Update 29 May 2023: The FAA plans to allow GA/BA aircraft to use enroute CPDLC from Aug 31. At the moment, you can only use this if you’re already registered as part of the trial, as per KFDC Notam A0171/22, but from Aug 31 this will get rescinded and CPDLC should be available to everyone. Sounds like there might be green/yellow/red lists drawn up for aircraft depending on their avionics – but only “red” category aircraft (those with serious avionics issues) will be unable to use CPDLC. For more info, check here.
Below is the original story from 28 Mar 2023:
The US has recently implemented en-route CPDLC in more centers across the country. So now, for the first time ever, you can fly coast-to-coast using CPDLC.
And what’s more – KUSA is the one and only code you need.
Who is KUSA?
For those of you who aren’t so familiar with the US, KUSA is the CPDLC logon code.
You might know KUSA from getting your clearances. The US actually gives two types of departure clearance via KUSA – a DCL or a PDC. DCL is the one where you don’t have to read it back. PDC technically requires a voice read back (but in the US they don’t seem to).
If you are flying across the NAT then this clearance usually includes your entry clearance too – so you get this when you get your departure clearance.
KUSA is the one and only logon code you need, all the way across.
So do I need CPDLC now?
US domestic datalink is not mandated. In fact, they are not currently allowing any GA aircraft to use enroute CPDLC unless they are a part of the “US Domestic En Route CPDLC Avionics Trial”. And currently, they are also not allowing any new operators to join this trial!
You can check all that out here on the L3 Harris site. They have a whole load of information on there about DCL stuff too so definitely worth a look.
What if I’m flying into the US internationally?
To make us of US domestic enroute CPDLC, foreign operators must have FAA approval (J4 on their A003). L3Harris also need to have confirmed that your aircraft avionics configurations meet the compatibility requirements per the Recommended and Required Avionics Version List (RAV-E). If in doubt about any of this, contact them at DCIT@L3Harris.com for any eligibility questions.
For eligible aircraft inbound to the US, there are some differences in logon guidance depending on whether a CPDLC connection is already established from the previous data authority, and whether the aircraft is entering via active or non-active US domestic enroute airspace.
Ultimately, all the answers can be found here. This doc lists all the inbound/outbound scenarios, and how CPDLC will work in each situation.
That’s about it (for now)
The real news here is that the trials have extended across the US, and domestic CPDLC is growing!
More on the topic:
- More: Datalink in Europe: What Are The Rules?
- More: What we know about the US CPDLC trial
- More: NAT Conundrums Volume III: To GOTA and beyond!
- More: CPDLC Gotcha: Clearance Busts
- More: Europe CPDLC: The Mandate We Missed
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As of last week, hand-off between KUSA and Navcanada is not working in either direction.
At the hand-off, whatever connection in use is terminated and a manual login needs to be made to the next sector
Looks like the Recommended aircraft and avionics posted was for Commercial aircraft. There is a GA version on L3 site as info. Also thinking it would be a good idea to reference foreign operators needing to get on the CPDLC Enroute Trial list via L3 (which I believe is still on hold) in order to qualify to use enroute CPDLC in the US
PDC is delivered via ACARS (not via CPDLC using the KUSA logon).