Approach Light System Visibility problem

#1
I would like to report some other problems I found testing the last version of AFLT.
After I generated the array and the library (using BGL_Lights), I started FS9 and I selected night time.
I did not operate with the new LOD-variable options because I'm not sure I completely understood the meaning of the 3 values available. In particular Light Size (m.) - Min and Max. I did not find any clarification on the user guide and I supposed that are values for an expert.
Anyway, I think that Range 8 nm should be that I could see the light till about 8NM from its position more or less.

This is the first thing I noted starting the simulator: some lights disappeared just flying over them, others start to disappeare after a few miles out. It seems It depend on the altitude with which I overfly the scenery (I made some screenshot at different altitudes between 850 and 3000ft and moving between over the field and 6.3NM out to see what happens.

Clipboard01 is about 1.5NM from the approach light system at 950ft, as you can see only a part of the approach light is visible.
Clipboard01.jpg
Clopboard02 is near the approach light system at 950ft, as you can see a bigger part of the approach light is visible.
Clipboard02.jpg
Clipboard03 same position as 02 but 1550ft. All the approach light system became visible.
Clipboard03.jpg
Clipboard04 about 4NM out 1500ft, only a part of the approach light is visible.
Clipboard04.jpg
Clipboard05 5.7NM out, 1500ft, the approach light system is almost disappeared.
Clipboard05_5.7NM.jpg
Clipboard06 5.7NM out but 3000ft. The approach light system is visible again.
Clipboard06_5.7NM.jpg
Clipboard07 6.3NM out 3000ft, I think this is the limit at which the ALS becames invisible.
Clipboard07_6.3NM.jpg
Clipboard08 850ft in proximity of the ALS. It is noticeable that a parte of the lights is visible and a part not even if the 3d objects of the ALS is visible.
Clipboard08.jpg

After 6.3 NM (measured from the BEG Vor DME 114.95) the lights in any case disappeared more or less in the same way they did it using those generated with the older 1.1.03 and 2.1.01 AFLT versions but with the older versions I did not have those kind of visibility problem.
So is there something I did not understand in the meaning of RANGE option?

In an old POST I was searching for mor eindication related to the range and visibility angle (horizontal and vertical spread) parameter but without any answer. I'm not sure which are the references of this two spread angles. Maybe this could be the reason for which I have those strange effects flying over the area?

The second thing I noticed:
in the INI file generated during the Array procedure, there is a repetition of the LOD-Variable Size - Min (m.)=2. I was expecting there should be also a line for the MAX (as per LOD-Variable parameter selected to Default in the main window). Is it possible that it could be a bug?
 

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gadgets

Resource contributor
#2
First, the FS9 compiler issue - I'm too embarrassed to discuss it other than to say I've found and fixed it.

in the INI file generated during the Array procedure, there is a repetition of the LOD-Variable Size - Min (m.)=2. I was expecting there should be also a line for the MAX (as per LOD-Variable parameter selected to Default in the main window). Is it possible that it could be a bug?
It was an oversight and also has been fixed.

This is the first thing I noted starting the simulator: some lights disappeared just flying over them, others start to disappeare after a few miles out. It seems It depend on the altitude with which I overfly the scenery (I made some screenshot at different altitudes between 850 and 3000ft and moving between over the field and 6.3NM out to see what happens.
If you are using BGL_LIGHTs as suggested by an earlier post, range has no effect on them. Range is only effective with LOD-Variable lights. Also , if you have elevation or orientation restrictions (i.e., horizontal and/or vertical spread specifications), I'd expect aircraft position/altitude to have some effect on whether or not a light is displayed. Unfortunately, I'm not going to have time to diagnose specific cases; I'll have to leave that challenge to you.

Please download and use Development Release 3.1.02(d). I will have occasional access to e-mail over the coming weeks and will attempt to respond to any queries.

Don
 
#3
Thanks Don, you do not have to feel embarrassed, an oversight can always happen. Your work is very usefull.
If you are using BGL_LIGHTs as suggested by an earlier post, range has no effect on them. Range is only effective with LOD-Variable lights.
Ok, so I learnt another thing.
Also , if you have elevation or orientation restrictions (i.e., horizontal and/or vertical spread specifications), I'd expect aircraft position/altitude to have some effect on whether or not a light is displayed.
Yes, I have them for the approach light system, but using the same .def file as I did with the old version of AFLT, now it seems there is some difference. I'll make experiment to learn more about them.

But is there any chance to know what are the reference axis from which calculate the angle of spread? Because till now with the old version (in particular using v1.1.0.3) it was not so clear.
 

gadgets

Resource contributor
#4
Non-omni-directional lights are usually oriented in the direction away from which they are nominally viewed. For example, approach lights are oriented in the direction of the runway to which they apply. Directional limits are automatically referenced to the orientation.

Don't be afraid to experiment. (I'm going to be an infrequent source of info over the next few weeks./unreloable

Don
 
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