[RELEASED] U.S. Golden Age of Air Travel - 1958 navaids

Refer to this post for information about release:


Are you a fan of Classic Propliners making their way through the skies in the late 1950s?

Are you worried where all the classic navaids (VORs & NDBs) go with every AIRAC cycle update?

Then you may have just stumbled over a right thread for you!

Why

Recently, when crossing the U.S. following the 1953 United Airlines timetable westbound, I wondered on a couple of occasions how great it would be to replicate such flight with historically correct navaids following historical aeronautical charts.

Even though one can use today’s navaids and work around the fact that many VORs and NDBs are gone, the immersion sure would be on a different level.

And that’s when I decided to kick off my new MSFS project to replicate the navaids (VORs, NDBs and LFR / RRN) as they were installed in the contiguous (lower 48) U.S. in 1958.

The main idea was to be able to:

  • take the period charts (challenge: find relevant source)
  • fly correct period radials and headings (challenge: re-define magnetic variation in MSFS as of late 1950s)
  • use period approach charts, where possible (challenge: bring in the terminal navaids from these charts)

Sources

With the help of people over at CalClassic forum, I was able to find some approach charts from 1950s and 1960s and get ideas where to look.

That’s how I found scans of US Sectional Charts hosted by the Library of Congress. This is a sample of a map covering San Francisco area from April 1958 (downscaled):

And on Google Books I found Airman’s Guide listing various airport and navaids related information.

I also bought US Radio Facility Charts from April 1958 from ebay to complement the above (still on its way).

How

With the sectionals georeferenced in qgis, I was able to georeference the depicted navaids and create a navaid database as of April 1958 (approximately) enriched with the data coming from the Airman’s Guide (ranges, ILS data, LOMs, LMMs, markers…).

It is a time consuming work and for the moment I created a test area seen in the qgis screenshot above - California, Nevada, Oregon and Washington (+ Hawaiian Islands and two smaller test areas around Boston and Miami).

As for historical magnetic variation, Hervé Sors from aero.sors.fr was kind enough to generate magdec.bgl which brings the MSFS magnetic variation model to 1950s. This is crucial of course in this kind of a project as the magnetic pole moves constantly thus changing the magnetic headings flown. It works pretty well I have to say and I also found that there is not much difference between magnetic variation for the U.S. as of 1950 and 1960 (feel free to check for yourself).

So what

At the moment, I have a MSFS scenery introducing almost 300 navaids as of April 1958 over the territory mentioned above. The scenery includes correct historical magnetic variation which allows to prepare a flight with the 1958 sectionals and actually fly the route with correct historical VOR radials, magnetic headings and ILS inbound headings.

Currently I am conducting test flights to see whether everything works as intended (it does so far).

Here I am on finals to rwy 07 in Santa Barbara. If you can make out the runway :slight_smile:

A fun fact: As you can see in the screenshot above, I was able to make a custom map for LittleNavMap. Not really necessary but maybe useful for planning and in-flight. The blue line shows a part of one of my test flights.

So far, I was able to plan the flight with the historical sectionals, use the depicted radials to follow the airways, fly corresponding magnetic headings and in the end land in KSBA with the help of period ILS (got a 1958 middle marker signal too; only forgotten to tune the LMM frequency to ADF radio).

Limitations

This is experimental stuff and perhaps it remains such. Why?

A 1958 navaids cannot easily co-exist with the stock MSFS navaids (many may have been moved but still share the same frequency, many share frequency with a different navaid in close vicinity, same for ILSs…).

So, unless I find a different solution, I resorted to using a DeleteNavigation element described in the SDK as “only meant to be used for debugging your own projects and should never be published as part of a public package”. Here we go. It contains commands to delete all navaids around the World.

So while the 1958 navaids scenery works as intended, outside of the scenery area there are no navaids. As the SDK does not allow for deleting navaids from specific regions only, this is the only way I can make it work in MSFS.

Another limitation is related to the fact that some historical approaches may no longer be possible to fly in the sim. The landscape and structures on it are unchanged. So while a hill probably has not moved (much) over the last 60 years, there may be new antennas and man-made structures in the way of some historical approaches. I personally yet have to see such approach (I suppose the minima were higher in 1950s when compared to those of today). Nevertheless, for sure some runways are gone making corresponding approaches obsolete.

Is it worth it?

It is of course possible to fly classic propliners with the current AIRAC cycles. This is also demonstrated by my 1953-style crossing of the U.S. linked above.

So for some, the effort may not be worth it in the end.

However for others, using the historical materials to prepare a flight and eventually fly it might add yet another level of immersion not experienced so far.

I personally fall in the second basket, so to speak. Moreover, I enjoy very much researching this subject and finding a way how to implement it in the sim. So for me, the path is the destination as the saying goes…

This is a personal choice which comes down to preferences. One can always decide not to use it :slight_smile:

Besides, many classic navaids are disappearing with every AIRAC cycle.

Just to illustrate: In California in 1958, there were some 58 NDBs (incl. LMMs and LOMs). Nowadays this number goes down to 23. This impacts also NDB approaches of course. According to data available, there were almost 700 NDB approaches in the U.S. in 2014 but in 2024, according to official data not even 200 of them remain.

Plans

With the test area working as intended, I am thinking what next?

If the time and enthusiasm allows, I will progress with other sectionals. With 19 already done, I am about 20% through the entire lower 48.

One untouched topic is the Low-frequency Radio Range Navigation beacons. This tech, very much still in use in 1950s, was brought to MSFS by @ElectronVolt714 and his Radio Range Navigation addon. ElectronVolt replicated the RRN network with data coming from 1944. The 1958 sectionals reveal that many beacons changed place or frequency (or both) or beams or disappeared altogether. With the data I have, I can (and most likely will) update the RRN database used by ElectronVolt’s RRN addon to reflect the network as of 1958.

Where to get it?

Nowhere for the moment. I will release it in the proverbial two weeks on fs.to once I package it appropriately. Probably with a big EXPERIMENTAL and USE ON YOUR OWN RISK all over the place.

Thoughts?

I am happy to hear your thoughts about this undertaking. Please feel free to express yourself.

Thank you!

23 Likes

Wow.

That is one serious project and I totally respect your dedication and passion for such an undertaking.

I’m loving the vintage documentation you’ve shared images of.

This is reminding me quite a bit of the radio range element included with the B247D.

Respect :fist:

As an aside, it’s interesting to ponder those “not operational” vintage radios in the DC-6…

Another thought… could your add-on be made to replace the NAVBLUE AIRAC the way the Navigraph add-on does?

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I applaud the work you have done so far, Apollon0011. Back in the FSX days, I really liked flying old aircraft to custom mid-1900s airports using modified navaids representative of that time.

I wish that MSFS would incorporate the concept of eras into the sim. It would make what you and other community & 3rd-party developers are doing so much easier. If MS/AS added an “eras” tag to the metadata of an object - be that scenery, aircraft, navaids, etc. etc. - which specified an enable start date & disable end date - and provided an option in the MSFS GUI for users to choose a time period to fly in, then one could fly entirely in the present or any time period in the past. There would have to also have to be a conflict resolution process put in place to decide which object was displayed in cases where the eras metadata overlapped.

I look forward to seeing your progress is this endeavor! :mage:

Edit: FYI, there is a wishlist related to this topic: Historic airports, aircraft, flights, eras etc for MSFS

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That’s the right environment for our classic aircraft with no GPS. DC-3, DC-6, Caribou, Beech 18, Electra, B247D, …

Very, very interesting!

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Good point. I hope it could.

Let me have a look at it.

I am not sure whether there are tools capable of de-compiling MSFS bgls (we had great tools back in FSX) to sneak inside to see how they do it but I can always reach out to them and ask nicely :+1:

Though since they replace the navaids in the whole World, they may as well be using this “delete all” element :thinking:

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Very encouraging! A worthwhile project and I’ll certainly be watching it. Great work!

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That West-bound timetable alone is worth it’s weight in gold, in terms of giving idea’s on what to do in Flightsim. Schweet find! (also an awsome story on the other website of your flights!! Thanks!)

The fact you are taking it to 1950’s levels is just beyond my grasp of thought.
In seeing Kermit weeks fly from California to Florida using sectional maps, was a real inspiration to me already, making me seek these sectional maps(from the .gov website) and using them from time to time is already exhillerating. Combining those 1950’s charts with the period correct nav-aids is something completely wonderful.
It’s the “what have you gotten yourself into”-factor that makes this one of the more astonishing projects… and in all honesty, personally, i’ll probably only use the timetables to set up flights as i’m prone to “squirrel” on just about every flight.

So, kudos to you for endeavoring on this project… i’m keeping on aye/eye on this thread! Keep us posted! Love it when a flightsimmer dives deeper into matter…
Just yesterday i learnt about an addon for early 30’s mail routes in the USA… the flying mailmen of the day where flying through all kinds of rough weather visually following yellow lit arrows in the landscape every 10 miles.

Makes me kinda wonder if these letters on hills also have to do with those early routes in identifying cities… (here’s Kanab)

Woof ~ Woof & Salute!

Steiny

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Speaking of time tables, I dork out here quite often when looking for vintage routes to fly for the vintage airliners:

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Great work! Will be following. I am always interested in historical aviation infrastructure.

NDB navigation will be a little difficult in that charted magnetic courses have changed quite a bit as variation changes. VORs deal with this as well, but those were kind of set it and forget it, so even today the actual course of a radial doesn’t necessarily line up with a magnetic heading. As long as the 360 radial is calibrated geographically where it was at the time, it should work.

I’m working on a project in which I’m cataloguing all the NDB, VOR, and any interesting ILS/LOC-type approach in the US. I’m about 75-80% done, working west to east, and currently have analyzed annd documented around 130 NDB approaches.

SB (PETIS) and MOG (Montague) are the only two NDBs remaining in CA. There was a third, VFR only beacon in Corcoran not long ago, but it’s no longer charted. KSIY has the only remaining NDB approach in CA.

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The scenery will set the magnetic variation in MSFS to its 1950 equivalent, so the charted radials (as long as the VORs were properly aligned with magnetic north) and magnetic heading will be able to be flown also in MSFS.

Tested and it works :+1:

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That’s awesome. Now I’m thinking, “oh no, runway numbers…”

Yeah I know!

Just close your eyes on short final :laughing:

Nothing I could do about that :grimacing:

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I love the idea. I’m a big fan of vintage aircraft and navigation using the analog instruments, so I would fly this mod. I would think that it’s ok to publish a mod that removes modern navaids and adds alternate versions as long as it very clear to users how it will affect the sim and how to disable it when not being used.

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It is indeed, eh? :grinning: Sorry about that! I made it this way also to keep it as a to-do and a log for myself.

Alaska… if you happen to know about some historical charts, I’d be happy to hear about it :+1:

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I loved reading through all the ideas you were espousing!
Probably the oldest surviving thing I have related to what you want, probably isn’t old enough for your purposes. It’s a 1982 SkyPrints Aviation Enroute Atlas. Roughly an inch thick with lots of information about airports/routes/etc from that year. But I don’t know how much of the information is valid for any time before then. I had forgotten I even still had it (because so many things have been thrown out/destroyed in PCS moves, etc over the years) until your post. I forgot they even formally printed my name and (then) rank on the front! LOL
I just looked online and there’s a 1971 (my graduating class!) version available on ebay pretty cheap.
Regards

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In the US, there are is a lot of info about historical airspace, airways, and navaids in the Federal Register. It’s just not super easy to find.

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Interesting.

Do you know where to look? E.g. Alaska on the end of 1950s?

I tried but with no result :thinking:

The Federal Register is digitized and searchable from 1994 forward. Prior to that, it’ll be scanned archives, and not as easily searchable. Like I said, it’s not easy.

You might consider getting in touch with the National Archives and seeing if old aeronautical charts or supplement/FLIPs are available aside from the old sectionals they’ve already digitized.

It doesn’t look like they’ve digitized any of the old FLIPs, but I bet they have them. Here’s a page with a sample search and a bunch of contact information:

https://catalog.archives.gov/id/6921681

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Well, this might come handy if someone decides to go a similar rabbit hole as myself, only for 1980s jet liners (MD-80 or A-310) :slight_smile:

Does it include a list of navaids with lat / lon coordinates? Don’t worry if you don’t have time, just in case you remember…

Unfortunately, the Sky Prints don’t have the navaid data Lat/Lon information for each site (at least not on these older charts). It’s very much like the current enroute high altitude charts. It’s got 26 regional charts in total that cover the entire lower 48 U.S. states. While it shows all the VORs with frequencies, and the routes between them, it basically just shows the relative site of each VOR without specific information on their exact locations.
Sorry!
Regards

1 Like