Can anyone tell me why anytime I activate APPR in IF, it starts to over-adjust by pointing the nose up dramatically then going back to the original position? It can sometimes also sway side to side too and it gets super annoying. Yes I watched the APPR tutorial from IF and idk what I’m doing wrong.
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You need to make sure your aircraft is properly trimmed.
In the trim box - you want no coloured bar. If the line is going down from the middle, you need more positive trim, and vice versa.
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In addition to what Benny said, I personally have a few tips from when I used to use APPR.
First, it helps to be lined up perfectly on the Localizer, and to have a vertical speed of 0, and be under the glideslope. What this does is stop the dramatic movements, and since you aren’t descending, it will smoothly catch and lock onto the glideslope when you reach it!
Secondly, if you are turning into the approach, I find it helpful to be doing a manual turn (and this takes some practice, so don’t get frustrated if you can’t do it right away) when I intercept the localizer. I keep my angle at 20 degrees, which is the max turn angle, so that when I engage APPR, it can’t roll anymore than it already is and you won’t experience this violent movements. Like above, I try to have a VS of 0 and to be under the GS
Hope this helps! If you’d like, and if I have time, I can try recording myself doing each of these and share them.
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Ok, thank you guys sm i appreciate these tips
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The above are good tips for dealing with your question. As far as why this happens: the sensitivity of the autopilot is increased when you activate approach mode, which means it will align with the runway much more accurately when you have a crosswind.
You may notice when you are in cruise, if you have a high crosswind the aircraft will stay slightly off course due to the sensitivity being lower when LNAV is engaged. This is not an issue in cruise, as airways are 4nm wide on each side. However, this is an issue on approach, because runways are 150ish feet wide, not 4nm. Therefore the sensitivity is increased during approach, so you will see the autopilot correct dramatically for it, and align you perfectly with the centerline.
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