ACARS Frequencies in db?

[b52hbuff]

The California DB ADmin is doing a great job of filling out the statewide aviation frequencies. I was curious to know if ACARS frequencies should be submitted to the database?

I did a search in this forum on ACARS and didn't see anything. I looked in the reference county and didn't see any ACARS frequencies.

ACARS uses a small pool of frequencies, but only a couple are used at each airport.

If you don't know about ACARS, here is more information:
ACARS - The RadioReference Wiki

 

[kma371]

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I don't think they are airport specific, just think TX locations are at the airports. Also,Since there are so few and it's data, I think a wiki entry might be more appropriate.

Just my two cents.

 

[ka3jjz]

They are neither airport specific nor transmitter location specific. They are company users, however, and it's a little tricky, since more than one company can use one or more of the ACARS channels.

Certainly a wiki article can be built for them - we have a start on one, just for the NE US here, which illustrates this point nicely...

ACARS Frequencies in the NE US - The RadioReference Wiki

73 Mike

 

[kma371]

They are neither airport specific nor transmitter location specific. They are company users, however, and it's a little tricky, since more than one company can use one or more of the ACARS channels.

Certainly a wiki article can be built for them - we have a start on one, just for the NE US here, which illustrates this point nicely...

ACARS Frequencies in the NE US - The RadioReference Wiki

73 Mike

does it have to be northeast us specific? can we start an entire US one instead?

 

[ka3jjz]

Sure why not? This was data gleaned from the NF2G website migration, so it focuses just on the NorthEast

73 Mike

 

[DaveNF2G]

The data from my old website is usable nationwide, at least as far as the frequencies go. There are now about 10 ACARS channels, some of which are above 136 MHz. I have seen U.S. and other carriers on the "Canada" channels, too. Might as well put the bare channel list into the Wiki at least.

For the HP-1, most users probably would not want to scan ACARS as there is no voice traffic there. Perhaps they can be tagged in the DB in such a way as to default to being avoided in HP1 scanlists.

EDIT: The way the geotagging is set up for the HP1, most of the ACARS channels listed on my website would not be scanned from my location, even though they are listed there because I have been intercepting traffic on them. caveat emptor

 

[ericcarlson]

I'm going to say that ACARS should not be in the database. My understanding is that these are effectively nationwide and we have this topic covered in the wiki. (If they were in the database the they would be tagged Data anyway and not scanned by the HP1.)

 

[LAflyer]

As someone that deals with airlines, yes in essence the frequencies are nationwide, and in many cases global.

There are two primary global ACARS providors - ARINC and SITA(Aircom) with several resellers of the services such as Honeywell.

ACARS datalink is possible via HF or VHF ground stations(several hundred in the US alone) or via SatCom, or a combination of all depending how the aircraft polling and software is setup.

I think having something in wiki would be easy enough and suffice instead of creating new entries for every US ground station, which are not always are at airports anyways but can be located on mountain tops, or other geographic locales to provide large area coverage.

 

[b52hbuff]

They are neither airport specific nor transmitter location specific. They are company users, however, and it's a little tricky, since more than one company can use one or more of the ACARS channels.

I'll go look through my SFO notes, but the licenses I remember were at airports. I got the frequencies by doing proximity searches at airports.

What I was thinking when I asked the question was to simply list the ACARS frequency as a generic channel, tagged as data.

So from the ACARS user (e.g. flightcrew) point of view, how do they use the frequency? Is it hard coded into their gear? Do they have a sheet for each airport they fly into?

p.s. Sometimes questions extend beyond the HP-1. But it is interesting to talk about hardware independence when GPS scanning is a Uniden patented feature.

 

[morfis]

The aircraft will be set to use a specific frequency (depending where it is and who the airline's service is provided by). Usually a list is set and the aircraft unit will use the second freq if it gets no response from the first etc. There is an uplink ACARS message type to force the unit to change frequency and another to to set a new list.

 

[LAflyer]

From crews point of view two things happen.

On many newer glass cockpit aircraft the frequencies programed to start with for the providers you use, and the the comm radio can switch around as the aircraft moves between regions. In addition as mentioned by morfis there is also sometimes an uplink message that tells the unit to switch frequencies.

Otherwise crews can tune frequency manually into the comm radio radio assigned to data as they move around as needed. However both ARINC and SITA/Aircom have pretty generic frequencies that work in large areas so its not like they need to retune every 15 minutes or something.

Additionally in some cases there are primary, and secondary frequencies most often in high density traffic areas and in the automated scenario the aircraft knows this and can poll and use whichever is least busy. I can add that airlines can designate a sequence logic for ACARS usage. For example first attempt to connect via VHF, then try HF(if equipped) and last SatCom(if equipped) for example.

 

[b52hbuff]

Ok, time for a little more research. Here is how I started to learn about ACARS locality:
FCC Callsign Proximity Search: N 37.61911 W -122.37525 Range: 0.1

AF licenses are the airline 'company' frequencies, managed by ASRI but used by the airlines.

Here is the specific license for ACARS frequencies:
FCC Callsign WCH73 Details

 

[Finto]

I think it's funny (and interesting nontheless) that people want to monitor ACARS. As an airline pilot, whenever I hear the "SELCAL" sound in the cockpit that means an ACARS message has been recieved, I cringe because it means Crew Scheduling is trying to mess with my schedule and might miss my commute home. Other than that i can't see how interesting it can be seeing that Flight XXXX has requested 3 wheelchairs when they get to Boston or that Flight XXXX is changing from gate B12 to A14. Maybe if I wasn't a pilot i would find it cool.......but for the time being I think if I had ACARS at my house too I would go insane.

 

[hfxChris]

I don't think people necessarily decode ACARS because they find the content exciting, they do it because just receiving and decoding it in and of itself is exciting.

 

[kma371]

Plus the position reports are nice when using programs like PlanePlotter