Is HF still used for transatlantic crossing ?
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Is HF still used for transatlantic crossing ?
As i heard, CPDLC has become mandatory for atlantic crossing, if not you stay at or below FL285. If that is the case , commercial airliners do not use HF anymore on a regular base ?
Meaning that HF communication above the atlantic is facing extinction ?
Meaning that HF communication above the atlantic is facing extinction ?
HF required, SELCAL watch established on initial contact. Apart from that all position reporting/monitoring done automatically by CPDLC. All other comms eg climb request, VHF allocation on leaving NAT HLA, reroutes done by CPDLC. With good HF propagation I reckon you can get across the Atlantic with half a dozen sentences and a minute’s use of HF.
North Atlantic Ops and Airspace Manual Ch 6 refers.
North Atlantic Ops and Airspace Manual Ch 6 refers.
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Thx guys for reactions, any info how CPDLC works ? seems to work on VHF frequencies, but as its range is only line of sight, so halfway between europe and USA, distances are way to big for VHF, i ve read about satellite links (FANS frequencies), but uptill now only A380 and some B787 are equipped with the FANS satellite comm systems ?So how does CPDLC communicate over 1000 miles via CPDLC ?
Thx guys for reactions, any info how CPDLC works ? seems to work on VHF frequencies, but as its range is only line of sight, so halfway between europe and USA, distances are way to big for VHF, i ve read about satellite links (FANS frequencies), but uptill now only A380 and some B787 are equipped with the FANS satellite comm systems ?So how does CPDLC communicate over 1000 miles via CPDLC ?
I'm not up to speed on exactly where we are these days with the various iterations of FANS but I used CPDLC via satcom on the 777 for a decade plus and at least some if not all of our company 747s were retrofitted to allow the same capability.
Not sure if it has changed but last time I flew the pond earlier this year despite carrying and being logged in on CPDLC a check of HF entering each oceanic FIR was required (e.g. Shanwick to Gander at 30 west) and then maintaining a selcal watch on that frequency was still a requirement. Lack of CPDLC barred you from certain routes.
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So i can state that actually most CPDLC systems are equipped with both VHF and (or) satellite link, probably with automatic selection depending on gps position, thx guys !
For a slightly more accurate description:
CPDLC & ADS are both part of Datalink.
Datalink uses both Satcom & VHF
Both/either can be disabled (MH370?)
Think of ADS as the equivalent/alternative to Radar
ADS position reports are automatic
I think ATC can also interrogate ADS on demand?
Think of CPDLC as the equivalent/alternative to voice.
CPDLC position reports are sent manually, or can be ‘armed' to send conditionally
CPDLC is primary in NAT, when HF is voice backup
CPDLC may be secondary if you have VHF (BIRD)
CPDLC is primary Indian Oceanic
CPDLC is primary in Australia, until VHF coverage, then VHF/ADS (no position reports*)
Not sure where/how FMC position reporting fits in to this? Maybe aircraft specific?
CPDLC & ADS are both part of Datalink.
Datalink uses both Satcom & VHF
Both/either can be disabled (MH370?)
Think of ADS as the equivalent/alternative to Radar
ADS position reports are automatic
I think ATC can also interrogate ADS on demand?
Think of CPDLC as the equivalent/alternative to voice.
CPDLC position reports are sent manually, or can be ‘armed' to send conditionally
CPDLC is primary in NAT, when HF is voice backup
CPDLC may be secondary if you have VHF (BIRD)
CPDLC is primary Indian Oceanic
CPDLC is primary in Australia, until VHF coverage, then VHF/ADS (no position reports*)
Not sure where/how FMC position reporting fits in to this? Maybe aircraft specific?
