Thanks for the link. Very helpful.
So basically a core network will remain and all replacements planned wont be complete until 2030, in the USA anyway in which case, considering my age, I might just not care anymore 
Any decommissioned will be replaced by a GPS station.
No clear explanation about TACAN which will provide in any case DME info but no bearing. However that need not be an issue. If it does both it is a VORTAC I am told.
So the good news is that we will be able to continue VOR navigation for some time yet.
GPS is getting a bad rap here. Itâs more correct to say that it is flight management computers with area navigation capabilities (RNAV) that has made things significantly easier. An A320 does not need GPS to display a nice green line on the map, it can calculate a position using the IRS with position updating from ground based aids. This tech was in use long before GPS ever hit the scene.
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You know why they teach pilotage and dead reckoning in every flight school around the world!!! Even if these vors are decommissioned, the principles remain the same, you will still be dealing with GPS intersection points serving the same goals as the existing Vor system.
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The tech behind GPS is amazing and we thank America for making it available to everyone.
It is the IRS that also blows my mind. Here is a totally self contained system using laser beams to detect motion and position. All it needs is a precise start-point coordinates (alignment).
It should be kept in mind that all gyro (mechanical or laser)/accelerometer navigation systems have a drift, i.e. an error due to the inability to measure accelerations to infinite accuracy, that increases over time. Basically all modern inertial systems use GPS fixes to update the inertial position at regular intervals to try to keep the navigation solution as accurate as possible. This sort of gives the best of both worlds, as the inertial navigation system updates much faster than GPS.
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Although we all keep referring to the 'decommissioning â of the VOR transmitters, in some ways that is misleading. They are actually being replaced by GPS stations. So yes, they will continue to exist as a point of navigation reference.
I think we are all using GPS as a kind of shorthand for the whole combined guidance system. But strictly speaking you are correct. For example I prefer not to use the complete guidance GPS systems yet use Auto Pilot sometimes in APPROACH mode.
You know⊠is it not fun learning to navigate with VOR? I find it a blast.
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What is not fun?
I find it interesting to be able to determine where your plane is and which direction to go in order to go to where you want to go to.
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They donât need GPS to update, DME / DME is very accurate.
You mean theyâre being replaced by a waypoint? Yes some are. The beauty of GPS though, is that you arenât restricted by geography when you create airways and waypoints. There may be times where an old VOR is replaced by an RNAV airway intersection but the designers are also free to completely scrap that position and airway and create something new that is more efficient.
Itâs sometimes difficult to have these conversations because naming conventions arenât consistent. What do you mean by APPROACH mode for example? In an Airbus A320 you activate the Approach Phase in the MCDU and this drives the target speed towards Vapp, the final approach speed. You can also arm the approach by pushing the APPR button. If flying an ILS this will arm the localiser and glide-slope, if flying an RNAV approach it will engage the Approach Navigation mode (APP NAV) and arm the Final Descent mode (FINAL in blue on the PFD). When reaching the Final Descent Point FINAL APP will become the active mode, this is a combined lateral and vertical mode that provides guidance to the runway. On a Garmin equipped plane there is presumably different terminology, Iâve never flown one so I donât know.
So itâs good to talk about the approach type itself, ILS, GLS, RNP, etc, and whether youâre using vertical guidance or not, autopilot on or off etc. These days a GLS approach, which uses GPS or similar with a ground based station to provide additional accuracy, is indistinguishable from an ILS in terms of how you fly it and what it looks like on the PFD.
Yes, I was only commenting on what the actual policy is.
I found this reference on a real world piloting website;
âIn 2012, the FAA released a proposed rule for a gradual reduction in the number of VORs in the National Airspace System. Citing the increased costs of maintaining a network of 967 VORs, the agency proposed cutting the number to about 500 VORs located at what the FAA calls the Core 30 airports around the country. Core 30 being the larger airports served primarily by Air Carriers. This level is called the Minimum Operational Network (MON).
The MON will provide:
A backup capability for lower end GA IFR aircraft in the event of a widespread GPS outage
An operational contingency, and not the robust network of current VORs
A transitional network of VORs to allow users time to equip with new avionics to transition to RNAV and RNP
Once the VOR system has reached the minimum operational network (MON), the planned VOR coverage would also enable airplanes in the conterminous United States to proceed safely to a destination with a GPS-independent approach within 100 nm. MON coverage would only be guaranteed above 5,000 feet AGL.
When a VOR is decommissioned, it is replaced with a GPS based intersection and GPS based airways. For most of us, the effect will be minimal. Only the rare GA aircraft that is still navigating solely by VORs will see an impactâand that is still years away."
Here a further official explanation of the proposed MON.
Significant is to note that the real World administrators certainly anticipate the possibility of a plane losing GPS functionality and pilots having to fall back on VOR navigation. So VOR is and will remain the bed rock of air navigation.
Concept of Operation
The VOR MON is designed to enable aircraft, having lost GPS service, to revert to conventional navigation procedures. This will allow users to continue through the outage area using VOR station-to-station navigation or to proceed to a MON airport where an Instrument Landing System (ILS), Localizer (LOC) or VOR approach procedure can be flown without the necessity of GPS, Distance Measuring Equipment (DME), Automatic Direction Finder (ADF), or surveillance. Any airport with a suitable instrument approach may be used for landing, but the VOR MON assures that at least one airport will be within 100 Nautical Miles (NM).
In order to enable VOR station-to-station navigation, two new geometrically larger VOR Standard Service Volumes (SSVs) are being implemented to provide VOR signal starting at 5,000 feet Above Ground Level (AGL). Coverage will exist but may not be continuous at lower altitudes.
For more details on how to use the VOR MON, please visit the Aeronautical Information Manual (AIM), Chapter 1. Air Navigation, Section 1-1-3-f, The VOR Minimum Operational Network (MON).
As I quoted from the professional pilot workshops site;
âWhen a VOR is decommissioned, it is replaced with a GPS based intersection and GPS based airways. For most of us, the effect will be minimal. Only the rare GA aircraft that is still navigating solely by VORs will see an impactâand that is still years away.â
I mean the point was that you need some kind of external position reference to correct the drift; GPS is just likely the most frequently used, especially if youâre doing blue water ops where thereâs no DME in range.
Iâm a big fan of GPS and glass cockpit systems.
Decades ago, I learned simming with a controller friend of mine, flying the B747 using VORs. That was fun and all, but it took quite some energy to fly 1000km.
Today I pop up Simbrief, load my flightplan into my FMS, set my SID and STAR and voilĂ .
I certainly donât criticize simmers who like good old times navigation (because why not?), and Iâm not by any means pretending that flying is just about pressing one button to go.
But then one can certainly see a nice evolution in today systems.
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Some people make out VOR nav to be some really exciting thing to do while flying, but itâs just setting a frequency and a course⊠Itâs cool, but you could also, in theory, program your route into the GPS as you go too, if you really want something to do with your time. Personally, I prefer to map a VFR route using landmarks, and then hand fly the whole thing. Then you really are doing something the whole time 
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I get the love for VOR. Itâs old-school and prone to a lot of limitations and errors that have to be overcome to use correctly. It only existed in certain locations, so you had to carefully plan the flight.
GPS reduces a lot of the guesswork. Itâs far easier and safer as long as itâs operational on both ends. Less work = less of the romance of navigating the aircraft.
Agreed. This is not about one being better than the other. Neither should this be a discussion about the desirability of GPS in the real world. We should all be grateful that in the real World, GPS exists.
This is about flying in the simulator. Some of us dont like complete GPS flying because we find it boring. Others enjoy the simulation of the real world GPS environment. All good. However VOR navigation has received little attention on this forum, but now it has had a good airing.
As to your example that one can simply enter route points in the GPS while flying this being similar to VOR, I would simply point out one issue with that;
Fly GPS, then the GPS keeps you on course. Fly VOR the pilot has to ensure you stay on course. (Yes I know you can set the auto pilot to track the NAV but you dont have to). So for some, that is more of an enjoyable activity. Some of us find it more thrilling to fly and arrive at the correct localizer and glideslope not because a computer has done that but because we have navigated the plane and got it right.
But this isnt a discussion about what is better.
At least in this thread we have discussed VOR navigation well, and who knows maybe inspired some folks who never considered it to have a look at it.
It is just a other way of enjoying the SIM.
I mean you could also hand fly the GPS route. Whether you follow the VOR or GPS with AP NAV mode is up to you. In fact, you can even use a course deviation indicator with GPS much like you would with a VOR course - you donât need to use a map.
Anyway, I do get the attraction of both. For example you could use 2 VORs to triangulate a destination that doesnât have a VOR on top of it. Ironically though, this probably works best in a glass cockpit as few planes have 2 VOR steam gauges.
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