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Introducing AFLT General Release

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Resource contributor
At long last, I am pleased to announce a substantially improved version of the Airfield Lighting Toolbox (AFLT) - Release 4.3.00. This new release enables you to add custom 3D lighting to your airports with only a few clicks of the mouse. While a few deficiencies remain, this release is still VERY useable and a VERY substantial improvement over its predecessor.

The most significant improvement is that taxiway outlines now computed by AFLT faithfully reflect the outlines in FlightSim. Thus, lights placed along the edges of taxiway curves in AFLT at an offset of, say, 5 feet will appear very close to 5 feet off the edge in FlightSim also. As well, as at real-world airports, lights on opposite side of taxiways now appear directly across from each other. This new release also contains numerous less-apparent improvements and a host of fixes.

At time of release, the only known deficiencies are:
  • AFLT doesn't handle well some instances of very short intersecting taxiway links of varying widths; lights on such taxiway links must be added manually; this will not be a problem at most airports;
  • Taxiway lights are occasionally duplicated or too many are placed in a short section of taxiway
  • Aero-navigational beacons do not illuminate P3D
  • Shadows of runway end lights and similar arrays appear at the center of the array rather than with the 3D model,
I will continue to work to overcome these deficiencies. In the meantime, AFLT will create quite acceptable custom lighting for most airports. And, if you encounter one or more of the above noted taxiway deficiencies, manual adjustment is quick and easy.

Please give it a try.

A BIG thank you to Tom Gibson who spent countless hours testing AFLT4 - allowing me to focus on development and fixes. Without his help, this version of AFLT4 wouldn't yet exist.

Finally, this new release is the result of several months of intensive development. While Tom and I have tested every aspect, it would be foolhardy to expect there are no remaining issues. So, you will be well-advised to backup your Project Folders (see the user manual) if you make significant additions to the stock data.

Many thanks, Don! Looking forward to give it a ride.

From mobile hence short
I have just discovered that the current release of AFLT 4.3.02. generates overlapping taxiway lights at the end of each segment. That is not supposed to occur and will be fixed in the next release. (This issue was discovered during development and fixed. Unfortunately, it seems I've re-introduced it in the late stages of development. )
I have just posted Release 4.3.03 to http://stuff4fs.com. It includes three major new features/fixes, namely:
  • overlapping taxiway lights at the ends of each taxiway segment have been eliminated
  • a bug that prevented compilation with new installations of AFLT has been fixed, and
  • obstruction lights and aeronavigational beacons are now fully operational;
and a number of other less-noteworthy ones.

However, AFLT is not yet perfect. I recently discovered that strobe seed values other than "0" do not display satisfactorily. For the moment, they are all treated as 0; hence all your "running rabbits" will be synchronized. Due to the seriuosness of the "no-compile' issue, I felt an early release was preferable to waiting until I developed a fix for the strobes (which are still quite useable). Also, I am still not happy with the spacing of lights in corners which, in certain circumstances, bunch up.

I will continue to work on these and other improvements.

I have just posted Release 4.3.05 to http://stuff4fs.com. It resolves most of the outstanding issues in its predecessors. As has been the case for a while now, Tom Gibson has devoted a great deal of effort to testing this release. Thanks, Tom (Let me tell you. he's fussy.;) If it doesn't work, he won't let it go!)

One user has reported difficulty in upgrading to 4.3.04 from a very early version of AFLT4 (4.1.16). If you are currently using a version of AFLT4 prior to the 4.3 series, your old data is probably not going to be of much value anyway other than recording the changes you've made from the stock data. So, you're probably better off starting from scratch with 4.3.05 (i.e., put it in a new folder). In most cases, you'll be able to recover with only a few mouse clicks.

P3D users get a bonus with this release. The LOD-variable lights can be made visible to over 15 miles. (Effects are cut off by the sim at about 7 miles.)

I expect to make at least one more release with new features. I'm still not happy with the way very short taxiway segments are handled. As well, I want to see if I can adapt the (extended-range) LOD-variable lights for use with FSX/FSX:SE. Unfortunately, due to technical limitations, they can't be implemented in FS9.

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Due to an issue with older releases leaving invalid data in the Placements.xml file, 4.3.05 crashed (when encountering such data). I've fixed the problem and re-released as 4.3.06.
I have just posted AFLT Version 4.3.08. It:
  • fixes a few recently-reported issues,
  • corrects the previous situation whereby very short links near intersections were not properly handled, and
  • add a variety of classic Canadian and US approach lighting systems.
If you have experienced the second issue at any of your airports, just reload and re-compile the airport.

I have just uploaded AFLT Version 4.3.09.

Shortly after posting 4.3.08 we were embarrassed to discover that runway edge lights along displaced thresholds were oriented incorrectly as were runway caution lights. This has now been fixed. As well, we discovered that when operating hours were specified, the lights were late in turning off. This too has been fixed in the new release.

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I'm very happy to announce the release of AFLT version 4.3.10. It contains a major improvement, a disappointment and several fixes - all detailed in the included Version History.pdf. I do, however, want to expand on the improvement and the disappointment.

First the improvement. Tom and I have spent a lot of time on developing a real alternative to BGL_LIGHTS as a light-source for FS9 and FSX. While there was not much we could do with standard effects, we have come up with a profile for inverse-mipmapped effects in FS9 and FSX which gives far more realism than BGL_LIGHTs. We urge you to give inverse-mipmapped effects a try - even if you've previously compiled your airport using BGL_LIGHTs. We think you'll be impressed. Please use the slider settings defined in the Installation section of the user manual.

Given our success with FS9 and FSX, I was hopeful that the same approach could be used with P3D, where effects are currently of little use as AFLT's light-source due to their very different internal handling in P3D and consequent very limited range. Unfortunately, that hope was short-lived. To make matters worse, I was surprised to discover that when using LOD-Variable lights as the light-source, for some as-yet-unknown reason, PAPI/VASI lights grow rapidly in size in the middle of an approach, creating a distraction. But otherwise, LOD-Variable lights do seem to offer a good alternative.

I've not given up on either effects as a light-source for P3D or fixing the PAPI/VASI light issue. But, I did not want to further delay this release. Given that preventative self-isolation for Covid-19 is keeping me close to my keyboard, I'm confident that, over the next week or so, I will find a solution to both issues.

My continue thanks to Tom Gibson for his extensive efforts in testing this release and to those users who have waited longer than expected for these fixes.

Hi, girls and boys. Version 4.3.11 is the final planned release of AFLT4. Everything is now working as intended - or as close as I feel I am able to make it.

My previous post regarding Version 10 was inaccurate in one regard. Inversely-mipmapped effects were not available to FSX. I have been unable to get them to work in either FSX or P3D. And the usual "standard" effects had insufficient visible range. So, I have adopted a multi-emitter approach. AFLT4 now uses 3-emitter effects for all Flightsim versions. While all effects are derived on-the-fly from the same base, this approach necessitates different effect parameters in certain applications. For example, the effect used in PAPI/VASI applications differs from that in other applications. You may find additional variations are required at your airports. So, AFLT allows easy customization of effect parameters in any application. This new approach provides very good results is FSX and only slightly less-so in P3D. Please refer to Appendix "D" in the user manual for details. Of course, the excellent rendering of inversely mipmapped effects in FS9 remains available. I also tried making LOD-variable lights available in FS9 and FSX. Limitations on FS9's handling of texture alpha channels preclude implementation of LOD-variable lights in FS9. It is possible to implement LOD-variable lights in FSX as simobjects (like in P3D). But, I tried this in AFLT3 without much success; the resultant overhead was prohibitive.

LM released P3Dv5 yesterday. To the extent PV5 supports the functionality used by AFLT with PV4, AFLT is fully compatible with PV5. Once I have had the opportunity to evaluate PV5, I may be able to enhance AFLT to take advantage of its new capabilities.

If you already are using AFLT4, this new release should be detected automatically. If not, it may be downloaded from my website http://stuff4fs.com.

Enjoy the additional realism at your airports.
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I have just made a new release of AFLT (4.3.13) to make updates required to read PV5 .bgls.

If you already are using AFLT4, this new release should be detected automatically. If not, it may be downloaded from my website http://stuff4fs.com.
Those of you following this forum will have seen reports of AFLT overwhelming Simconnect (with P3D) when it attempted to activate lights as the user aircraft came within range of an AFLT-lighted airport or, conversely, left the vicinity of such an airport. The main symptom was that the airspeed of the user aircraft was reset to 0 - with the expected result if the aircraft was off the ground.

I have redesigned the Simconnect application to "meter" these activations and deactivations so as not to overload Simconnect. By "meter", I mean AFLT initiates the first activation/deactivation but waits until Simconnect has responded before initiating the next one. Of course, this means that if you weren't plagued by this issue, things will happen at a somewhat slower pace. But since AFLT starts loading lights at about 24 nm from the airport, there should be no noticeable impact on performance - except possibly with large airports having thousands of lights. (Remember, if you don't have pilot-controlled lighting enabled - and why would you are a major airport - only a small portion of the AFLT lights are simobjects needing control.) Nonetheless, should you experience problematic delays, I can easily extend the distance at which lights are loaded.

As well, during this redesign process, I found several opportunities to increase the efficiency of the algorithm. So, you may experience a lesser impact on FPS with this new Simconnect application

AFLT Release 3.2.14 is now available from http://stuff4fs.com. If you already have AFLT, the update will be automatically discovered and downloaded with your consent.


EDIT: If you have used the previous version of AFLT, there is no need to recompile all your lights for P3D to get the benefit of the new Simconnect application.. Either simply copy the file AFLT (Simconnect).exe from your AFLT\P3D files folder into ..\Documents\Prepar3D vn Add-ons\AFLT for P3D, or re-compile one set of lights which will do that for you.
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Due to an oversight in the build process, the PV5 compatibility constants were not included in Version 4.3.14. Fixed in Version
As with any new complex and powerful application, as the user base increases, it’s not surprising that some deeply-buried “bugs” and “nice to haves” begin to surface. AFLT is no different. So, I’ve spent the past couple of weeks responding to those.

The result is AFLT 4.4.00 which, as well as having fewer “bugs” than its predecessor, also offers the following new capabilities:
  • display of surface-mounts for lights at ground level, and
  • runway and approach lights on all the time
  • self-metered spawning and deletion of Simconnect controlled lights.
For a more complete list of fixes, please refer to the enclosed Version History PDF

For current users, the new version should be detected automatically the next time you run AFLT. For others, Version may be downloaded from http://stuff4fs.com

I have just posted Release to my website http://stuff4fs.com . It addresses two issues.

Previously, you may have noticed a slight misalignment between runway edge and centerline lights and runway heading. You may also have noticed that runway end lights were placed slightly off the end of the runway. These errors were due to me not previously recognizing that Flighsim displays airport elements using a WGS84 projection rather than just using the "raw" latitudes and longitudes. Thanks to Arno, AFLT now applies WGS84 corrections and these misalignments and positioning errors are history.

While diagnosing that issue, it was discovered with P3D, if the user aircraft was repositioned a long distance such as from an airport in North America to an AFLT-airport in Europe or Asia, the AFLT-generated lights at the destination airport may appear floating in the air rather than at ground level. This was due AFLT not waiting until the ground level at the new airport (which AFLT needs to know for simobjects) had been determined and was stable. AFLT now waits before displaying the simobject-based lights in P3D.

Finally, moments after I posted this new release, I received a report that AFLT does not properly handle right-side PAPI/VASIs specified in .bgl and .xml files. and I have confirmed this to be the case. But fixing it will not be a trivial exercise. So, since right-side PAPI/VASIs are not frequently encountered and in any case can be added with AFLT, I decided to let this release stand and address the right-side PAPI/VASI issue in a subsequent release. Incidentally, for those of you who need a P-VASI for your airports, I am hopeful that AFLT will also support P-VASI's soon.
AFLT General Release is now available at http://stuff4fs.com. If you have already installed AFLT, the new release should be discovered with an offer to download the next time you run AFLT.
  • As noted in the previous post, an issue with PAPI/VASIs was discovered just prior to the previous release. This new release includes completely re-worked PAPI/VASI handling - including P-VASI support.
  • As well, an earlier release introduced the ability to optionally display images of surface-mount hardware. But, if two or more of those images overlap, flickering occurs. This release provides a revised Light/Line Editor that gives the ability to suppress the display of individual surface-mount images.
  • AFLT's lights are generally placed at 0 AGL elevation. But, if the terrain surrounding your airport is not relatively flat, the approach lights will not be in a horizontal plane as recommended by the FAA. So, a new control has been added to the Approach Editor that allows you to specify the elevation of the lights in the approach array. The default is still 0 (AGL) but a single click will change this to the ARP elevation (MSL). If neither of these serves your purpose, you may set the array elevation to any value you wish.
  • Finally, for those you who wish to tweak your project, for example to vary the elevation of individual lights, the user manual includes a new Appendix “E’” that details the encoding of Placements.XML. If numerous changes are required, experienced users may find it more convenient to directly edit Placements.XML than to individually edit each light. But, be careful! You could easily wipe-out the results of your previous efforts, and I will not be able to help you recover – which likely will require regeneration of the project.
Depending on the state of your project prior to installing Release 4.4.1, you may find (or have found) some duplicated taxiway lights or other anomalies in the AFLT or Flightsim displays. If this happens to you, or in any case if you haven't extensively customized your airport lighting, it is recommended after you install the new release you close AFLT, open your project in the AFLT projects folder, delete the files "Placement.XML" (if it exists) and "StockData.xml" and re-run your project. This will ensure all your lights are properly aligned and eliminate any duplicated taxiway lights.

I am hopeful this will be the last release for a while.

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I have just posted General Release 4.4.3 to http://stuff4fs.com. For those of you already using AFLT4, this new release should be "discovered" automatically the next time you run AFLT.

The primary reasons for making a new general release at this time were to:
  • resolve an issue whereby, when arriving at an AFLT airport from over higher ground, the lights were sometime floating in the air rather than being on the ground, and
  • eliminate the automatic switching of dimensional units from ft to meters and vice versa. You can now use whichever units you prefer for either ICAO of FAA approaches. Unless you direct otherwise, AFLT will convert, say, 100' to 30 m. and vice versa. If you inhibit such conversions, AFLT will always convert based on 3.28'/m.
To facilitate this latter enhancement, it was necessary to change the method for handling of approach elevations. Consequently, when you run this new version, if you have specified an approach elevation, it may no longer be correct. So, please check this parameter and update as necessary. (This is a one-time requirement.)

As well, this release contains a few fixes. Please refer to the enclosed Version History.

Version has been running as a development release for a couple weeks now with any issues being reported. So, I have promoted it to general release status.

This release:
  • finally solves the issue of floating lights. (I thought that issue had been solved in the previous general release, but no so.)
  • enables specification of alternating-colored centerline lights, and
  • makes the addition and removal of lights as you approach or leave an airport a gradual process, rather than the previous single step which could overload Flightsim at a very large airport and momentarily freeze the user aircraft.
I have just posted Development Release It addresses a couple of issues:
  • In earlier releases, on approach to mid- to high-altitude airports, approach lights would progressively disappear before the user aircraft reached them. This also happened at low-altitude airports but may not have been noticeable from the cockpit.
  • Moving, editing or deleting runway end lights, PAPI/VASIs lights or lines of approach lights could leave erroneous information in the database.
In the second case, now only individual approach lights other than those in the threshold bar and TD zone may be moved with the cursor and editing of those lights is restricted to changing elevation. All other noted moves/changes/deletions must be made using the applicable custom editor.

While the coding changes were generally simple and straightforward, those related to moving/editing/deleting lights were quite numerous. Hence, I'm making only a development release at this time in the hopes that a few of you will help confirm its "golden".
I have just posted AFLT Development Release to my website http://stuff4fs.com If your system is configured to check for development release updates, the new version should be automatically detected. If it isn't, you can download it directly. Be sure to select Development Release from the menu.

Some users have reported that Pilot Controlled Lighting (PCL) did not work in the earlier release. While investigating this issue, I discovered a couple other issues that could affect operation generally with P3D. Consequently, this new release includes major changes.

The only file changed is AFLT (SimObjects).exe. If you don't want to recompile your project(s), all you need do is copy that file into your Documents\Prepar3d vn Add-ons\AFLT for P3D folder, replacing the earlier version.

Please report any issues.

EDIT: If you choose to copy only AFLT (SimObjects).exe from the archive, you should also save a copy to your AFLT\P3D Files folder
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