Approach instability

Could you please help in this issue… I intercepted the localizer at 30 degrees where i activated the APPR, but unfortunately ended up in a mess as you will see in the video below… That ruind my beautiful approach… Was the intercept speed high so the aircraft was struggling to intercept the localizer? What the perfect speed should have been?

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Was the airport selected in your NAV1?

Sure it was tuned… The runway 19 of DTTA was tuned to NAV1

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No dear… The GS interception altitude for this runway is 2000 feet… Each airport has its individual glide slope interception altitude… For example you can’t intercept any runway in HUEN at 3000, you should be at 5000… The altitude was correct according to the approach selected and Jeppesen Charts…

Alright, then my mistake. I just know from radar training that we set most ILS approaches up at roughly 3000 ft AGL, and personally, when I fly, will set myself up at 3000 ft AGL (according to terrain) and continue that way, but it is up to you how you do things.

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Hello, I made a topic on this a couple months ago, do check it out for some more tips:

From what I found, I had increased the sensitivity of the sim all the way up, which therefore also caused the sensitivity of these intercepts to also be highly sensitive. In that case, it will make these aggressive swerves left and right to localize the path exactly, leaving no room for deviations or error. I advise you reset all controls to the default before starting your next flight

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It’s not up to me… When i selected the type of approach from approaches available in IF, the FAF was set to 2000 feet to be net by VNAV… Not all airports have the same altitudes thus not all of them has the same glide slope interception altitude… That’s basics of ILS aporoaches… Apparently the problem wasn’t related to GS, I believe it’s related to localizer interception which a speed issue

I normally wait until I’m fully on the ILS glideslope before enabling APPR mode, not at an angle. The aircraft does slightly move left to right for a few seconds to ensure I’m lined up perfectly with the runway.

I’m using a joystick… Does this related to this swerve? Does the speed play a role in this case?

I’m pretty certain that speed is not an issue in this case. Normal speeds for these are anywhere from 160-200.

I used to do that, but sometimes i get those swerves as well… I have been told to enable APPR on a 30 degree angle which would stabilise the aircraft better but unfortunately i got this result… Some approaches don’t have a distance enough to wait…

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Why I believe the speed could be the issue because i noticed that the aircraft has overshot the localizer points slightly and was trying to intercept them again aggressively in a right angle… I’m pretty certain the altitude was right because it was according to the charts and IF’s selected approach. Moreover when the aircraft has gained altitude while trying to align itself with the runway i ended up above the glide slope

I just did an approach and landing at DTTA rwy 19 in the 772.
Did a 30 degree intercept at 2000ft, 180 kias, flaps 15, and activated APPR just before PEMED.
37% load
20% positive trim

No issues at all

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@Andre_S So what do you think the problem was?? The wind was 100 at 8 knots… my flaps was 25? Could that be the issue? Trim was based on the disappearance of the pink line

I’m not sure. Looked like your nose was high during approach.
What was your load?
When did you activate APPR?

I gradually extended flaps. At 5 nm I set flaps 30 and put gear down. 150 kts.

@Andre_S I activated the approach while the aircraft was turning to enter the red cone. I had to be at 2000 feet but the aircraft increased the vertical speed while turning (don’t know why🤷‍♂️)… I didn’t do anything to change the pitch… VNAV was active to descend to the assigned FAF altitude… Load was 33%

Try to activate APPR farther out when established on a 30 degree angle. Use less flaps.

You should be at 2000 ft already at PEMED so no need to have VNAV active

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30 degree angle means final approach course minus 30?! And what about the speed? Sorry for many questions

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Final approach course plus or minus 30.

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Great so it depends on the direction of turning into final either right or left, doesn’t it?

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