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New CA Air to Ground frequencies for 2012

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SCPD

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Thanks for the head up. Winter (if we can call it that this year) is my time to program my radios and this gives me plenty of time to do so.
 

SCPD

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This is the second document I've seen where a due date in 2019 is applied to frequency use. I've heard from time to time that 2019 is also the date when 6.25 kHz spacing will supposedly be required. So many entities are having enough trouble meeting the 1/1/13 for 12.5 kHz spacing that I can't imagine trying to get everyone to replace radio systems within 6 years. The current situation for compliance could take up the majority of that 6 years.

Back to air to ground, the frequencies for them are labeled differently depending on what Geographic Area Coordination Center is involved. I recently found a document showing a standardized nomenclature in the Western and Eastern Great Basin, and Rocky Mountain GACCs. There are 38 air to ground frequencies and they are used all over this large area. The assignments, for example, may have the Color Country Interagency Comm Center in southern Utah with AG-14 for primary and AG-32 for secondary. The Richfield Interagency Comm Center north of it may have AG-36 for primary and AG-8 for secondary. This document stated that a nationwide allocation of air to ground frequencies with standard nomenclature was desired and that this one, covering 3 GACCs, was a start.
 
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This is the second document I've seen where a due date in 2019 is applied to frequency use. I've heard from time to time that 2019 is also the date when 6.25 kHz spacing will supposedly be required. So many entities are having enough trouble meeting the 1/1/13 for 12.5 kHz spacing that I can't imagine trying to get everyone to replace radio systems within 6 years. The current situation for compliance could take up the majority of that 6 years.

Back to air to ground, the frequencies for them are labeled differently depending on what Geographic Area Coordination Center is involved. I recently found a document showing a standardized nomenclature in the Western and Eastern Great Basin, and Rocky Mountain GACCs. There are 38 air to ground frequencies and they are used all over this large area. The assignments, for example, may have the Color Country Interagency Comm Center in southern Utah with AG-14 for primary and AG-32 for secondary. The Richfield Interagency Comm Center north of it may have AG-36 for primary and AG-8 for secondary. This document stated that a nationwide allocation of air to ground frequencies with standard nomenclature was desired and that this one, covering 3 GACCs, was a start.
Is there any info for western Colorado you can pass on?
 

K6CDO

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This is the second document I've seen where a due date in 2019 is applied to frequency use. I've heard from time to time that 2019 is also the date when 6.25 kHz spacing will supposedly be required. So many entities are having enough trouble meeting the 1/1/13 for 12.5 kHz spacing that I can't imagine trying to get everyone to replace radio systems within 6 years. The current situation for compliance could take up the majority of that 6 years.
As of yet, there is no FCC mandate for 6.25 channel spacing in bands other than the 700 MHz band (currently 1-1-2017, with petitions to extend that date to 2023). If there is a 2019 mandate for 6.25, it would be a NTIA mandate for Federal users, and, I agree with you that it will be difficult to meet, considering that there are still 25 kHz Federal operations on the air, 7 years after the 12.5 kHz 'transition date.'

Also, any 6.25 kHz operation would have to be digital (law of receiver physics). The issue I see here is this: since P25 Phase 2 is two conversations in a 12.5 kHz channel, unless one of the DMR variants were to be adopted as an open standard, there is no ubiquitous 6.25 kHz method for simplex tactical use.

There is still a lot that is unknown, and with (erroneous) the congressional vision that 'Public Safety Broadband using LTE will fix everything - tomorrow,' much shouting yet to be heard.

Don
 
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f40ph

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State / BLM air-ground

There are more air to ground freqs arent there? BLM? CalFire?
BLM falls under the "Federal" air-ground channels listed above.

CalFire still uses 151.2200 for initial attack air-ground with 151.2725 (also an air-air channel) as secondary (usually for extended attack incidents)
 

SCPD

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BLM air to ground went away last year, I think it was. CalFire still has theirs.

Mark
What indication do we have that the BLM air to ground frequencies are not assigned for use anymore? There were 4 of them assigned geographically in much the same manner as these new Forest Service frequencies.
 

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The current FIRESCOPE/CalEMA and CDF group 3 lineups for 2012 do not have any air to ground frequencies listed for BLM's exclusive use or labeled as BLM's.
There may be an internal federal agreement that BLM will be assigned a specific frequency that I am not aware of.
The new lineup has the new fed A/G freqs as well as Air Tactics 1,2&3 now being available for A/G use.
Bottom line is that there are plenty of air to ground channels available.
If there are still BLM air to ground frequencies, they aren't getting passed down to the state or local agencies.
 
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SCPD

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The current FIRESCOPE/CalEMA and CDF group 3 lineups for 2012 do not have any air to ground frequencies listed for BLM's exclusive use or labeled as BLM's.
There may be an internal federal agreement that BLM will be assigned a specific frequency that I am not aware of.
The new lineup has the new fed A/G freqs as well as Air Tactics 1,2&3 now being available for A/G use.
Bottom line is that there are plenty of air to ground channels available.
If there are still BLM air to ground frequencies, they aren't getting passed down to the state or local agencies.
Do you have the 2012 CDF Kenwood load? You have a very good point here. If the BLM frequencies don't show up in the load then they could be defunct. I will be getting some federal information in a month or two for use in 2012. The 2011 info showed the four BLM frequencies as assigned for use. The Forest Service was authorized to use them as a secondary to 170.0000. The 2011 Kenwood load may not have included them because CDF and local agencies did not have narrow-banding completed yet. In the meantime I'm keeping them in my scanner.

The lose of 170.0000 is not really a significant one. It picked a lot junk on it with my Forest Service radios (mobile and handheld) as I drove through towns. Gas pumps and retail cash registers seemed to like it too. The Inyo NF radio tech told me "it isn't a true frequency" and I said "huh?" He told me it wasn't a "true sine wave frequency." I think it would have to be assigned to 170.0125 above it or 169.9875 below it. I'm not enough of a ham radio geek to understand if the radio tech was correct.

ColoradoRedlands, I will try to start a thread in the federal forum listing all the air to ground frequency information I have. What I have is 2011 information cover the Pacific Northwest, Great Basin (East and West) and Rocky Mountains Geographic Area Coordination Centers (GACCs). It is likely that my source will go dry for 2012, but I' m keeping my feelers out for another source. I will try create the thread in the next couple months. I'm pretty busy right now. Yosemite and Sequoia-Kings have unique air to ground frequencies assigned to them. I'm wondering if the remaining parks are assigned these BLM air to ground frequencies as they are both agencies within the Department of the Interior.

Air to ground assignments in the west, excepting California, all have unique primary and secondary frequencies assigned to each communications center with minimal reuse within a GACC. Some centers now have "local flight following" FM frequencies available. It is interesting that in California primary and secondary air to grounds are just being assigned and if anyone needs local flight following frequencies it would be in this state where the occurrence of large fires is greater.
 
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zerg901

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Might it be a good idea to do all air to air traffic on AM, thereby freeing up a few more FM freqs for air to ground work? Does a/g traffic ever happen on 168.20 168.60 etc or on the forest nets? They dont seem to have a lot of FM a/g freqs in California. And they dont use PL IIRC.
 

SCPD

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Might it be a good idea to do all air to air traffic on AM, thereby freeing up a few more FM freqs for air to ground work? Does a/g traffic ever happen on 168.20 168.60 etc or on the forest nets? They dont seem to have a lot of FM a/g freqs in California. And they dont use PL IIRC.
When I started with the U.S. Forest Service in 1974 all air to ground traffic was on 168.625 which used to be called "air net." It was also used for air dispatch, flight following, air to air and even dispatcher-to-dispatcher between communication centers. The traffic of some the latter did not always involve aircraft. Example when I worked on the Kaibab National Forest in the 70's I heard traffic such as "Coconino, Kaibab, what azimuth does Turkey Butte (lookout) have on our new start near Sycamore Canyon." Often only fire management officers or an assistant FMO would have air net radios (yes a separate radio). The use of 168.625 is now restricted to air emergency and brief initial contact if contact on other frequencies cannot be made and it is called "Air Guard." In my working experience, which includes four states, four national forests, three Forest Service regions and firefighting in 5 additional states on a total of 108 fires air to ground has not been carried direct on forest, BLM district and NPS park nets. Tac nets have never been used for air to ground, again in my experience, with some exceptions. Air to ground on forest net direct would tie up the entire forest including dispatch for new initial attacks as well as the other functions that use forest net, i.e. law enforcement, recreation etc.

Air to ground communications are usually between the IC and one aircraft (be that one helo, one air tanker or the air attack plane) or a division supervisor or crew boss with one aircraft. The amount of traffic and specifics can tie up the frequency for quite awhile which would preclude the frequency's use by all the other ground pounders. This would immediately present a safety problem.

As for the use of FM versus AM. The use of AM frequencies is governed by the FAA, not NIFC. AM is reserved for aviation coordination related traffic. The number of air to air frequencies is limited, more so than available FM air to air. FM air to air traffic is for fire tactics and can be monitored (ground units cannot transmit) by ground pounders on handhelds and mobiles. It is difficult to explain the difference between aviation coordination and air tactics relative to a wildland fire. Listening to the air attack organization on a large fire is the most effective way to learn the difference. You really can't use a scanner feed to listen to this difference as you need to see what frequency is being used and be able to control the scanner's scan and manual functions.

The Forest Service in California used to use 170.0000 for all air to ground. The BLM used 167.950 for all their air to ground. The BLM used to use 168.550 as "air net." This wasn't a problem unless fires were close enough to each other to cause interference with other high elevation aircraft enough that each aircraft could not hear the ground units because of traffic from other aircraft. If a fire got large enough that the NIFC cache frequencies were used another unique air to ground frequency would be assigned. Before the advent of programmable radios only one air to ground frequency was available as radios with lots of channels and the crystals to place in them were too expensive for the agency to afford them.

Beginning July 1st this year 7 air to ground frequencies will be employed by the Forest Service in California and they have been assigned based on four geographical areas. Only one frequency will be duplicated between these areas with enough distance and geographical separation to avoid interference. The BLM has been using air to ground frequencies assigned on four geographical areas in California for 2-3 years now. Large National Parks with exclusive jurisdictions (no state or local agencies with jurisdiction) often have their own air to grounds as they may tie up those frequencies for quite some time for search and rescue, medical and other non-emergency functions whereas the use of other nationally assigned air to ground frequencies is primarily for fire.

Elsewhere in the country air to ground frequencies are assigned on a dispatch center area basis. It appears that a standard list with a standard naming convention is now in use. So for example a frequency such as 166.7625 is called AG23 and is called such no matter what Geographic Area Coordination Center it is used in. It may be assigned as the primary air to ground for the Puget Sound dispatch center in Washington and the Grand Junction dispatch center in Colorado, but will be called AG23 in both locations. There are about 60 of these, but the complete list of them is presently not available to me. I will be doing some digging for these later.

In California the area each dispatch center covers is small in comparison with the rest of the country so they are not assigned for each center. I guess they could be assigned the same way as the rest of the country in theory, but there are probably not enough available frequencies to do it this way. California has a large number of interagency centers and a large number of Cal Fire only centers due to the amount of land with a heavy fire occurrence not adjacent to National Forest, National Park and BLM land. By the way, currently Cal Fire has only two air to grounds, but this will probably change in the next few years as more narrowband frequencies are available. One of their current air to grounds has only been available for a couple of years and is a narrowband frequency so it has only been available for narrowband capable radios.

I hope this answers your questions.
 
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zerg901

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Exsmokey thanks alot for the information. Its good to get your historical perspective on the channel usage.

Let me try to makeup a quick overview of the radio channels used at a wildfire on federal land in California.

Forest Net / District Net / Park Net - initial dispatch and response

Fire Net - maybe for IC to dispatch - or for all initial units responding to a first alarm

Tac Net - on scene ground to ground comms - portables and mobiles only

Air To Ground - IC to "aircraft in charge" (my phrase)

Air to Air - FM - air tactics

Air to Air - AM - air tactics or air coordination - maybe mostly helicopters in practice

Air Guard - 168.625 - emergency messages - air to ground, or air to air, or air to dispatch

Smoke Jumpers - 168.55 (if applicable) - jump ship to ground

Service Net - coordination with USFS Engineering units or setting up fire camps?

Law Enforcement Net - coordination with USFS law enforcement officers

These are all channels used on the initial response in the first burning period (which IIRC is before sun up of the day following the day of initial dispatch)

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Flight Following - 168.65 - no fire related flights - point to point flights

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If more resources are sent to the fire, then probably some portable repeaters will be put in place - UHF portable repeaters ("Logistics") at the fire camp - VHF portable repeaters ("Command") (maybe "NIFC") at the fire scene - the initial air to air channel and the initial tac channel might be given up also

I am not sure when the Region 5 tac channels would go into use - maybe if there is a shortage of tac channels.
 

SCPD

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Exsmokey thanks alot for the information. Its good to get your historical perspective on the channel usage.

Fire Net - maybe for IC to dispatch - or for all initial units responding to a first alarm

Air To Ground - IC to "aircraft in charge" (my phrase)

Air to Air - AM - air tactics or air coordination - maybe mostly helicopters in practice

Service Net - coordination with USFS Engineering units or setting up fire camps?

If more resources are sent to the fire, then probably some portable repeaters will be put in place - UHF portable repeaters ("Logistics") at the fire camp - VHF portable repeaters ("Command") (maybe "NIFC") at the fire scene - the initial air to air channel and the initial tac channel might be given up also

I am not sure when the Region 5 tac channels would go into use - maybe if there is a shortage of tac channels.
Fire Net - maybe for IC to dispatch - or for all initial units responding to a first alarm

On some forests the fire net is for all fire and law enforcement resources for dispatch and other operational traffic. On some forests initial attack dispatching is done on forest net and the fire net is used for command of initial attack fires.

Air To Ground - IC to "aircraft in charge" (my phrase)

All ground units including crew bosses, engine captains, dozers, water tenders, smokejumpers and overhead personnel lower than the IC may use this to communicate with any aircraft, not just the one in charge (air attack supervisor).

Air to Air - AM - air tactics or air coordination - maybe mostly helicopters in practice

All aircraft, not just helicopters, use air to air AM frequencies, called "Victor" frequencies. Air tactics usually stay on the FM air to air frequencies.

Service Net - coordination with USFS Engineering units or setting up fire camps?

Engineering units have nothing to do with Service Net except on the Mendocino National Forest. The service net is used for the fire to communicate with dispatch so that the command channel or forest and fire nets are not tied up with non-emergency traffic. Traffic usually consists of resource ordering, fire status, communicating when initial attack fails and an incident management team is ordered, etc. With better cell phone coverage the use of services nets is dropping. On some forests it may be used for another command channel or to move all non-fire communications to.

If more resources are sent to the fire, then probably some portable repeaters will be put in place - UHF portable repeaters ("Logistics") at the fire camp - VHF portable repeaters ("Command") (maybe "NIFC") at the fire scene - the initial air to air channel and the initial tac channel might be given up also

If a fire moves past the initial attack phase then a Type III team may order NIFC cache components such as command repeaters, permission to use additional tacticals, but Type III (local) incident management teams usually use local radio resources. When a fire is large and complex enough for a Type I or Type II incident management team to take over a fire then those things always happen. "NIFC" is used to signify frequencies assigned to the "National Interagency Incident Radio Support Cache." Initial attack air to air (both AM and FM), air to ground and tacticals are predetermined according to geography or by agency unit (forest, park, district, refuge, reservation). When a fire continues and grows permission is requested for other "NIFC" frequencies so that the pre-determined frequencies are available for other initial attacks. UHF repeaters for in camp use are not employed often. A camp has to get fairly large to do so. Simplex camp net frequencies are available. UHF frequencies are used for linking command repeaters or to provide remote bases for AM Victor frequencies. There is a separate allocation of UHF frequencies in the NIFC cache.

I am not sure when the Region 5 tac channels would go into use - maybe if there is a shortage of tac channels.

Region 5 or California (NPS, BLM as well) has the highest fire workload in the country. At one time only three NIFC tacticals were available as the BLM's were to be used by Dept. of the Interior agencies only. That wasn't enough so R5 was allocated three more. Later the BLM and Forest Service tacs, commands and logistical frequencies were pooled into the NIFC cache resulting in more frequencies being available. NIFC frequencies are used after a GACC requests permission from NIFC to use them. I believe the two GACCs in California can use R5 Tacs 4-6 without NIFC permission. They are still needed due to the workload in California.

One frequency has not been discussed and that is the Project Net. This is a region wide assignment of one tactical frequency to be used for non fire suppression activity. All the functions of the USFS (recreation, wilderness, timber management, range conservationists) including daily fire management personnel use this as a tactical or unit to unit net. In the past when this frequency was not available people tended to use NIFC Tac 2 for this type of work. The NIFC frequencies are assigned for fire suppression activities only so another frequency was needed. Outside California this might be called the Work Net or Channel. In the Pacific Northwest each forest has a Work Net. Even with only one in California interference is minimal and use by several functions or adjacent forests is coordinated by those using it. Since non-emergency traffic is involved it is easy to do so and it presents no safety problems.

I hope this helps you reach a better understanding of wildland fire frequency use.
 

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Additional on the flight following frequency. Automatic flight following, once established, has reduced use of this frequency. Local flight following is usually conducted on forest, district or park nets. Sometimes it is moved over the flight following is the primary net is busy with other traffic, fire or non fire. Some dispatch centers outside California have been allocated a local flight following frequency to remove it from their primary net as a lot of traffic can be involved, which ties up the primary net, which needs to be reserved for dispatches, command and use by other functions.

On large incidents flight following is done by the incident management or air attack supervisor. On initial attacks the air attack supervisor usually advises dispatch when air tankers leave a forest to reload and return or stay on a forest that has a retardant reload base or air tanker base.
 
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