SITA Legacy ACARS frequency change

[ATCTech]

It appears that at least for the Ontario Canada (and seemingly the adjacent northeastern USA (OH/PA/NY bordering Canada)) that SITA has done a wholesale change of legacy ACARS from 136.850 to 131.725 MHz.

Industry Canada data shows SITA Canada licensed on 131.725 MHz coast to coast now.

SQ messages from the CYYZ ground station are receivable here as are SQ messages from CYHM (Hamilton, Ontario).

Traffic on 136.850 is virtually (but not quite) zero with all received data being from aircraft well into US airspace.

That leads me to believe that additional VDL service will appear between 136.500 and 137.0 in the not too distant future although there is no specific pending license data on the Industry Canada list yet.

Cheers!

Bob

 

[DaveNF2G]

Another source indicated that 131.725 is slated for VDL-2. Possibly a misinterpretation?

 

[ATCTech]

That's a question I can't offer an answer to Dave. The move of legacy ACARS away from the 136MHz region around here seems to follow the European model of VDL being above 136.5 with 25kHz guard bands between the active frequencies. It's not more than a couple of years ago there were 3 or 4 legacy channels active in the US northeast in that range, then ARINC moved everything down and now SITA has too so I'm guessing VDL will appear there before it does in the 128.9 to 131.975 area, but only time, a watchful eye and pending license data will tell.

Is there anything on 136.850 in your area now? I wasn't paying particular attention to the few downlinks I saw on 136.850 last night to notice position reports.

I've got a fairly busy company ops frequency at CYTZ on 136.875 here that I'm now checking to see if it's active or relocated. That will be another big clue.

Cheers!

Bob

 

[DaveNF2G]

I'm not at my tracking computer right now, but I believe that only one of the four 136 MHz ACARS channels is active in my area. Maybe 2. I'll take a peek at my logs later to verify. .975 is quite active with VDL-2.

Keeping VDL-2 in the upper band makes sense.

 

[ATCTech]

Just as a follow-up, 136.875 is still an active voice company ops frequency at CYTZ, heard it active moments after writing my last post.

As for 136.850, today I'm seeing 2 bizjets sending repetitive Q0 (Link test) messages which would indicate that their CMUs haven't been updated with new frequency tables for SITA. There's no commercial traffic what-so-ever in range to me.

And yes, 136.975 hums right along with VDL traffic here too.

Cheers!

Bob

 

[DaveNF2G]

All of the ACARS activity above 136 here is on 136.850 according to my logs.

JetBlue is using 131.725 over NY and MA.