after the update. It’s about time for a rework if you ask me. If you still want to fly the aircraft, all I suggest is that you maintain an AoA of 1-3 degrees and n1 of around the high 70s to low 80s if possible. There’s nothing else that can be done right now.
After giving it a second thought, you may be right about this one. I decided to look at this at this again and I noticed a lot of corrections to the heading on the compass at stable altitudes and speeds. It’s still a bit strange as to why this would happen specifically to the a321 though. Autopilot usually never has been a problem, so I thought about other factors that would possibly play a role in autopilot handling, like physics for example.