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Adding Intersections to FS


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Does any one know how or know of a utility (payware or otherwise) for adding named intersections to FS9 and/or FSX?

 

I'm interested in permanently adding named intersections and GPS named waypoints (similar, but not quite the same) to FS. I'm not interested in temporarily defining them for indivdual flight plans, I want them added to the FS9 database of navaids so they display on the Map and GPS and can be grabbed and dropped into flight plans at will.

 

John

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Thanks, Rosario. It was a good try. I downloaded and used EasyNavs and it's a very interesting tool, but only deals in VORs and NDBs, not intersections. Thanks again for trying.

 

John

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Joe,

 

I know where those screens are from!

 

So, how did you add the obviously new intersections Joe and John? I can see all the existing intersections in the Flight Planner screens in FS9 that correspond to the FSX ones you're showing. That's the missing piece for me - how to add new ones. I can select the existing ones and drop them into the current flight plan until the cows come home. What I need to do - and don't know how - is to add new ones to the FS9 database.

 

John

 

EDIT: I see BGLComp.exe in my FS9 SDK but the docs file appears to be entirely devoid of any references to navaids, fixes, intersections or anything like that. Is there something more extenseive for FSX?

 

JDA

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Hi John

Do you have the FS9 SDK which includes the bglcomp.exe program?

Mine was made using the FSX SP2 SDK so would be of no use to FS9

I'm just going to send you a mail with an attachment.

Stand by one..

EDIT.. Sent!

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Update for any others who are following this thread. The FS9 SDK does indeed address this. They are referring to the intersections as "Wayponts" so my searches on "fix", "intersection" and "navaid" all struck out.

 

I haven't done it yet but it appears you can create a very small, simple XML file with Notepad and drag and drop that on the icon for the BGL compiler that is in the FS9 (and FSX) SDK. That creates a bgl file that you copy into your FS scenery folder and voila, FS knows about the new "waypoint" and you can include it in flight plans. It all appears relatively easy and feasible. I'll report back on the first successful one, but obviously Mutley made it work in FSX.

 

If you want to fly STARs and the native FS database doesn't have some of the intersections you need, this is one way to fix it. There may be others...

 

John

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Sounds like a good idea Rob, John did come back to me late last night by mail to start explaining how it works, whatta guy!

I think today is when John goes on vacation for a week so you may not get a reply for a while.

Cheers

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Phil,

 

It appears from the format for adding waypoints that they are precisely defined by the latitude and longitude you enter for them. Whether that would lie precisely on the relevant VOR radials would depend upon how precise your coordinates are and also on how precisely located the VORs are in the FS database.

 

I have run into many cases where following the specified radial does not lead precisely to the waypoint or destination expected. It's always close, certainly close enough, but not necessarily right on.

 

Two things to remember....

 

1) Great circle routes (used by the GPS and I think the FS flight planner) are not precisely congruent with a straight line on a map, regardless of the projection scheme used for the map. The greater the distance, the larger the variation between the map line and the Great Circle line. That difference is at it's maximum midway between the two points in question.

 

2) One degree at 60 NM subtends one NM. When defining intersections with radials, one degree increments are pretty "coarse" so it is quite possible to have a set of coordinates that do not lie exactly on the specified radial.

 

John

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Rosario,

 

Thanks again for your help in this...

 

I looked in some detail at the FS Commander product after you mentioned it. FSC appears to do what is needed to define and utilize user-defined waypoints within FSC itself, but I saw nothing that indicated that they are also added to the FS scenery database to supplement those already there. I'd prefer to be able to add to or edit the FS data.

 

I appreciate the tip and I wouldn't rule out FSC as a future purchase, particularly if I lose the ability to use my beloved FS Navigator, but it's not exactly what I'm looking for right now. It appears using XML code and the SDK BGLComp utiilty gives direct access for additions to the FS database. One open issue yet is editing existing FS elements, but I have no current need to do that. I'll cross that bridge when I get to it.

 

John

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Quote
...but does the FS9 SDK compiler allow you to set up a 'waypoint' that is precisely set up on radials from different VORs, like many in real life are?

 

Phil,

 

More info on intersections in FS. I've learned a lot since the original posting and one of the things I've learned is how little I know. You'll find this interesting with respect to your question, however.

 

Latitude and longitude can be expressed in degrees, minutes and seconds (DMS) or in decimal degrees. In the course of this search for enlightenment, I've run into both here and there.

 

The example XML source code in the doc file for the SDK bgl compiler that is used for adding intersections (and other things) uses decimal degrees and shows 8 decimal places.

 

When importing those same waypoints to FS Navigator, it also requires decimal degrees and uses only 6 decimal places. I have no idea what other third party flight planners might use.

 

When an FS Flight Plan is created by FS, the latitude and longitude parameters in that PLN file are back in DMS format and the seconds have 2 decimal places, implying precision of about 6 decimal places in decimal degrees.

 

In coverting back and forth between formats, rounding errors and the like inevitably creep in. Another source of errors will be changing magnetic variation at the VORs. Variation "creeps" and VOR radials coincide with magnetic bearings, not true bearings. It all comes back around to one of Allard's Laws of Power Plant Maintenance - "Constants aren't - Variables don't".

 

I've seen considerable error in some VOR data, e.g. flying a long leg FROM a VOR on a specified radial that supposedly leads directly to the airport, next waypoint, etc, but often it does not, by more than a degree, which is 1 NM at 60 NM range. It's almost always good enough but drives those of us who are anally precise up the wall.

 

NOTE TO ALL: I've cracked this, with help from others and I think I can put it into layman's English, so there will be an Article/Tutorial at some point. It's not difficult, but it's detailed. I think I can reduce it to instructions that the technically challenged can deal with.

 

John

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  • 1 month later...

UPDATE:

 

As promised above, after figuring out how to add intersections to FS, I've written an illustrated how-to article describing the process. If you're interested you can find it here...

 

http://mutleyshangar.com/features/jda/wp.htm

 

Mutley has done his usual fine job of formatting and fancifying, making my work look better than it really is. Have a look if you'd like to learn how to bring your FS back in synch with the real-world by adding intersections, GPS waypoints or other fixes. If you've been wondering about using XML this might be a good place to get your feet wet with that too - there's a tiny bit of it involved in this process, which is not difficult it all. It works in both FS9 and FSX. Have a look.

 

John

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Hi John,

From an "outsiders" point of view it is an excellently written article. Often when confronting unchartered territory the prospect of feeling confident about using it seems ominous but with your guide it seems so obvious!

Thanks for taking the time out to de-mystify this subject, I know I may have pointed you in the right direction but you have come up trumps with this one!

Cheers

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A very well written article John! I intend to (try) and add a waypoint over my house.

One question though, how can I accurately get the lat/lon details without slewing to my location in FS. I am assuming I could do it by using the google earth co-ordinates? I think the hardest part will probably be converting the lat/lon so that FS understands them. From my own experience when I converted some FSX flight plans back to FS9 (Mutley Field Adventures) it became apparent that FSX uses a much more precise lat/lon co-ordinates than FS9 does.

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Rob,

 

I haven't done any ad hoc fixes. I've used published sources for ATC-named fixes and haven't had any problems.

 

As for precision and accuracy (not quite the same thing) I'm not sure how to address that. FS9 seems to use decimal degrees to eight places, which is quite precise. Whether those locations align accurately with the coordinates for real-world terrain features is quite another question which I cannot address.

 

My sources for coordinates for the fixes that I have put into FS9 (almost 200 so far) are either the government (FAA in my case) sites or some third-party RW navigation aids sites, such as Air Nav. Both of those are giving me coordinates as D-M-S with seconds normally provided to two decimal places. I've just been converting those to decimal degrees to eight decimal places (see the appendix at the end of my article) and entering those converted values.

 

Frankly, I don't know how accurate the GE coordinates are either, given that they are only photographs and some angularity necessarily enters into it. In any given shot, only one point is directly beneath the satellite - everything else is viewed somewhat obliquely. I suspect that providing highly precise coordinates by scanning across that necessarily distorted image of the surface is going to be problematic.

 

Also, understand that for most ATC purposes, a few feet or even a few hundred feet is not a problem. Airways are eight miles wide, for instance - if you're within 4 miles of the centerline you're on the airway. Obviously things change a little if you're talking about a Cat. III localizer and glideslope, but for enroute waypoints, close is plenty good enough.

 

Remember too that your scenery is not necessarily precisely aligned to the RW latitude and longitude coordinate system. If you live on the bank of a river in the RW and try to replicate that exact point in typical FS scenery, you may very well have a flooded house. I would say the best reference would be to get a RW GPS reading for your house, but I wouldn't expect it to line up accurately with your FS scenery - that's probably asking too much of the sim.

 

John

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