When turning from GPS to Nav 1 and turning on APPR even after lining straight on the runway in approach, my plane moves right left a lot to align again even though it may just need a small allignment which doesn’t look realistic at all. Any solution for this?
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If you are established on final when you switch, then it will pretty much do this every time. Unfortunately, it is a shortcoming of the autopilot in IF.
I have found that if you switch from GPS to NAV while turning onto final, then it will not turn drastically since the airplane is already in a turn. Instead, it will roll out nicely onto final without having to over correct like crazy. This is what I found works the best to avoid this issue.
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This is what I do too when having an ILS approach!
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Yeah sure will try
I’ve also encountered this issue frequently. You will also notice that the aircraft has a tendency to pitch up while capturing the glideslope. As @SuperJet115 correctly pointed out, this is just how IF’s Autopilot is implemented. The lateral error signal is minimal when the aircraft is already aligned with the final approach course. The aggressive initial gain is probably scheduled so that off-course ILS captures can be done successfully.
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I found the best solution is to turn off the AP completely after making sure to be properly trimmed and hand fly the approach manually all the way down from the base turn. Unless in low visibility of course. :)
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Is it better to keep the sensitivity low while manually landing because my airplane moves a lot and it’s difficult for me to align on the runway. I have stopped landing manually and always land by APPR because of this issue.
I use medium sensitivity.
I practiced a lot with the medium sensitivity but the planes nose keeps moving up and down or left and right 😑
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In the official tutorial the instructions are to intercept the GS from below while at level altitude. Following those instructions should avoid pitch-up.
ILS is a precision approach. When switching from alignment guided by the alternative non-precision navigation methods, the difference of up to a few degrees of heading error intrinsic to the non-precision modes (GPS up to maybe a degree and a half) can result in a significant lateral deviation.
The autopilot has to correct for that.
I think you misread what I wrote there and what OP may have experienced regarding the final approach course: You can be dead center on the LOC but as soon as you press the APPR button, the autopilot will turn left or right trying to make some phantom corrections. This is not whether you are on precision approach or non-precision approach. You can fly a precision approach without using the APPR mode, you know.
As for the pitch up trying to capture the G/S, this happens in the few airplanes I have tried on IF: 738, 77W, E175. I come in below GS and as that CDI gets closer, the airplane will pitch up as if trying to catch the G/S and then, descend. This motion trying to catch the G/S above you is not supposed to happen.
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Ok so I was trying to reproduce this with the 77W on approach to SFO 28R and it was actually very smooth going from approaching on GPS to hitting APPR.
Can you give an example which approach and aircraft you can reproduce this issue, and the setup for the approach?
So, I was testing this with the same aircraft and approach, once a straight in approach and once at a 30 degree intercept more or less. I was at 220kts during the intercept.
No pitch up whatsoever in intercepting the GS.
Again, can you give an example where I can repeat what you are reporting?