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Guest johnnyboy62

Creating IFR approaches

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Maybe I'm stupid, but I don't think so. I am a trying to understand what has been written here about BGLCOMP and creating IFR approaches, but I find it very difficult. I have been using a combination of AFCAD and FS Scenery Creator to create a completely new airport from scratch. I am very happy with my work so far, everything works just fine, but I don't have any IFR approaches.I have some simple questions about this:1. Is it at all possible to create IFR approaches to an already existent airport (the one I have created using other programs) using XML files and BGLCOMP?2. If so, will the ATC use these approaches and assign one to me when I fly in to my new airport? I don't want only visual approaches.3. Is there some place on the internet where I can find useful information for bglcomp beginners about what the xml file should contain. I don't mean the structure of the xml file, I can read all about that in the BGLCompSDK document from Microsoft, which I have. What I want is an explanation of what all the attributes mean, for example "theta" and "rho", which apparently are required for some leg types. The information in the BGLCompSDK document is not enough!

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I will assume by existing airport, you mean a new airport you created and not a default FS2004 airport that you modified.1. Yes, you have to create the entire airport structure outlined in BGLCOMP so that all the elements are recognized by F2004. BGLCOMP provides two distinct functions, visual scenery and controlling systems. AFCAD provides a good example of visual scenery and controlling systems. AFCAD has the ability to lay down ground elements, i.e., taxiways, runways, aprons, and define controlling systems, taxiway paths, parking, NAVAIDS for ATC control. At the moment, AFCAD doesn't provide for more extensive controlling systems, such as, approaches, waypoints, etc. You can use FS2002 and earlier style programming tools to provide the visual scenery but not the controlling systems.Adding approaches is going to be a demanding task until someone designs a GUI style program to input the data. For a new airport, you need to define waypoints for approaches, plus the approaches. AI will only use a visual approach or an ILS approach. VOR, VORDME, GPS approaches are only for your use.2. If you are under ATC control, you will be vectored either to a visual approach or an ILS approach, just like the AI. If you want to practice the other approaches, then do it without ATC control or use the approach with ATC control but beware that ATC may cancel your clearance.3. Google search "ARINC 424" for information about the approaches. Rho (distance in meters or feet) and Theta (direction in degrees). In a CF leg:If fixIdent and recommendedIdent are the same, Rho and Theta are zero. Why! Because they are the same locations.If fixIdent equals one location, i.e., runway landing waypoint and the recommendedIdent equals another location in relation to the fixIdent, i.e., VOR, then Rho equals the distance from the VOR to the runway and Theta equals the direction from the VOR to the runway in this case.God's eye view, approach plates, and sectional charts are probably necessary to appreciate all the values needed to make just one leg segment of the entire approach.W. Sieffert

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Thank you for your answer!I understand from your answer that I need to create the whole airport using only xml and bglcomp in order to get what I want. In that case I guess I'll have to forget all about it, because I am not ready to throw away all the work I have done using AFCAD.

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Whoa!! Continue using AFCAD for those things that AFCAD can best do, e.g., laying down the ground elements - aprons, taxiways, runways, NAVAIDs.Use the BGLCOMP to write your approaches in a different XML file and compile separately.W. Sieffert

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Use the BGLCOMP to write your approaches in a different XML file and compile separately.So with the above information, is it then possible to write approaches that over ride what is supplied?? What I would LOVE to be able to do is kill the visual approaches to runway 26L and 26R into Honolulu and force the LDA all the time...Is it possible, or just never going to happen?Chris

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Hi Chris,I found out that AFCAD doesn't add the "deleteAllApproaches="TRUE" to the AFCAD file. Also I found out that using separate files with pieces and parts for the same airport caused ATIS to stop working. There could have been other anomelies that I didn' notice.I recommend placing everything in one file for an airport, as MS did with FS2004, except for flattens and terrain changes, such as road, utilities deletions.You will have to gain access to the AFCAD source file. How would one do that!!!???:-hmmmCheck the library!!!W. Sieffert

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Yes, I agree, AFCAD uses the command "deleteairport" for the "overriding" of default setups by layering. This "delete" name is confusing, because nothing is deleted, it is only "excluded". The default files are not touched by AFCAD at all.I guess, on purpose, it does not "delete" default approaches, so the approaches will be still there, even if you create a new afcad for the airport. AFCAD does override runways, aprons, apronlights, com frequencies, helipads, starting positions and all things related to taxiways and parkings. Now, if you edit (move or modify) default navaids, as long as you keep the same ident for the navaid, the edited navaid will appear instead of the default. If you change the ident then FS2004 will interpret it as a new navaid, and you will see the default and the new one, both working. For some reason, this editing does not work with markers at all, but it does with ILS, DME, VORS and NDBs.There is no way of *deleting* default navaids with AFCAD, the only possibility, so far, is to dig into the default file containing them by disassembling and recompiling. I have been using BGLXML by Alessandro Antonioni, for this purpose with good success, in my attempts to convert default LEMD into the new LEMD (working by the end of this year).I found that a default AP file contains all data for the airport (country, state, city, etc, runways, approachlights, vasis, ils/dmes, start positions, com frequencies, approaches -legs-, taxiways and parkings, waypoints, taxisigns, aprons and apronlights), some navaids (like terminal ndbs and markers for such airport), some library objects (visual scenery) for the navaids, and waypoints, nothing else. All the rest of the visual scenery is contained in other files.I have succesfully deleted offending default navaids and created my new ones (by disassembling with BGLXML, editing, and recompiling with BGLCOMP), and have noticed no ill effects on AI or ATIS, so far.Moreover, I have added all the provinces for Spain which were missing in the airport description, and it is working beautifully.The people from Airport for Windows, have in alfa or beta stage a scenery creator already in xml, called Scenegenx, if you want to try.RegardsJoaquin

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Interesting... so in theory then, if you delete the visual approach code for the runways, it should in theory always force the instrument approach??Chris

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ChrisI guess so, if you force AFCAD to delete the approach (again, disassembling and recompiling the AFCAD file, in order to insert the command 'deleteallapproaches="TRUE"'), then you will have the stock airport that you are modifying with AFCAD without ANY approach, and it will use the ones you program from scratch (not an easy task either). I haven't checked it myself, but I guess it should work like that.This is always a trial and error exercise, since MS is not giving out full information about how it works in FS2004.Maybe it would be easier to disassemble the default file of the airport you are modifying, examine the approaches you find there, edit them to your liking, and recompile again.The last version of BGLXML published today is still a little buggy, but it is coming near perfection very soon. The author is remarkable.

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Well I decompiled the Hawaii area, but there are no references to any "visual" approaches. The only approaches I can see are the actual instrument approaches (ILS, NDB, GPS, the LDA I was trying to gain access to)I have a theory to this visual approach thing into the area, maybe someone can come up with another creative way to kill the visual 26L and visual 26R approaches into Honolulu. Or kill the visual approaches in general through terrain and such.I have noticed that if the weather is greater than 3 miles or ceiling above 1000 feet, it will call for the visual approach to the runway. BUT if you have an ILS available, it WILL call for the ILS approach, and not the visual. I tried this experiment at Winnipeg International (CYWG) I set the winds for 314@36 knots, 5000 few, ILS 31 active, set the winds for 181@36 knots, 5000 few, Visual 18 in use..why? Because runway 18 in Winnipeg is an non precision approach... I then set an overcast celing at 1100 AGL, it called for a visual approach, lowering it to 1000 called for the non precision approach runway 18.Now getting back to Hawaii, the LDA 26L is a non precesion approach, and there is no IFR approach for 26R. So I guess what we are limited to here is if the weather is greater than what the sim wants for an instrument approach, it ignores any non precision approach available and forces the visual unless an ILS is available... anyone have any ideas on a workaround? Or is this buried into the ATC/weather?

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Visual Approaches are not defined. AI and User Aircraft, under ATC control, will direct you to a Visual Approach or an ILS Approach, if an ILS Approach is defined for the runway in use. Those are the only two conditions used by ATC. GPS, ILS, RNAV, VORDME, VOR., etc. approaches are all available in the GPS for your use, but ATC will only use visual and/or ILS when under their control.W. Sieffert

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So I guess the only way into forcing the instrument approach would be to some how make the sim think its IFR?? Is this possible without forcing it be IFR?? Like keep it 15SM vis, but force a variable in the sim to think its say 2 miles??Chris

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hi,as you know Hong Kong Kaitak is closed within FS2004 and I reopened it recreating all IFR approaches by the bglcomp.I can say step by step wath I found and consequently made.1)by AFCAD of Lee Swordy I reopened runways,taxiways,parking gates.Inserted a Tower point of view and after this assigned Comm frequencies.The ATC with a tower started to work.2)I inserted by the v.2.21 all navaids:ILSs only because all other navaids are already existing within FS2004.I found in the AFCAD help that into all MOD files it's also a file which disables the Stock and enables the MOD files. So when you start FS9 only the MOD files will work.At this point the ATIS was still announcing VISUAL approach for the runway in use,because the approaches were missing and AFCAD cannot create it.By the BGLCOMP SDK I made a separate .xml file with:IAF waypoints,approaches,approach legs,transitions,missed approach legs.Copied it into FS9/scenery/Asia/scenery everything now is working properly.If you compile only the approaches the ATIS will stop working.

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How does AI traffic react going into the airport? Does it follow the correct approach pattern you created, or continue a visual approach?Chris

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