Who knew?

Timbeck2

Timbeck2

Final Approach
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Timbeck2
There is a conversion for Tacan channels to VHF DME receivers? I didn't and although I suspect a lot of instrument rated folks do, this is for those like me who didn't.

Up to channel 59 you have to add 1063.
From channels 70 on you have to add 1053.

For example the channel at Davis Monthan AFB is 123. Add 1053 and you get 1176. Move the decimal over and you get 117.6.

I was bummed that I couldn't fly the ILS on my home airfield because of DME derived from the Tacan. It isn't listed as 117.6 in the flip but as 109.3 which doesn't work. Now with my newfound information, I can have the ILS to myself on the weekends and not have to compete with the airliners to one runway at Tucson International.
 
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The Airport/Facility Directory Legend portion of the Chart Supplement contains a table showing the frequency/channel parings.
 
I knew that back in my ATC days Tim, but forgot about it soon afterward. :dunno:
 
It's on the Enroute chart and in the A/FD. I wonder if they leave it off the Approach deliberately. I'd bet that the chart builders there are so use to building TACAN approaches that it just didn't cross their mind to include it on the ILS.

NUQ does it.
Here's an interesting one, NUW. DME and VOR is required. VOR is needed for the missed approach. DME is needed for the approach. But then ya need VOR for the Localizer also. You'd think they would put the paired frequency on the chart. Looks the the military just don't want to do it. Is there such a thing as a Localizer only receiver?
 
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luvflyin said:
It's on the Enroute chart and in the A/FD. I wonder if they leave it off the Approach deliberately. I'd bet that the chart builders there are so use to building TACAN approaches that it just didn't cross their mind to include it on the ILS.

NUQ does it.
Here's an interesting one, NUW. DME and VOR is required. VOR is needed for the missed approach. DME is needed for the approach. But then ya need VOR for the Localizer also. You'd think they would put the paired frequency on the chart. Looks the the military just don't want to do it. Is there such a thing as a Localizer only receiver?
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I don't know... Moffett has the paired frequency for the TACAN on the plate. I think it might have just been the builder of this approach got lazy
Moffett.jpg


In the KC-135, we had two VOR/LOC receiver, but we had to dial in the TAC channel to get the DME (only one TACAN receiver). So we always had to tune two radios for VOR/DME or LOC/DME and we'd brief it like that. You'd hear "we'll dial in the localizer 110.35 channel 123."

I also flew C-12s for a bit, and it was the opposite. The DME was linked to the VOR frequency, so in that airplane to get this Moffett approach done, we'd have to dial in 117.6 for the VOR associated with the Moffett TACAN, and go "DME hold" which would hold the DME channel, then we could tune the radio to 110.35 to have the localizer information displayed along with DME from NUQ.

If we had to fly that NUW approach in the C-12, we'd have to look up the paired frequency to hold the DME. And it'd be annoying. And we be complaining about the guy who published that plate. ;)
 
Sluggo63 said:
I don't know... Moffett has the paired frequency for the TACAN on the plate. I think it might have just been the builder of this approach got lazy.
Click to expand...

NUQ are FAA-built IFPs. DMA are USAF-built. Having said that, additional data such as frequencies are the responsibility of the chart making entity, not the procedure designer.
 
aterpster said:
NUQ are FAA-built IFPs. DMA are USAF-built. Having said that, additional data such as frequencies are the responsibility of the chart making entity, not the procedure designer.
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I know about the two different Procedure designers, because with military flying, knowing who designed the IFPs determined how we did our takeoff data calculations.

That is interesting about the additional data. So, I'm imagining a room full of chart makers in front of their computers taking the raw data from the IAP designers (whether US or Foreign) and building the plates in their own format. So one guy at one terminal can decide to add the paired VHF frequency to a TACAN data block, and the guy sitting next to him can omit it? I'm surprised there's not a standard.
 
Sluggo63 said:
I know about the two different Procedure designers, because with military flying, knowing who designed the IFPs determined how we did our takeoff data calculations.

That is interesting about the additional data. So, I'm imagining a room full of chart makers in front of their computers taking the raw data from the IAP designers (whether US or Foreign) and building the plates in their own format. So one guy at one terminal can decide to add the paired VHF frequency to a TACAN data block, and the guy sitting next to him can omit it? I'm surprised there's not a standard.
Click to expand...

Attached is the source document that the FAA, Jeppesen, LIDO, etc. would receive from the FAA for the Moffett ILS 32R. I don't have access to the USAF source for DMA, but it would be similar.

The U.S. is the only country that does it this way. Other countries place an actual chart in their AIP, which would have all airdrome data.
 

Attachments

  • CA_MOUNTAIN VIEW_ ILD32R_NUQ.pdf
    338.8 KB · Views: 7
I didn't mention that I also found it on the low en-route chart before I posted this. I used to be a terpster as well in the Air Force but they didn't teach that in terps school. And, I've never laid eyes on Jeppenson charts. Go figure right?
 
Always thought you looked like one of them terps! ;):D
 
aterpster said:
Attached is the source document that the FAA, Jeppesen, LIDO, etc. would receive from the FAA for the Moffett ILS 32R. I don't have access to the USAF source for DMA, but it would be similar.

The U.S. is the only country that does it this way. Other countries place an actual chart in their AIP, which would have all airdrome data.
Click to expand...
Wow. I've used host nation approaches before, and with a little study, you can usually decipher them. I can't believe this is what the FAA hands out. And I don't even see any frequencies listed on that source document. Do the plate builders have to go search that out themselves?
 
Sluggo63 said:
Wow. I've used host nation approaches before, and with a little study, you can usually decipher them. I can't believe this is what the FAA hands out. And I don't even see any frequencies listed on that source document. Do the plate builders have to go search that out themselves?
Click to expand...
Indeed they do.
 
Sluggo63 said:
maryland_terrapins.png
Click to expand...

There is a relationship. When the FAA instrument design experts were formulating TERPs as a replacement for 1956 criteria (TERPs became effective in November, 1967) some of them were Maryland fans. So, they decided on the acronym TERminal instrument ProcedureS to game the school. I've had it as a PLP since they came out in California in 1975. I've often been asked if I am from Maryland. Other times, people ask, "What does that stand for?" No one has ever mentioned its aviation meaning.
 
aterpster said:
Attached is the source document that the FAA, Jeppesen, LIDO, etc. would receive from the FAA for the Moffett ILS 32R. I don't have access to the USAF source for DMA, but it would be similar.

The U.S. is the only country that does it this way. Other countries place an actual chart in their AIP, which would have all airdrome data.
Click to expand...
Here's an intersting one, http://155.178.201.160/d-tpp/1704/00451ILD14.PDF. Looking around at other approaches it seems the Navy follows the Airforce logic to not put the paired frequency for TACANS on approach charts. It makes sense to a certain point. But when you have an approach that does not require TACAN to fly, then it doesn't.
 
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Sluggo63 said:
I know about the two different Procedure designers, because with military flying, knowing who designed the IFPs determined how we did our takeoff data calculations.

That is interesting about the additional data. So, I'm imagining a room full of chart makers in front of their computers taking the raw data from the IAP designers (whether US or Foreign) and building the plates in their own format. So one guy at one terminal can decide to add the paired VHF frequency to a TACAN data block, and the guy sitting next to him can omit it? I'm surprised there's not a standard.
Click to expand...
Yeah. On all kinds of charting discussions it sometimes seems that no one is in charge anymore.
 
My Associates Degree is from the University of Maryland. ;)

So yes, I'm one of those too.:p

But my Bachelor's is from Park University which is some sort of Pirate.
 
I would have thought your associate was from CCAF? Mine is, ATC.
 
Although I had the credits, I never pursued a CCAF degree as I didn't want to get laughed at by an employer.
 
If a BS is bull****
And a MS is more****
And a PhD is piled higher and deeper
then what is an AA or AS
I ain't criticizing no ones degrees, just funin a little
 
luvflyin said:
Here's an intersting one, http://155.178.201.160/d-tpp/1704/00451ILD14.PDF. Looking around at other approaches it seems the Navy follows the Airforce logic to not put the paired frequency for TACANS on approach charts. It makes sense to a certain point. But when you have an approach that does not require TACAN to fly, then it doesn't.
Click to expand...
TACAN FREQUENCY PAIRINGS ARE USUALLY ON PAGE J1 OF THE AERONAV/NACO TERPS BOOKS.
upload_2017-4-30_21-31-52.png
 
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