CDF/USFS Aircraft on 169.7000

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WayneH

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For quite some time some friends and I have been hearing short blurbs on 169.7000 that's always come from aircraft. Eventually we came to the conclusion it was aircraft supporting fire suppression and today I heard it very quickly with mention of GPS coordinates and then a friend later heard "air attack". (no doubt it was all related to the SC fire)

Anyone have any insight? I would guess it's a discrete USFS air channel or something. And no, no image of any sort, it's definitely 169.7000.
 

Lt51506

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I think this is a linked freq to NIFC. It's been a few years for me, but I know USFS uses a linked repeater sys nationwide that ties direct to the NIFC here in Boise....simular to the old VHF to Microwave CalFire had years ago. I'll ask next time I step into NIFC to be sure.
 

SCPD

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Lt51506 said:
I think this is a linked freq to NIFC. It's been a few years for me, but I know USFS uses a linked repeater sys nationwide that ties direct to the NIFC here in Boise....simular to the old VHF to Microwave CalFire had years ago. I'll ask next time I step into NIFC to be sure.
Boy Lt, you sure dropped a bombshell there. A nationwide linked repeater system direct to NIFC?!!! I've never heard of such a thing or any rumors to that effect either. You were in the business and should know, so I'm not doubting you. Not every Forest Service dispatch center has a National Flight Following (168.650) remote base installed nearly 10 years after the decision to use the frequency in that manner, so a nationwide linked system is quite a leap. I had access to official frequency directories until 2005 and there is no mention of such a network in Forest Service Regions 1, 2 , 3, and 5 directories. Please check that out at NIFC, now that you are close by!

Wayne, I just took a look through my ancient copy of Bob Grove's Federal Frequency Directory of 1980. It shows 169.700 allocated to the Department of Interior for nationwide use. Uses at specific locations, as almost every frequency has, are not listed. There are very few federal frequencies with nationwide clearance, at least in civilian agencies. I just took a look at a couple of threads I made copies of where people were reporting long lists of frequencies they were hearing on some of last fall's big fires. No one mentioned 169.700. I just happen to have some room in my new PSR-600's (room - imagine that) for this frequency and will have to monitor.

You heard it first on RR once again!
 

Lt51506

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What I was refferring to was a comm link on the admin net. Didn't have anything to do with flight following. Just a link to pass information. I'm not sure about the bombshell application...maybe a bottle rocket. I do remember clearly in 1981, sitting in the tower at Ryan AAB, and listening to one of the USFS people exchanging order numbers with SouthZone dispatch. When they were finished, I asked where their info was sent to. I was to it goes to Idaho and normally they'd do it from there, but the microwave was down. I never gave it any thought after that.

At that time, just about every CDF facility could key a mike and talk directly with Sacremento via microwave...thus I figured it was the same type or simular system. The radio system in my tanker had the capability of two cans and a string, so it's very possible I may be way off base here. I wasn't a radio enthuist back then and have not honestly given much thought to the old systems we had, all I knew was that I didn't care for them very much.

I know the new systems are quite a piece of work and have capabilities we only dreamed of back then. So, if I misguided anyone, please accept my apology. I was just referencing from memory.
 

WayneH

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I would definitely call this freq "discrete" based on its use. All comms have been between aircraft usually leaving or enroute an incident. Comms haven't been very chatty and have been semi-formal.

Thanks Exsmokey. It's info that gets us a little closer.
 

WayneH

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Activity on the freq has always been short and random as I'd guess them to be at high altitude and pass over quick. So you'll be lucky if you hear anything soon.
 

SCPD

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Lt51506 said:
What I was refferring to was a comm link on the admin net. Didn't have anything to do with flight following. Just a link to pass information. I'm not sure about the bombshell application...maybe a bottle rocket. I do remember clearly in 1981, sitting in the tower at Ryan AAB, and listening to one of the USFS people exchanging order numbers with South Zone dispatch. When they were finished, I asked where their info was sent to. I was to it goes to Idaho and normally they'd do it from there, but the microwave was down. I never gave it any thought after that.

At that time, just about every CDF facility could key a mike and talk directly with Sacremento via microwave...thus I figured it was the same type or simular system. The radio system in my tanker had the capability of two cans and a string, so it's very possible I may be way off base here. I wasn't a radio enthuist back then and have not honestly given much thought to the old systems we had, all I knew was that I didn't care for them very much.

I know the new systems are quite a piece of work and have capabilities we only dreamed of back then. So, if I misguided anyone, please accept my apology. I was just referencing from memory.
The Forest Service system you are referring to is made up of UHF and VHF frequencies and is known as the "South Zone Net." The two main hubs on this system are at Frazier and Santiago. Unless something has changed recently almost all of it is linked without microwave. The one exception I know of is the dispatch center for the Inyo National Forest and the Bishop Field Office of the BLM. They had a lot of trouble on the Cerro Gordo Peak (NE side of Owens Dry Lake) to Frazier path so they have hitched a ride on the state's microwave.

There is a North Ops network also and it uses low band frequencies and perhaps a VHF-High in a place or two. I don't remember right now. The hub of this system is at Saint John Mountain, just north of Clear Lake.

It should be noted that these two nets are only used to connect Forest Service, Park Service, and CDF dispatch centers. It is a dispatcher's intercom and field units don't use it.

As far as I know orders from each Geographical Area Coordinating Center (GACC) are forwarded to NIFC via phone or computer. In 1981 this would have been by phone as computer linking was not available then. My impression is that now, most of this information exchange is done by computer as there are software programs developed for tracking orders and resources that are a huge improvement over the old voice method. From what I have heard this has reduced the amount of traffic on California's two GACC nets. The Forest Service did not begin implementing the FLIP system (Forest Level Information Processing or "DG" for Date General) until 1984 and it was not completed nationwide until 1986 or 1987. That is why you heard order numbers being discussed on the South Zone net in 1981.

The only two Region wide systems I've ever heard of was the Pacific Southwest Region's Travel Net and the Intermountain Region's Calling Channel. As you might know, the Pacific Southwest Region (R5) of the USFS lost their travel net system to Homeland Security. I've been told that the Regional Calling Channel in the Intermountain Region (R4) has been removed from all the mountain tops. These are the only regional type systems I've ever heard of as man of the other Geographical Areas list 168.350 as a simplex travel channel.

Not all National Forests are using microwave to link their Forest Net systems for various reasons, one being that many of their sites don't have commercial power. When I was in the Southwestern Region of the Forest Service 1973-1981, construction on a Region wide microwave system, that would be used to link repeaters on each Forest and Forest to Forest, began. I don't know if they completed it as I transferred out of that region just as the first National Forest, the Cibola, installed theirs. They expected to complete one Forest per year for about 10 years and with 11 Forests in the Region, would have had the ability to send voice and data traffic all around the Region. When the long distance phone carriers got word of this they protested and the word at the time of my transfer was that we would not be able to carry our long distance phone communications on this network, in spite of huge savings to the federal government. The capability to add sufficient microwave channels to the system to carry all the telephone long distance traffic between Forest Service offices was going to be minimal in cost, something like 10% or less, and would have been quickly recouped, but apparently Congress had made a deal with the long distance carriers some years prior that most agency personnel had never heard of.

In California some of the Forests use microwave to link their repeaters, but not all. As far as I know the systems of each Forest are not linked. I've heard that some Forests are removing microwave and going back to 400 MHz links due to the high cost of powering and maintaining microwave sites.

As for the State of California, they have an extensive microwave backbone system and many different systems can be controlled by centralized dispatch centers, agency Sacramento headquarters, and the OES op center near Sacramento. I've never heard CDF repeaters being used by Sacramento here in the eastern Sierra, but then CDF traffic here is very light. Locally, I've heard OES, Caltrans, State Parks, and Fish and Game repeaters being used by OES Sacramento (now at Mather), Caltrans Sacramento, and of course, State Parks and Fish and Game being dispatched by "Northern" in Rancho Cordova. I know that at one time, the state had a long distance phone system for state agencies on their microwave, and commonly called it the "green phone." I don't know what the current status of this system is.

If I've missed a radio/microwave network that wildland fire agencies use, someone please step in and let us know.
 

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Lt51506 said:
You have probably seen this or have it in your records, but thought I'd send it anyway. I'll run over to NIFC next week and see what I can dig up.

http://www.nifc.gov/policies/red_book/2008/Ch15Comm.pdf
I hadn't seen it in that format, but I did have the same information from another source, that being the Forest Service on-line manual and handbook system, which contains most of their policy and direction.

But still go to NIFC and see what you can find out about anything we might be remotely interested in. I haven't been there since February of 1985 for a training course. When I went into dispatch they were busy dispatching resources to Costa Rica in response to a request made by them through the State Department. As a result I did not get the full tour they had promised us in the training course pre-work material. I'd love to go back and invite myself in there while they are not busy.
 

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The link Lt provided contains some text that can shed light on the use of 169.700 in an indirect fashion. First it says:

Radio Frequency Management
•
FM frequency assignments for normal operations or initial attack ground operations are made on a permanent basis and are requested through the state office ISO frequency manager to the Washington Office frequency manager.
This says that the National Incident Radio Support Cache frequencies that we all know about are to be the only ones listed for "normal" operations.

Then:

Frequencies for Type 1 and Type 2 incidents are assigned through the National Interagency Incident Communications Division (NIICD) located at NIFC. The CDO is responsible for this function.
This means that on large fires assignment of the Support Cache frequencies is made by the Communications Duty Officer (CDO) at NIFC. This is to reduce potential interference between incidents that might be nearby. This is for the permanent frequencies in the Support Cache. An incident does not just start operating on whatever normal frequencies suit them at the time, they must go through this process.

And finally:

During severe situations and/or when there are significant numbers of large incidents, additional frequencies can be assigned. These are temporary assignments, and are requested by the NIFC CDO from the Washington Office (Spectrum) managers and given by the CDO to the incident. This applies to frequencies for command, ground tactical, and aviation operations.

Additional frequencies are provided in the following circumstances:

The NIICD national frequencies are all committed within a specific geographic area.

The requests continue for frequencies to support new incidents within a specific complex.

The fire danger rating is extreme and the potential for additional new incidents is high.
Here is the understanding I gain from this. 169.700 is a temporary assignment. The temporary assignment frequencies might vary from year to year. A frequency might be used for air to ground on one incident and then be used for tactical purposes on another. People have posted that they have heard various frequencies being called "Tac 8" and "Command 9" and such. I don't think there are permanent assignments for anything above 7 for the command, tac, and logistics frequencies and for air to air or air to ground FM. I think with the advent of much larger incidents that we have seen in the last 10-15 years, combined with the availability of more frequencies available due to narrow banding, we are seeing some unfamiliar frequencies pop up on incidents. So I don't believe that some secret squirrel frequency list exists that shows "Tac 8", "Tac 9", "Command 11" etc. and up, that is being kept confidential.

The fact that the Summit Fire was the only fire of the type listed in the criteria above that was active at the time makes the use of 169.700 a mystery. Why make a temporary assignment when the use of the normal frequencies would not have resulted in interference to another incident?

Lt, if you can poke around a bit at NIFC if you can and see if you can ask about these new frequencies in use people have posted about. Is there a permanent assignment for additional tacs, commands, logistics, and air FM frequencies or not? You could ask the question in a manner where the discussion of specific frequencies is not brought up. Maybe they will be willing to share if it is put that way. Of course, if you can discuss specific frequencies, so much the better.
 

Lt51506

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NIFC was a wasted trip thismorning. Seem alot are still out on extra holiday time. I'll try again later this week.
I shot the question at hand out to a few pilots on my xmas card list. One (USFS) is guessing that it was an off-freq comm, but is going to ask around. Another (CalFire) sent me the 2008 updated Firescope freq chart. I'll keep digging for now.

http://www.firescope.org/ics-big-fog/ICS420-1AppendixA.pdf
 

Big_Ears

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Monitored 169.7000 on saturday and some on monday. No activity heard at SF Bay Area.
 

WayneH

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They were active today around 3:30 PM. I only heard one air unit talking about 25 gallons something-er-other (fuel or retardant?). Traffic went out of range a minute later.
 
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