@Art-Deco
Could someone here explain why the 3rd ADS-C attempt 2:01 didnīt give a GPS-position, and why BEA has removed all 3 attempts from the ACARS-list?
Clearly the 02:01Z was via ACARS as they were out of VHF-range.
1.. They are not ACARS messages. Those ACARS messages were transmitted via SATCOM to Air France Operations/Maintenance. The crew also rec'd METAR / TAF info ex Paris by the same means.
2.. The ADS-CPDLC uses SATCOM also, but the initial contact with an ATS is made by the crew. Once log on is established the ATC select the info they require etc..
Here are DAKAR's requirements to establish ADS-CPDLC:-
Connection procedure in the DAKAR FIR (DAKAR land and DAKAR ocean)
The first connection with the system is made by the crew. For flights entering the DAKAR control region from an FIR not equipped with CPDLC, the DAKAR control centre demands the connection at least twenty minutes before entry into the DAKAR FIR. For flights from a FIR equipped with CPDLC, the first connection must occur five minutes before entry into the DAKAR FIR.
NOTE: AF447 was not ADS-CPDLC with Brazil ATC and the 20 minute Log On requirement was in effect.
It is obvious that DAKAR ATC failed to make provision in their ADS-C system for an a/c they had accepted on a Virtual Flight Plan - hence the Log On failures. The interaction between ATLANTICO and DAKAR (or lack of it) may ultimately have a significant bearing on where the finger points.
mm43