Hi,
In a last generation simulator like MSFS, how are we supposed to land a plane correctly having this situation almost all the time in final?
When can we expect a fix? (screenshot at Stuttgart EDDS)
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Moved to #community-support:aviate-navigate-communicate
Also, if one does file Bug Reports, removing the Template makes the reproduction attempt more difficult or impossible. Do not remove the template.
Consideration
ILS is a 3-6 degree wide cone. VASI/PAPI is 10 degrees wide, and could encompass a vertical hazard thus resulting in a steeper angle. Thereâs at least two on the starboard side (aircraft heading relative) of the approach.
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Itâs not unusual IRL for the PAPI/VASI (collectively called VGSI) lights to not reflect the same approach as an ILS indicates. It will be noted on the approach chart. As an example, at KIAD, ILS runway 19L, youâd find the note: "VGSI and ILS glidepath not coincident. VGSI angle 3.0/TCH 75, with another note: âGS 3.00//TCH 55.â TCH is threshold crossing height. Basic geometry would tell you that using the same descent angle but crossing the threshold at different heights means you will arrive at different touchdown points. Thus, youâll get a different view of the VGSI lights depending on whether your ILS crossing height is above or below the visual crossing height.
So there is no error in those indications in all cases. Thatâs not to say that there may not be errors in some of the thousands of approaches in MSFS. The basic rule is: if youâre flying visually, use the lights to help guide you down. If youâre flying an ILS approach, fly the glideslope indicator to touchdown, even if you make a visual sighting of the runway early.
Regards
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737NG Driver did a video on this topic (heights not completely accurate at threshold).
Just to add to Habuâs reply, if your FMS shows a velocity vector/flight path marker, cross check it to see where your landing spot will be. The VV is very reliable - back when Visual Approaches werenât a thing yet in the Garmins, I flew it all the time as a final check that Iâm going to intersect at the TD zone.
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Generally for bigger aircraft and nearly all scenery this video is correct, at least for me. The glideslope is a little too high over the threshold point and most landings do go long on the diamond, at least in larger aircraft anyway. Having said that the video has 32,000 views, 1.4K thumbs up but not a bug report that I can find here? He says in the video he mentioned it to Asobo a while ago and they said they think itâs good.
I wonder if it wonât really get looked at as it is not reported a bit more formally as it just got lost on the pile? A sort of âNobody Goes There Anymore, Itâs Too Crowdedâ thing where everyone else thinks it is reported but being ignored, when itâs not actually been reported for a year or two?
Rather than being a general bug it could be scenery related. Plus once at minimums the glidescope is not the primary reference. Itâs quite a complicated one to generalize about I guess Iâm trying to say.
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I still donât understand why it has being moved and not considered as a bug.
The video says it all, airliner pilots see it as a bug.
It should be in this category to be voted, so Asobo will look into it hopefully.
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I think the bug template rule is pretty much mandatory, as without the steps etc it puts a lot of work on the people digesting the reports otherwise, and thereâs a lot of reports going on. With some new info in this topic it might be worth logging it again using the bug template?
Also, check how distinct it is to this one (it might be a separate bug-ette rather than exactly the same etc)
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You want template?
Give a brief description of the issue:
When locked into an ILS approach, the PAPI lights often do not match with the glide slope
Provide Screenshot(s)/video(s) of the issue encountered:
Detail steps to reproduce the issue encountered:
Fly an ILS approach at EDDS for example and compare to the PAPI lights
From the FAA AIM (section 2-1-2(b) Visual Glideslope Indicators):
PAPI angles are based on obstruction clearance +/- 10 degrees from the runway centerline, up to 4 miles from the threshold.
The ILS provides for obstruction clearance in a 3-6 degree angle on a 3 degree glide path.
Therefore, if there are obstructions in the PAPI clearance area (e.g. a tower off to the side of the rwy) that donât exist in the narrower ILS clearance area, the PAPI will have to be a steeper angle.
I checked the chart for EDDS ILS/LOC 25 in Navigraph; the ILS glidescope is listed as 3 degrees, and thereâs no warning that the PAPI lights are not coincident with the ILS (which there usually is if theyâre different â unless thatâs something only American charts list and European charts donât?).
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Could you please move it back to the bug section, as it is clearly a bug?
My last post contains the template
thank you very much
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I think the only variant on this bug worth any more chatting about is that if you completely take away the PAPI issue heâs also saying that the ILS glidescope puts you too high over the threshold as well, so itâs basically two separate bugs. It sort of gets into the weeds a bit as the issue then is that the RA shows 70 when it should be 50 feet, and then all sorts of details of if thatâs meant to be the bottom of the wheels or the cabin height. At that position it will mean things do go long for the 1000 zone usually. If you just fly 5 seaters it is probably never noticeable. Iâm not a SME in this, but I guess it could be a bug in itself and more repeatable reports would need to come. 737NG seems fairly convinced anyway, but thereâs no bug report for it as it stands I donât think.
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Itâs surprising that MSFS has had this issue with both GS and PAPI lights for a long time and it has never been addressed! The plane should be about 40-50 feet above the runway at the threshold and currently itâs about 100 feet or so above! I hope they fix this with the next generation (MSFS 2024).
There are issues in the configuration of airports in game, even if PAPI and ILS do not always match in real life and charts indicate that discrepancy too.
One of the most relevant recent cases I can remember is St. Gallen (LSZR), which is and official handcrafted airport. The latest charts I found for LSZR are dated on Jun 2022 and PAPI data are included in the airport information chart:
As you see charts clearly indicate that PAPI has 4Âș for runway 10 and 28. ILS10 is not standard in this airport and has a 4Âș glide slope too. However itÂŽs also true that the ILS10 approach chart also indicates that you should not undershoot PAPI below decision altitude due to obstacles (in particular thereÂŽs a warehouse very close to runway axis). To make things even worse PAPI is too close to runway threshold in this case (as in real life).
Anyway, following PAPI indications in game produces this result: you are at 30 ft when you did not even reach the runway threshold.
In game PAPI has an apparent elevation of around 2Âș when you follow 2 whites + 2 reds for this runway. And if you try to follow it that results in no proper obstacle clearing at all and places you always much below the ILS glide slope indicated by localizer. This 2Âș value is the half of both the ILS glide slope defined in the charts and also the half of the official PAPI elevation declared in the charts. ThereÂŽs an offset between both systems as PAPI is too close to threshold, but PAPI is still providing the half of the elevatation angle it should provide.
To calculate the appox PAPI elevation in game you can just use the radar altitude at a known point (the fences in the picture) and the distance from that point to the location where PAPI lights are placed (you can measure that in a satellite image using Google). This is just an estimation anywayâŠ
Something appears to be wrong in PAPI assets elevation setting in game as this affects many airports as other users have reported. If you set PAPI in game editor using the elevation defined in the airport charts you will never get a proper obstacle clearing on final. This is what I saw after testing the system with SDK when I placed PAPI lights in my addons at least. Either the elevation formula is wrong or the lights sequence changes are wrong, but thereÂŽs something there a bit not consistent I would say.
Cheers
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tâs not unusual IRL for the PAPI/VASI (collectively called VGSI) lights to not reflect the same approach as an ILS indicates.
It will be noted on the approach chart.
As an example, at KIAD, ILS runway 19L, youâd find the note: "VGSI and ILS glidepath not coincident.
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But this is not the issue here. The PAPI assets in game (the objects added in scenery editor) have several properties, like offsets, spacing and pitch (lights elevation). Pitch is whatâs used to set expected PAPI glide slope. If you set a typical standard value of 3° you will always crash into airport fences or nearby obstacles.
St. Gallen charts do not indicate difference in PAPI/ILS glide slopes only that obstacles are expected on final. Charts indeed set 4° glide slopes for both systems, however PAPI are giving you an effective 2° glide slope in game (at least that appears to be the case).
I have only used PAPI2 and PAPI4 in my addons but in both cases I had to set a much higher pitch than the official values for the airport. In the cases where there are evident mismatches in game the difference is clearly visible because PAPI either makes you nose dive into runway or sends you into nearby crops and house roofs. Something appears to be broken, despite possible discrepancies between ILS and PAPI that should still exist as mentioned by some of you.
Cheers
While this may not be the main issue here, it is important for anyone reading this post, to know that the Papi Glide-slope is not always the same as a ILS Glide-slope, and where to find that information.
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