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ILS landing alignment


martinstebbing

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I have been puzzled for years why so many of my 3rd. party airports (not sure about FS9 native airports - I hardly ever use them these days) set my a/c, when it is supposedly 'aligned' with the localiser, so that it would land on the grass, or at least way off the runway centre line). Surely can't be a fault at so many of the airports I land at?! I used to correct the problem in AFCAD2 but it happens so often I have almost given up.

 

Screenshot shows just one example of an approach where the a/c 'thinks' it's properly aligned with the runway...

 

I have a magdec.bgl file from 01/01/2017, BTW.

 

ILS.jpg....

 

Any ideas on a 'global' fix? (??)

 

Thanks

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Martin - Just a second check of things, I use Skyvector to verify my ILS headings, altitudes and frequencies against MS published settings. I had one airport, that I never could get right, and when doing a check of frequencies and headings, I found that MS had published the wrong frequency. Have you tried default aircraft to see if they line up properly?

 

Good luck - Rick

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Thanks for the replies - yes, I have used the default c170 in the past to test things, and when adjusting AFCAD files to make airports I fly to frequently 'work'. But as I say, there are just so many I can't imagine that they are all due to mistakes in the airports' AFCAD files!

 

I now update the magdec file from time to time, as per advice on other forums. I first changed from the default file just in order to try to fix this very issue, so I don't think going back to that 2003 one is likely to help. Maybe you could explain your reasoning. Thanks.

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Only certain for the FS9 default ones (which I rarely use). As I said though, I originally updated the magdec file at the suggestion of folks on AVSIM (many moons ago) to correct these same issues when I was using the original file.

 

I can always try it out again, just to see, of course. I did back it up... I'll post back with any results, good or otherwise

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Hi Martin, Sorry to but in mate, do you fly using the Garmin GPS?

I use that for my approach, when I'm on finals I take it off GPS then switch to APR, I've found the GPS almost brings you in, I switch off the AP and hand fly it in.

 

I'll admit I'm not a great pilot but so far I've always been in line with the runway using this method.

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I have been puzzled for years why so many of my 3rd. party airports (not sure about FS9 native airports - I hardly ever use them these days) set my a/c, when it is supposedly 'aligned' with the localiser, so that it would land on the grass, or at least way off the runway centre line). Surely can't be a fault at so many of the airports I land at?! I used to correct the problem in AFCAD2 but it happens so often I have almost given up.

 

Screenshot shows just one example of an approach where the a/c 'thinks' it's properly aligned with the runway...

 

I have a magdec.bgl file from 01/01/2017, BTW.

 

[ATTACH=CONFIG]198428[/ATTACH]....

 

Any ideas on a 'global' fix? (??)

 

Thanks

 

Your PFD shows you significantly to left of the ILS and about 1/3 dot low. Some companies would require G/A at that point. You have about 6 kts of mostly crosswind moving the aircraft to the left. Can't see whether the AP is still engaged but I'd offer that your aircraft may be to blame here. Although the "ILS" button is not illuminated???

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I came back here to post a reply to say I was obviously confused yesterday. I see you noticed this before I did! Not sure how (or even if!) my brain was working. Although I have indeed had this issue at a number of airports, the screenshot here clearly shows that I am not properly aligned with the localiser. As I disengaged the Autopilot and landed on the centre line manually, the PFD no doubt lined up properly.

 

The A/P was engaged, yes: the ILS button you can see only shows an added G/S indicator on the PDF, it is not the functioning button which engages the autoland (or whatever you want to call it) - that was set and the a/c was descending fine, from a vertical point of view at least! (The glideslope is not an issue: the A/P corrects this fine by varying the V/S: the screenshot just captured a moment between corrections).

 

I have just tried putting various aircraft on the same runway centre line (WIMM) and tuning to the localiser frequency. They all (apart from, oddly, the default Cessna, which shows the needle slightly off-centred - how is that significant??) show the PDF needle dead centre.

 

I think you are right - the problem here must be aircraft related: the autopilot is not aligning the aircraft accurately with the localiser. The screenshot was taken using a PA A320 with the PSS A3xx panel. Most likely it is something with the PSS panel that is causing this (which I would not ditch for the world, having flown happily with it for years and years!). I haven't in the past thought about the issue being aircraft related, but although, as I say, there have been several instances where the problem has definitely come from the AFCAD, maybe mostly it has been the aircraft that has been the cause. I shall have to note in future whether it is always when I am flying with the PSS Airbus panel that the misalignment occurs.

 

I tried replacing the magdec file, BTW, but no change (as you would expect, if the problem is aircraft related).

 

I'll do some tests (I need to be on an approach, rather than just plonk my plane on the runway, so it'll take some time to get anything conclusive) and post back anything useful. Maybe I have not been setting up the autopilot correctly for landing with this panel for all these years?? (I do not usually choose a runway from the CDU arrivals page, I enter the frequency and course directly into the Radio Nav page: you have to do this anyway, even if you set a runway first, but I need to experiment a bit to see whether this makes any difference or not - I'll repeat the flight from which I posted the screenshot and see if I can do anything to correct the approach path).

 

Thanks,

 

Martin

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Martin - Good luck on finding a fix. I must admit, I am watching closely as I think I am learning something new just watching the conversations. Until yesterday, I never knew the meanings of AFCAD, ADE or MAGDEC terminologies. I guess, all these years, I have been just a "plug and play" flight simmer, with only a few tweeks to FS along the way! Anyway, keep your updates coming, I'm always wanting to learn more!

 

Rick

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The screenshot was taken using a PA A320 with the PSS A3xx panel.

 

Martin, I think that looks more like the Wilco Airbus panel than the PSS one. Whichever it is, maybe a Navdata update for the FMC would help?

Tim Wright "The older I get, the better I was..."

Xbox Series X, Asus Prime H510M-K, Intel Core i5-11400F 4.40GHz, 16Gb DDR4 3200, 2TB WD Black NVME SSD, 1TB Samsung SATA SSD

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Thanks Rick, I'll certainly post any useful discoveries!

 

No, it's definitely the PSS panel (but I have added a few gadgets, like the timer you can see). I did update the Navdata several months ago and it hasn't helped. Maybe I should subscribe to Navigraph and get monthly updates, but it is not that cheap (when I only work a few hours a week now - and spend a lot on FS9 - new airports, AES credits and so on - as it is!).

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Martin - Not a pleasant thing to go thru, I am sure! Just a quick question, the above panel pic, the screen that has the red circle on it, why does the GS say OFF?

 

And, you are using MS FS2004, with MS default aircraft, and third party airports? Have you tried that same approach using MS Kuwait airport?

 

Good luck, I hope someone comes along and has had a similar problem and can provide a suggestion for you!

 

Rick

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'GS Off' is just for the GS dots on the display - the Localizer is engaged with NAV (NAV/GPS selector at 'NAV') and the GS is engaged with 'APPR'...

 

Martin, don't feel bad! I just did a short-haul flight from Tehran to Kwait Intl. I was given an ILS approach to runway 33R. Even though the glideslope diamonds/arrows were showing, it never did shut off the altitude hold, so I was forced to kill the A/P and manually land.

Still thinking about a new flightsim only computer!  ✈️

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I know you're using 2004. However, just out of curiosity I shot the same approach to 33R on 110.5 using FSX.

 

The approach worked perfectly, EXCEPT, I was being lined up and on approach about 100 yds. to the right of the runway. In fact the GPS even showed the 33R appr lines being to the right of the runway.

 

Sounds to me like a basic alignment error in both FS9 and FSX.

Being an old chopper guy I usually fly low and slow.
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a basic alignment error

 

Hmmm... technically, what would that be though? If the ILS is set up correctly in the AFCAD (and for the most part if you plonk your a/c on the centre line and tune to that runway's ILS frequency, the needles align dead centre), why is it that some planes do not align themselves to this signal when you are on an ILS approach?

 

As you say, all works perfectly (though sometimes, yes, the plane just refuses to descend when it hits the GS - in some a/c, remember that you have to switch off the ALT HOLD and/or HDG HOLD for the LOC and/or APPR to work) except for the fact that you are descending towards the grass verge rather than the centre line, as the instruments and the view out of the cockpit window both show!

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I tried an ILS landing in the default C172 at the default Kuwait 33R with the latest Magdec.bgl installed, and the (steam gauge) needles were perfectly aligned.

I think this issue happens when a glass cockpit 2D panel is stretched to fit a widescreen monitor - the stretching is just enough to move the aircraft symbol either left or right of the magenta line.

If you try the same approach with the same panel at 4:3 ratio, I expect all will be well.

Tim Wright "The older I get, the better I was..."

Xbox Series X, Asus Prime H510M-K, Intel Core i5-11400F 4.40GHz, 16Gb DDR4 3200, 2TB WD Black NVME SSD, 1TB Samsung SATA SSD

NVidia RTX3060 Ti 8Gb, Logitech Flight Yoke System, CH Pro Pedals, Acer K272HL 27", Windows 11 Home x64

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I think this issue happens when a glass cockpit 2D panel is stretched to fit a widescreen monitor - the stretching is just enough to move the aircraft symbol either left or right of the magenta line. If you try the same approach with the same panel at 4:3 ratio, I expect all will be well.

 

Very interesting idea! I would say though that, whatever the instruments would show due to the monitor format, the a/c should land anyway on the runway centre, no?

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Very interesting idea! I would say though that, whatever the instruments would show due to the monitor format, the a/c should land anyway on the runway centre, no?

 

Indeed it should, if it is tuned to the correct ILS frequency and actually tracking the beam...

Most airports have an NDB somewhere on the field to one side of the runway, is it possible that the aircraft could also be accidentally or coincidentally tuned to that frequency and tracking that beam as well as the ILS glideslope?

Another (and more feasible!) factor is cross-wind - a few of the Airbus FDE's I've seen, including payware, have rudders which are too small to have any effect in cross-winds and need tweaking. You also need Autorudder on in the Aircraft/Realism settings when flying Airbuses.

Tim Wright "The older I get, the better I was..."

Xbox Series X, Asus Prime H510M-K, Intel Core i5-11400F 4.40GHz, 16Gb DDR4 3200, 2TB WD Black NVME SSD, 1TB Samsung SATA SSD

NVidia RTX3060 Ti 8Gb, Logitech Flight Yoke System, CH Pro Pedals, Acer K272HL 27", Windows 11 Home x64

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Martin - Out of curiosity, I flew the approach yesterday, FSX Boeing 737-800, RWY 33L, hdg of 332, approach altitude 2000' and the aircraft flew "dead nut" right on the center line!

 

This morning I flew the approach, Bombardier CRJ700, RWY 33R hdg of 333, approach altitude of 1800' and again the aircraft flew "dead nut" right on the center line!

 

I run FSX default, no scenery upgrades (I do love the greenery in your scenery of this area), 24" widescreen monitor, use default aircraft do not have any alignment problems. Sometimes, at the start to final, the aircraft might be pointing away from the center line, but if I trust the ILS settings, I let it run it's course, and it will be corrected by the time it gets to the threshold of the runway!

 

Good luck Martin! Something strange is going on within your software, settings or whatever and I wish you luck finding the solution! I would try changing that aspect ratio to see if that helps? Anything is worth a try!

 

Rick

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[ATTACH=CONFIG]198562[/ATTACH]Martin - Another observation? Instrument panel is showing ILS1 109.30 CRS 046 IDES? Are these the settings you have entered? If they are, I am showing correct settings should be:

 

RWY 33R 110.50 CRS 333

RWY 33L 109.50 CRS 332

 

Sorry, if I am quick to jump, it appears on the instrument, just figured, I would ask!

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ILS frequencies and headings may differ between different versions of the same airport: quite a few third party addons do not have quite the same values as FS9 defaults (or even alternative addons of the same airport). If the frequencies had been off, the a/c would not (presumably) have captured the localizer at all, but headed off in the wrong direction, rather than line up slightly to one side of the LOC beam.

 

I think I need to try the same approach with various aircraft to check whether it this is due to particular panels (and whether having widescreen panels or not makes a difference: I think I have one or two a/c where I have both panels installed and I can try with the standard 4:3 intsead of the 16:9 I always use).

 

If every plane I try has the same deviation off the ILS, widescreen or not, then that will be one important factor ruled out, and I can try other stuff.

 

Might take a few days for me to get anything meaningful but I will post back results, of course.

 

Thanks again for the input.

 

Martin

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