As one of the Shanwick voices, can I just say that on first contact a datalink enabled flight need only give us its 1) callsign 2) CPDLC, ADS or FMC 3) next oceanic/FIR or exit point.
Once we have your callsign we know exactly what your selcall code is (and any relevant position reports). So saying it takes up airtime needlessly. (In the rare instance where your flightplan hasn't automatically gone into our system we can always ask you for your selcall code.)
You don't need to give your position or your routing. The track letter (c) or the last two fixes (d) are only to let us know where you're going next, so we can give you the appropriate frequencies.
"Shanwick, Speedbird 245. CPDLC. Santa Maria next."
- it's concise, and it tells us exactly what we need.
"Shanwick, Speedbird 293 at Dogal, flight level 360 estimating 54 north 20 west at 1915 and gander is next. CPDLC. Alpha Hotel Delta Sierra"
- a lot longer and even though the information we need is in there, so is a lot that we don't need.
I hope this helps.
PS to answer Random's question directly, d) is talking about the last two points in your clearance. These are named pairs like Dogal Bexet, Etiki Reghi, Omoko Gunso, etc. and it would normally be worded like this
"Shanwick, Air France 007, CPDLC exiting Dinim Elsox"
Last edited by PIGDOG; 18th October 2011 at 23:20.