I been noticing this issue on the a321 mainly as i fly it alot.
When I’m establishing myself on the ILS… Even though I’d be spot on, on the localizer and glideslope, the airplane takes a sudden right or left turn and pitches up like 10 to 15 degrees.
Any suggestions on how I can improve or what I’m doing wrong ??
What airport is this happening at, and what is the weather like? Sometimes it will make a seemingly large turn, but it will automatically fix itself. It has happened to me a few times before. You just have to let it do its thing and trust that it won’t crash itself.
You don’t have to be that precise for when to turn on with glideslope decending to the line. But there are some strong guidelines about localizer approach angle and glideslope intercept condition. You should be correctly set up on those before you hit appr. This is the official info below. Also @pog_3r if you’re having inconsistent results, this is good to watch.
Also I watched the video demo in @AviationFlyer 's support link. It looked to me like the localizer intercept angle was way too big.
Hey, thanks for watching the video! Can you please elaborate on what you meant by a very big localizer intercept angle? I was coming in for standard 30 degree intercept (approximately), though I’m not sure if that’s what you are talking about.
Yeah it might be we’re talking about something different, I’m not sure. I could only see the example youtube video in the support topic; the flight file didn’t seem to be available. This is the point in time I think when appr was engaged, and it looked like about an 80 degree angle or so, I thought?:
APPR is practically useless for me on landing as when you use it for Final Approach it will stay in the red box, which is good, but when u land then your nose will aim down and you will bounce off the runway so I just use APPR for Final approach but when I am close to the runway, I just turn of AP, flare and land.
A video of your approach would help clarify the details of what happened. Were you stabilized on approach, far enough from the runway before engaging appr? Also, I’d recommend watching the tutorial above, and use the setup (preparing for the approach conditions) mentioned.
it happened to me from Geneva to Bogota, it started doing S turns, I had to turn off the APPR and do a manual landing, it wasn’t that bad, anyway, it happened again and what I did was turning the APPR off and turning it on again, it helped.
Ah, I see where the confusion is. What I’m doing in that is engaging APPR while I’m still making the turn to 50 degrees, which in theory is meant to keep turning to 50 degrees until it intercepts the localizer which works most of the time but can also be quite janky.
This talks about how it can be quite janky if you don’t engage it when you’re on the intercept heading: Autopilot | Infinite Flight. Though it also talks about how you can still adjust your heading until it intercepts. This is one of those very abnormal corner cases. It’s weird because I’m turning towards that recommended intercept heading, which is the sweet spot for APPR, but it should only be capturing when getting relatively close to that. Here though, it doesn’t even capture but instead makes 360s.
The interesting part it though, I believe IRL, pilots can engage the localizer while making the turn so I don’t really consider it to be something that should be abnormal.
Though in practice, with these types of corner cases, it will just continue way past the heading even though as you see on the APPR button, it’s still flashing orange meaning it hasn’t captured but it’s APPR that’s having this effect on the bug.
That’s why nowadays I wait until reaching the intercept heading (approximately) before engaging APPR, but this can be problematic with late intercepts or continuous turns to final (these are rare and don’t happen much, but they still do happen) that can cause you to overshoot since by engaging during the turn, there’s a much lower chance of overshooting if the intercept is a little late.
My point is, this is definitely unintended behavior, even beyond it normally being a little janky/abnormal imo.