How to add a TACAN to Tbilisi ?

[felafe]

Hello to all ,

 

my name is Felix and I´m from Germany to please excuse me for my english .

 

I switched over from FS2004 to DCS A-10C and i also wanna fly TACAN departures and approaches on DCS A-10C to do it as real as it get´s .

 

I got some charts of Tbilisi and they have a DVOR on frequency 113.7 (TCN 84X) and this one is needed to fly the SID`S and STAR`S .

 

Is there a way to add that TACAN manually ore with a script in the missionplaner ?

 

Hope for some help

 

Best regards

Felix

[LostOblivion]

Do not think this is possible without a mod.

[effte]

Are you positive that it is indeed a combined TACAN and VOR? A TACAN and a VOR are different navaids. They share the DME part though, which means a VOR/DME frequently lists the frequency in the "84X" format as well.

 

Cheers,

Fred

[Headspace]

There are combination TACANs and VORs called VORTACs but a TACAN equipped aircraft cannot use VOR and vice versa. The difference is that VOR incorporates a positive to/from flag and TACAN does not.

[hassata]

This may be of interest.

 

http://files.digitalcombatsimulator.com/en/38356/

[effte]

The difference is that VOR incorporates a positive to/from flag and TACAN does not.

 

The directional part of a TACAN operates on a completely different principle from the directional part of a VOR. Same function, but the similarity pretty much ends there.

[BlueRidgeDx]

A DVOR is nothing more than an "improved" VOR. DVOR's have slightly better accuracy, and are better suited for areas with significant terrain or man-made obstructions to the emitter.

 

The DVOR "rotates" the beam electronically instead of mechanically as in a regular VOR, and the frequencies are manipulated differently (AM vs. FM).

 

Otherwise, the difference is transparent to the user (pilot). It's just another VOR, and the "TACAN" channel listed in the Tbilisi approach plates is simply the DME channel.

[effte]

So what's the difference between a traditional VOR and a DVOR? Just better technology same function?

 

You have two signals, one amplitude modulated (AM) and one frequency modulated (FM) at 30 Hz. One is the reference and is the same phase in every direction, while the other varies phase depending on your direction from the facility. They are the same phase when due north (magnetic north) of the facility. When due south, they are phase shifted 180 degrees from each other.

 

The direction is sensed by the aircraft receiver through comparing the phase of the reference signal with the phase of the shifting signal.

 

Initially, a rotating antenna AM modulated one signal with direction dependent phasing while the FM phase was the same in every direction.

 

In a Doppler VOR, you rotate the transmitting antenna electronically through switching the signal between a number of antennas arranged in a circle, thus creating FM through doppler shift. The AM signal becomes the reference, while the FM phase varies with direction. As the aircraft receiver only cares about the relative phase of the two signals, it doesn't know the difference. Of course the FM signal phase change with direction change has to be the opposite of the AM signal phase change in a conventional VOR (CVOR).

 

The DVOR is far less susceptible to distorted signals, which is why CVORs are becoming pretty rare these days.

 

I'll probably explain this better after a night's sleep and morning coffee. :)

 

Cheers,

Fred

[Headspace]

Fred:

 

How would one distinguish between a DVOR and a CVOR on a sectional chart?

[effte]

Around here, it is stated in the charts. That's not the case all over though, AFAIK. For example, I don't think they distinguish between CVOR and DVOR in US sectionals.

 

Technically, both variations (and subvariations - there are quite a few!) must both adhere to the same standards so you really do not need to know the difference to use them. In actual reality, a DVOR typically performs better than the standards to such a degree that the difference is clearly noticeable in the cockpit, and thus it is at least interesting to know as you will then know what to expect to see when using the facility.

 

If you want to find out, I suggest going to the Aeronautical Information Publication (AIP). In the enroute (ENR) section, there should be a listing of navaids where it probably states whether a given VOR is a CVOR or DVOR.

 

Cheers,

Fred

[Murf7413]

Around here, it is stated in the charts. That's not the case all over though, AFAIK. For example, I don't think they distinguish between CVOR and DVOR in US sectionals.

 

No, the difference is not distinguished on us en-route charts... SOME SID and STARS do, but it is pretty uncommon so far. The reason I got (from an FAA inspector) as to why they are not stated as such, was that it is because they function... signal wise... the same as a standard VOR signal. So why change the symbology....