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I have read the threads regarding the use of SCASM runways for placing lights over ground polys and such....

I used FSSC to make just the blank lights for 2 runways for my FSX 5B2 scenery, and it worked fine...

this time, I tried both FSSC and raw SCASM creation and I get slightly different results, BUT, BOTH give m this odd display (see image below)... I have seen this in the unfixed Just Flight's World Airports Vol3 runway lights for their FSX versions. (before the fix, but my charlotte still does it, so i uninstalled it, the rest they seemed to fix)

it gives very large odd effects for the light shapes and the fps hits the floor... (see the image)

I get it with either a runway made from FSSC compiled with scasm, or one I modified from one of the threads here at FSdeveloper for a scasm runway for FSX.

I included the image and my text file (i see the strobes needing StrobesN, i doubt that's why it doesnt work though, testing that now, just to see) for scasm compilation below...

anyone seen this issue, or know why its happening?????...

oddly enough, using FSSC, rwy 01/19 viewed odd, and runway 12/30 viewed fine when compiled from the attached raw... so, i wonder whats wrong with my 01/19 that is working just fine with the 12/30 compiled in the same file...?

it seem that even with -1 set for runway its showing a runway surface anyways.... could this be a clue to its error?

Ill include the FSSC raw text as well...


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Haven't seen those weird light effects before. But a performance slowdown is something I have seen before. Although with the latest sp that should be fixed.
That is what happened when I tried SCASM lights. Only mine were round blobs.. I'm guessing it is because we are using different light effect textures.
I have just tried everything under the sun....

can make 4 other runways, not as many problems, but when i make one for the rwy 01, BAM, the funky lights...

I have NO idea whats doing it... ive tried 90 things... all the similar results...

reinstalling sim...

this light issue with the World Airports 3 lights (before most of their updates) and this now with JUST this runway 01 on mine, shows on BOTH my laptop fsx and my main sim machine fsx...

im wondering if its in some addon i have put in both sim...

i doubt it... but i gotta see...

I have FSXA, so its sp2....

Im stumped...

I didnt have a scasm runway issue until this scenery build and im doing it with sbuilderx and arnos ground poly wizzard, so im trying to do it right...

Ill report back when the sim is clean and fresh... i am positive it will still do it (my money is on a conflict within the ILS imbedded in the rwy01 from default, but its a guess, as i have litterally tried everything i can think of, and it just doesnt make sense.)

:(.... have some spam... :spam:
The runway I was having the same issuse as you was runway 01/19. (KSGU) Could it be possible that runway heading is what causes this?
No dice... Same thing

runway 12/30 displays just fine.... Runway 01/19 still displays funky...

I am stumped, and out of ideas...

with default scenery, it still does the same thing... even finding the apx*.bgl the airport default was in, removing it, and ONLY putting in the scasm runway, and it still showed the same funky deal... (so my theory of it getting whacked from a default item is out the window... im happy, didnt want to find a workaround for a default conflict, but still no answer)

So... the airport is KGFL. FSX Accelleration... I included both working and not working runway raws below.

Can someone take a gander and see if it does the same thing in your sim??? or even see what i may be doing wrong...

Thanks in advance...

File 01 is Rwy 01/19 and the bad one, file 02 is rwy 12/30 and works fine... Both were output from FSSC, same results either FSSC or manual scasm compile... They look identical, but.... I am out of ideas


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UtahJazzfan said:
Could it be possible that runway heading is what causes this?

I thought about this, but I also got 'some' odds with some tester runways when I made 6 runways, different headings... some showed odd, and the one pointing sort of north showed ok, so I couldnt decide WHY some did and some didnt...
Well, after several hours of testing, changing, etc, it seems its an fsx issue...

World Airports 3 scenery I have that does it in 4 of the airports, seems to have a complete workaround to fix the issue... I see in the scenery folder of the updates, they scrap the scasm runways and go for a custom coded, built vasi/papi objects, runway lights bgl file thats 300k, and such, so obviously, there is no more 2k scasm generated runway lights *.bgl

this tells me that they, too, tried and failed to fix this issue with scasm technology of old, and moved onward...

I cannot create my own papi light objects, and runway light objects, so... after trying a handful of workarounds, to no satisfactory avail, I am forced to use default runway textures (YUK) and build on top of that.

1 - I tried to make 3D runway lights, which would have been cool, but NO way to get ANY effect (and I knew this, but had to try and see how bad it was) to show past 1 mile....
FAIL - Distance
2 - I tried to get the runway to at LEAST use the MALSR from underneath (I dont want to code a rabbit) and PAPI from the default (PAPI was the only thing that DID work like I wanted it to), and make runway lights, but FSX wont let you make those without edge lights that show on the edge and disappear according to viewing angle... Using SbuilderX for ground sat coverage, means i dont have to make holes in it to show MALSR and PAPI....
FAIL - MALSR wont show alone without edge lights
3 - Tried to make smaller runway underneath to get MALSR, but again, wont work without edgelights, made it 15m wide (so lights wouldnt peek out from edge on wider viewing angles, such as downwind pattern flying, etc), but HAD to make it at least 300 m long or else it would show unpredictably along MALSR lighting... ADE and thus FSX 'lets' you make one as small as 3.4m long, but will inevitably make it about 300 to 400m long ANYWAYS (im sure so it can put that STUPID looking tire-smudge build in the runway), so best to make it that long so you can control WHERE it shows....
FAIL - lights peek out from under runway when viewed from the other end... making an unsightly light blob when approaching the runway from the opposite end of the MALSR display... also, do I really need 9 runways overlapping to put lights on 1 addon airport runway???


4 - Trying to use the default runway and place all layers of runway character on top of the default so I can use the default lighting...
FAIL (I feel) - My top layers obscure end lighting... I need to play with HOW transparent I can make the markings to get the lights to show through... I ran out of time last night and needed sleep... I am burning up my whole weekend just to figure out I cant do ANYTHING I wanted with this lighting (especially things that worked in the past, and have no apparent logic as to why they wouldnt work now, and so you structured the build earlier in the process to account for this working now)... PLUS I have to rework the 'way' I am doing my markings, now that I cannot use my base runway.... Not the END of the project, but it sure throws a spoke into the wheel, because being forced to use the default runway, it takes away from the 'look' I was trying to get into this field... its now going to look like cheesy default crap unless I can get the overlays to knock it around enough to NOT look default and STILL show the edge lights correctly.... ARRGH

Yes, it fixes the lights, but takes away my runway work I did... The runway is not going to look anywhere as nice...

:confused: Frustrating for sure... (have some spam... :spam: )
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I have this same issue, now and then!

I've also encountered this same issue here and there with custom airports, and it's very frustrating, especially after a long flight when you have a glimpse of the airport lights and start the slide show and eventually a CTD on final!

I can't see why it should be a fault with my FSXA install, since this is happening in a few places that possibly use the cursed scasm method, while elsewhere there are no troubles at all, even with a very complex scenery.

In some instances I was able to eliminate the solid light issue just disabling the scasm light placer bgl from the scenery, loading the AFCAD in ADE and using default runway and PAPI lights.
But this method sometime isn't working and messes up with the overall ground textures.

When this kind of lighting appears, as you report I always get a huge frames' drop, but I always thought these kind of lights might be just an effect and not a cause, but I also noticed that when I was able to eliminate them I had no more problem using the airport...

I would be very much interested in hearing an in depth analysis and for a possible solution too!
Yes, it does drop the fps to its knees... the rabbit also wont work on any approach lights.

I did get a similar look with an effect I tried to use a custom halo on with blend set to 2 in the *.fx file... i checked and it was nothing the default halo didnt have in it, including the alpha, so the 'over blending' might be a result of something happening in the sim and not the particular effect used...

i think its something odd happening in the sim... I am done with trying to fix it, as it my be something the scasm runways are triggering 'some' of the time... and not others...

I suspect thats why the guys that do the World Airports series went another direction with the runway lights... (they sure know alot more than I do, and THEY abandoned scasm runway lights)

I already tried hours worth of this and that (little changes, process changes, etc), and I saw NO discernible pattern... so I suspect its a sim anomaly or sometimes works, sometimes dont handeling of scasm coded bgls... I could be completely wrong (have been several times in the past, so why should NOW be different(grin))

I won't chase this anymore... Im already working on trying to get the default runways to work with my custom overlays...
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=> solved <=

Ed, it seems I've found the solution and I was able to fix a few airports and it worked faultlessly! And it was pointed at in here already!
By fixing the runway heading in the disassembled SCA either subtracting 180 when it's above 179 or adding 1 or 2 deg, I have perfect FPS and no more solid bulb lights in one stroke!
Why so and only for some airports? I can't say, but it works indeed.


You, Sir, are a genius!!! And are my favorite person right now...

I NEVER thought of trying that... it works!!!!!!

I just oriented the runway to be one of UNDER 180 degrees, and its working...

where before, everything was oriented for 01/19 at 358.44* (and it never worked), and the working runway was placed at 110.xx* (and 12/30 did show correctly), as soon as I compiled 01/19 upside-down, and made it rwy 19 instead of 01, and placed it at 178.44*, I didnt need to add .02 degrees to it as someone suggested... it seems to be working

WOW, thats got to be it... 0-180(or, maybe 0-179.99)* is all it wants, NOT the 'other side' of the runway asmuth.

You Sir, ROCK!!!! When I searched for this issue before, I never found that thread you posted.. I am so glad you found it and figured that one out...

MOST excellent...

This needs a wiki for scasm runways, and this is PIVOTAL information THANK YOU!!!! When I get 5 min to think, maybe Ill compile the information we know about scasm runway creation and make a wiki on here...

THANK YOU THANK YOU THANK YOU.... I owe you lunch!!!! :spam:

You make me blush!:eek:
After all it's not my discovery, but it's just an information I pass on... And I'm with you: a pivotal and wonderful discovery! I'm also enthusiast about this solution.

I agree it should be put in the Wiki and detailed for all who encounter this very frustrating trouble, and to rescue airports that may be not that bad in FSXA and that otherwise would become a huge obstacle to use.
From what I gather, the higher value should stay below 179 deg (that is actually 180, counting from 0, i'n'it?) and adding 1 or 2 degree would be required whenever this issue is happening on runways that already have an heading value below that and still show up in the slide show with the horrendous blobs: I checked this with a runway set at 74.xx and 125.xx and indeed it worked there too.

Well, I definitely appreciate your input, as I was completely lost...

Thank You again...

I think now, I can even delete the bad runway lights on the World Airports 3 KCLT (which they never patched or fixed, and I just uninstalled that airport due to the bad lights...) They have the lights in a runways.bgl that can be removed or better yet, i can decompile, change some values, and recompile and see if it jives... if not, ill just see if making a new one works using the runway coordinates so i dont have to position fiddle too much..

Excellent, thanks again...
You're welcome ;)

Just to be clear, I now understand the 1 or 2 degrees should be added whenever the runway has an integer value (say 90.00 should be corrected to 90.01!).

As stated in the linked thread

Runway heading must be declared in the range 0 to 179
No integer values allowed!!!​

I would also think that it would be rare (not impossible) that a runway heading be 'exactly' an whole interger value such as 90.00 or 112.00 degrees... when we research runway data on sites such as airnav.com, we find often that runways headings are always down to a whole degree value and usually NOT a precise value... i forget where it was (other than the sim itself) that showed decimal heading information... so, yes, we would need to make it more precise when WE enter it in a scenery build. If the sim takes it down to the 100th of a degree, then adding SOME information to that precision, even if its to NOT get the odd lights, well, that should be standard build practice.

but that is a good observation as well.... Thanks