Historic Aircraft and the endangered species of radio navaids

User Support Hub Aircraft & Systems
1

Sorry if this subject has already been beat to death, but I’ll go for it anyway as it’s my first post on the forum.
Hello to all, I have been a user of MS Flight simulator since the beginning, and a user of X-plane as well for several years now.

During the brief time that I have used this Sim, I have developed a concern regarding the unavailability of many radio navaids that exist in the older sims, presumeably due to de-commisioning and the fact that MSFS uses continuous updating to the latest AIRAC cycles whether the user wants them or not.

I now have 3 sims on my computer: FSX, X-Plane, and MSFS. One of the things I have enjoyed the most over the years is learning and flying historic airliners. On FSX, I fly the Captain Sim 707 and 727, as well as the A2A Constellation. On X-plane, I fly the 747-200, 737-200, and an excellent freeware by AiroWorx DC-3.
One of the things that has bothered me since starting on MSFS, is the attrition of traditional radio nav-aids. I decided to create this post in the event others share this concern, and to present my solution, however limited, to this issue.

For FS2020, I recently purchased the JustSim BAE-146 and my sites are also set on the PMDG DC-6, and the Boeing 247d by Wing42.
But I do not wish to be forced to fly these airplanes with GPS. I want to fly them as they were flown in their day. It appears that in many cases, due to the depletion of radio navaids, for many routes, it will be impossible to navigate using VOR or NDB without filling gaps using GPS. I do not have this problem with FSX, as the Nav database goes back to 2006. Nor with X-Plane, as the Nav database is comprised of text-files which can easily be edited to add missing nav aids.

An example of what drove me to this effort is a flight I recently planned for the BAE-146-200 to go from LTBA (Istanbul) to UUDD (Domodedovo).
On the BAE-146, I am only using radio Navaids. In the past, I have flown this route on FSX using VOR’s and NDB’s. Some of the spans approach 180 miles, but flying high enough, it was do-able. On MSFS with the NavBlue database, and also with the Navigraph database, a couple of crucial VOR’s are missing. These are; ODS (113.95) and DNP (112.5). These VOR’s do exist however, in the 17 year-old FSX database.

I decided to make an attempt to alleviate this problem for my self as follows.
First I decided to do an analysis of the three databases: MSFS/NavBlue Airac-2304 (sorry, it was latest on my machine when I did the analysis), Navigraph AIRAC 2305-R1 (for MSFS) and FSX (files dated 2006). I excluded X plane because of the much different file format.

To this end, I wrote software which extracts the appropriate .bgl files and analyzes them in terms of VOR, NDB, and ILS presence, and then computes a tally for each bgl file, each ICAO region and each ICAO country code while comparing the 3 databases.
I created several spreadsheets, one of which lays out the 3 databases side by side and readily reveals the differences and gaps. One can easily see the attrition between Airac 2304 and 2305.

The results were rather surprising (to me). If there is interest by anyone in continuing this thread, I will be happy to share this spreadsheet and my findings in more detail.

I next determined that I can can borrow NVXnnn.bgl files from FSX to package-up as mini-addons in the Community folder to fill gaps when I need particular VORs or NDBs to achieve a flight plan without using RNAV.
I do not wish to mess with airport files or ILS’s because of possible alignment differences between FSX and MSFS. There are, however, many missing ILS’s, presumabely replaced with GLS.

So, for the flight plan I mentioned above, I was able to create an overlay package by hand (addon) to place in the community folder to restore the missing VOR’s . I have been able to do this with other routes as well. Once finished with the flight, I can easily remove the addon to restore to default.

There are caveats however. First, I was not able to make my addon compatible with Navigraph. Next, one would need access to a copy of FSX.

I might note that another forum member on the AvSim forum attempted to create a similar addon to restore a VOR using the SDK’s facility for creating Nav Aids. He did produce an addon package, however, there was a problem with the tool defaulting to creating a DME-Only station rather than a VOR-DME. This was despite that he specified to the tool that it was not a DME-Only. I don’t know if further work was done on the SDK since May when this experiment took place.

Hopefully, others on this forum will find this subject of interest. For me, it is the biggest reason that I did not immediately abandon MSFS.

12 Likes
2

Hi!

Wow - the fact that I was just searching this topic, and just seen your post - incredible coincidence.
All I can say, is that you are not alone! I always fly via VOR (unless the Boeing 247D, so fly-by-ear), and I’m also worried that VOR stations are going away year-by-year.
Little Nav Map is able to display whatever VOR / NDB stations you have in the simulator - so this would solve the issue of flight planning, once the VOR stations in the sim.

I would be really interested to have as many VOR stations in FS2020 (and since it will be compatible, FS2024). Even if those stations have been decommissioned since the FSX days, I don’t care. I have done several Coast-to-coast USA flights since 2002, always using VOR’s, and I would like to be able doing this, and futureproofing the availability of VORs.

The fact that Black Square addons exists, shows that there is interest in non-GPS navigation, and saving VOR stations (even with the help of the FSX database) is something I would love to have.

Please share anything you have and willing on this topic - I say it’s time to get our VOR’s back!

3

Yes it would be really helpful if we had a choice of Nav data. Not loads of choice but just perhaps the most current that MSFS has which we have now and a legacy from when there were the max number of radio navaids. Even if that involved a sim restart between changes I wouldn’t mind. Navigraph can load a different data set so perhaps that method is the way forward if it’s not to be rolled into the base sim.

4

Obviously you’re not allowed to share FSX files, but if you could outline the process of how you used the .bgl files and made them work in MSFS that would be very much appreciated!
I know that (lucky) both use this format, however just copying a .bgl into the community folder is unlikely to work (I think). Do you need to create a new scenery using Developer mode?

5

I’d certainly like to see the VOR/NDB stations re introduced to simulate what was available when these older aircraft were flown.
I would like to fly the 146, the new DC6, the new F28 etc how they were flown in the day with a full array of VOR/NDB stations.
I was quietly lamenting, only last week, the shortage of VOR stations across Northern UK.

2 Likes
6

I did think about this approach but realized that VOR stations change course year by year unless they are recalibrated. Therefore some flight planning software may not be compatible. Also, how do you plan a VOR-VOR flight if those navaids do not exist in Simbrief or the like. Seems like LNM is the only way to read in-sim database. I guess having a VOR gap is nothing wrong and indeed US sectional charts sometimes indicate a VOR gap on longer routes.

7

I’d personally still want them back.
Giving back FREEDOMS TO is always better than taking away opportunities.
If you don’t want to use them, that’s fine, but there are people out there, who do, even if there are some caveats.

1 Like
8

I’ve looked into this. It seems that the files we are after are the NVX navdata files, not the APX and ATX files.

9

Flying the old way with VOR’s is why I still have FS9 with a bunch of addons on an old computer and use it quite a bit. I love using the B727, B707, and the DC-9 the old fashioned way. I wish someone would introduce a good B727 for FS 2020. I would buy it in a heart beat.

2 Likes
10

Thanks for all the responses. I still feel that those of us interested in this are in the vast minority within the sim community. I’m really surprised that the developers of historic aircraft, such as PMDG or Just Flight are totally silent on the subject since they have a stake in this. PMDG addressed it in the DC6 by modelling modern radios and GPS (yecchh), and I believe that Just Flight provided an optional FMS.

I’m a bit paranoid about the legalities of sharing information. For example, the spreadsheet I built with the 3 databases summarized side-by-side. Am I safe in sharing this? If so, can someone help by allowing me to email it to them and then, somehow, the recipient shares the file here?

I can also provide a skeleton framework for the mini-addon that will allow the user to simply copy in the appropriate NVXnnnn.bgl files and fill in the blanks. I use nothing more than a text editor to create the addon. (BTW, vi is my text editor of choice (available for Windows as GVIM). Been using it since the 80’s when it shipped with unix). Please let me know if zip files can be shared in this forum, or if some other format is better.

Regarding the availability of FSX Nav data. I believe that for a reasonable sum of money, FSX can still be purchased on Steam… (?) Not sure if it will contain the same version of the Nav database as it did when it was shut down my MS.

If one wanted to create an addon with a substantial amount of coverage, FSX has a number of limitations. One cannot blindly copy in all of the nav database NVX files for the following reason:

The results will vary depending on the region that you want to restore 2006 navaids. If you want older NDB’s, you will get plenty. For example, for the U.S, NavBlue-2304 has 864, Navigraph-2305 has 507, while FSX has 1696. For Southern Europe, NavBlue has 566 NDBs, Navigraph has 470 NDB’s and FSX has 848. Most regions will gain many more NDBs than exist today.

In terms of VORs, for the U.S. NavBlu has 1032, Navigraph 1036, and FSX has 1086. For Europe, FSX has approx 15% LESS VOR’s, however FSX recovers many VOR’s that no longer exist.

For Australia FSX recovers approx 50% more than the present VOR complement. For China, Russia, the Far East, and Africa, FSX lacks considerably compared with the newer databases.

I also noticed that for much of the world, the Navigraph database is missing the conversion of many VOR-DME’s to NDB-DME’s. Not sure why. The NavBlu database did catch these.

If one were to build a complete addon the disparities would need to be considered on a region-by-region basis foloowed by a decision of whether to overlay an NVX file.

Someone mentioned VOR gaps. To me, these are unacceptable if one is flying without GPS. (Though it does add an element of adventure to the flight).

I do feel that given some software, one could build a complete nav database addon that incorporates the nav-aids that are missing today but present in 2006 and which also contains the Nav aids that have since been added. An added benefit would be that it would freeze the forward-marching attrition. It would take a fair bit of work to do this (and probably, a lawyer).

Cheers

11

Sorry, I didn’t address all of the questions that came up in the thread.

Regarding the process for creating the addon:
(Prepare to get some painful detail…)
You build a directory structure to go into the Community folder, eg
xx-Johns-NAV/ContentInfo
xx-John-NAV/scenery

(you can name the addon anything you like)

then within ContentInfo you create a sub-directory with the addon name
xx-Johns-NAV/ContentInfo/JohnsNAV

within JohnsNAV you add a .json file named ContentHistory which contains:
{
“package-name”: “JohnsNav”,
“items”:
}

and you also add a .jpg thumbnail image  (mine is 18.8 KB in size)

In the /scenery folder you add a sub-directory: fs-base-fsx

in fs-base-fsx you add one or more subdirectories whose name corresponds to the QMID ID
(Q-Mesh ID) of the NVXnnnn.bgl file that you are adding to the sim
for example, if your missing VOR(s) are in NVX07010.bgl, you create a structure:
scenery/fs-base-fsx/0701/NVX07010.bgl

If you need multiple NVX files, you can add more QMID folders, ie,
scenery/fs-base-fsx/0701 and scenery/fs-base-fsx/0801

the .bgl file name will correspond to it’s directorie’s name

copy the appropriate NVXnnnn.bgl files into their respective sub-directories

Finally, back to the top-level xx-Johns-NAV you need to add a layout.json file and a manifest.json file

the contents of layout.json will look like:
{
    "content": [
    {
        "path": "ContentInfo/JohnsNav/ContentHistory.json",
        "size": 49,
        "date": 133309819486870266
    },
    {
         "path": "ContentInfo/JohnsNav/Thumbnail.jpg",
         "size": 19295,
        "date": 132900169460000000
    },
    {
        "path": "scenery/fs-base-fsx/nnnn/NVXnnnn0.bgl",
        "size": xxxxxxx,
        "date": 133309819486830379
    }
    ]
}

where the sizes correspond to the files that you provided. and where nnnn corresponds to the id in the .bgl filename (for example for NVX07010.bgl, nnn = 0701

also, to the xx-Johns-NAV top level, you need a manifest.json file which looks like:

{
“dependencies”: ,
“content_type”: “SCENERY”,
“title”: “xx-Johns-NAV”,
“manufacturer”: “”,
“creator”: “Me”,
“package_version”: “0.1.0”,
“minimum_game_version”: “1.32.7”,
“release_notes”: {
“neutral”: {
“LastUpdate”: “”,
“OlderHistory”: “”
}
}
}

2 Likes
12

Regarding flight planning:

I’m sure you will all think that what I do is ridiculous:

I hand build my flight plans, on paper, including SIDs and STARs.

First, I make an initial cut using the FSX Flight Planner.
Then I consult actual airport charts on line and choose a SID and STAR for each runway.
I add the waypoints to my flight plan, but instead of specifying RNAV waypoints, I specify in terms of a VOR radial and DME distance from an appropriate VOR.
Then, I cross check with the MSFS World Map via my spreadsheet. This tells me if I need to create a mini-addon.
I write a plan based on the combined navaids of FSX and MSFS.

Finally, I save my flight plan (.pln file).

When flying, If I have no FMS or electronic map, I refer to my paper-flight plan.

Crazy huh?

2 Likes
13

I think it is very important to preserve disappearing VORs, DMEs and NDBs.

If I had a free wish I’d want to have a mechanism to activate navaids by year, or at least by 5 or 10 year intervals. As an example, if I fly LTUs F28 to LOWI in 1969 I would like to have a navaids representation as it existed by 1970.

Dreaming…

2 Likes
14

I’d be interested in a historic NAVAIDs set running several decades. However, you’re going to run into the fact that airports have changed a lot as well and the old approaches will lead you nowhere.

It’s almost like we need an entire scenery set for 1960, 70, 80, 90, etc. I’m not sure how much of the airport, airway, and approach infrastructure is archived, and even less how much is digitized prior to, say, the late 90s. What’s crazy is how much stuff changes every 28 day chart cycle, much less every decade, so no matter what, you’re only catching a snapshot.

I do have a lot of old airport/facility directories, sectionals/WAC charts, and terminal procedures dating back to the early 90s, and scattered stuff prior to that.

Good luck with that!

15

That’s great, big thank you for that!

I’m on holiday now, but before we got going yesterday, I have found this software Easynavs. It can take FSX navdata out of bgl files, and recompile the files (in FSX format again, but thats not a problem, since in your experience MSFS can read them).

I took all the NVX files, copied them into a single folder (a breeze with Total Commander). Feed them all into Easynavs with one click as a folder. Now, at this point I didn’t have more time to tinker with it, but it seemed like that I could have recompiled all of that into a single, giant bgl. Since that would be a totally new file, this could be shared freely, even as a scenery just as you can share freeware repaints for FSX, as they are newly created data (even if some data still originates from FSX itself, just like with repaints, where the rivets and joints were painted on by Microsoft).

When I’m back from holidays, I have a look - I think it had around 4000-is VORs, and 5000ish NDBs, however many where duplicates - the numbers you have cited are probably more accurate. One bgl file could cover the whole globe, and we could dodge disappearing navaids. I’m not sure what would happen if the navaid already exists in MSFS, but I think the addon scenery would overwrite it. I believe magvar (magnetic variation) data is stored separately somewhere else in the sim, and applied automatically based on location (magdec.bgl, the site I’ve found also has solutions for that, even for MSFS). I did not see an option where you could set per-VOR magvar. The software also has the function to manually add navaids yourself, then compile them into a bgl, or add to the aforementioned list. Some with enough free time on their hands (definetely not me) could theoretically create historic VOR packages like this.

1 Like
16

Oh, and there is nothing crazy about building flightplans on paper. If at this stage our lives real flying is not feasible for various reasons, then simulating it is the next best thing. Especially today, if someone can afford VR, and trains themselves not to get sick, it’s amazing. Many enthusiastic people are taking this hobby very seriously, there is nothing crazy about it. There are many destructive hobbies out there, at least this one isn’t.

2 Likes
17

Thank you Peter. I will start looking into your solution, it is quite a revelation for me.

Like you, my time to spend on this is quite limited, despite the fact that I am retired. Seems I have less free time now than when I was working.

I’m not so sure about a giant .bgl file. Would the sim be able to handle it? How would it affect performance? I have no idea how the sim handles nav data in real time…

The main thing to keep in mind is the difference in FSX coverage on a region-by-region basis. I’m not sure that an addon that includes a given NVX file will not completely occlude the contents of the corresponding NVX file in the default database. So, if for example, you specify an NVX file in China, you may gain a few NDB’s but you may lose everything that has been created after 2006.

I have seen conflicting results with my mini-addons which will require a bit more investigation on my part.
For example, I used an NVX file from FSX to restore the FRZ VOR in Italy. But when I activated the addon, it occluded the corresponding NVX file, and I lost Nav aids that were not in the FSX file.

However, when I did the same thing to add the ODS and DNP VOR’s in the NVX07010.bgl file, I was still able to see the DMD VOR which IS in the MSFS NVX07010.bgl file, but is NOT in the FSX file. Totally confusing.

It would be nice to know how MSFS handles the NVX files in real time execution.

I would like to pursue building this addon but knowing that it will take quite a bit of work to merge the old and new databases. I would advise to save a snapshot of the earliest AIRAC cycle on your machine.

Regards,
John

1 Like
18

Hi John,

Right now it’s only a theory from my part (as I’m in an Airbnb, away from my PC until Tues), but by making a new database file with a new filename for the resulting bgl, no MSFS data should be occluded (as there are no conflicting file names).
When I said ‘giant’ file, I only wanted to exclaim, that there will be a single, bigger file instead of small, regional ones. I highly doubt that it can grow crazy large (I mean the WHOLE scenery folder on FSX was 10GB, and that included a lot more stuff than just navaids. We now have single addon airports that 4GB on their own, I don’t think performance will be an issue).

I have never used separate Airac products back in my FSX days, as I’m only a semi-serious simmer. I mostly fly GA (and the occassional PMDG 737), but never cared about how fresh my Airac cycle is. However since I always fly by VORs, (love the somewhat uncertain nature, plus the requirement to do the leg work, versus a GPS which just spits out where you are - safer, but boring, and it’s not real life anyway), slowly disappearing VORs suddenly meant an existential crisis for my type of flying, and just enjoying MSFS in general. Now it looks like I can stop the passage of time, and can futureproof things, as long as MSFS will read FSX bgl files (or until someone writes a converter, if that would change). Will see, but I’m very excited about it. Of course, stuff like that has to happen on my holiday, but that’s just Murphy’s laws.

I mean if we can use radio range navigation from the 1930’s, a whopping 90 years ago, then why should we forfeit VOR navigation?

I’m sure a lot of people don’t like Little Nav Map, but it’s free, SURPRISINGLY robust, and it’s a must have for any futureproofing project, as it’s not based on any online database. This is why Wing 42 recommends it with their Boeing 247.

I have used a lot of Skyvector, but the disappearing VORs will probit me from doing so.

1 Like
19

I just did some experimenting, and good news! There is no evidence of occlusion, even with matching file names. I was clearly mistaken when I thought I saw this earlier. I double checked with multiple regions.

I’m guessing that the “regional” subdirectories within the “scenery” directory , ie. directories whose name embeds the Q-mesh ID of the square that MSFS is flying into are only read-in when the airplane flies into that mesh-square? That would make sense for the sake of performance, I think. Therefore, I’m guessing that it would be important to maintain the same structure within a new addon. Navigraph seems to do the same thing with their addon.

Also, I did determine that the actual filename of the .bgl file is not important. MSFS seems to parse it and incorporate it into the map regardless of the actual name.

20

Just for everyone interested watching: I’ve contacted John, and we are working on this to make it happen, and quite possibly available to the masses as a mod. I’ve already had success integrating VOR’s and NDB’s from 2006 (guess why that year), as a scenery for MSFS, but there are SOME duplicates. A copy of FSX, it’s SDK (included on the CD), and Easynavs are the 3 tools you need to make it happen, if you want to compile things into a single .bgl, and it works.

3 Likes