NoD
"Ummm, have you ever used HF? It's hard to enough to talk over, passing data I would think impossible. Just listen to the bandwidth of SELCAL for data transfer - maybe 1 or 2 chs /sec
AFAIK ACARS works over VHF (los) or Satcom (when VHF unavailable)."
HF ACARS is possible, works, and is still in use, I just received this message.
[MPDU 17:41:04 AIR CO1495 SLOT 4 300 BPS ]
Nr LPDUs = 1 Ground station ID SAN FRANCISCO - CALIFORNIA NOT SYNCHED
Aircraft ID AC
Slots Requested medium = 0 Low = 0
Max Bit rate 600 bps U(R) = 0 UR(R)vect = 0
[LPDU UNNUMBERED DATA FM AIR CO1495 TO GND]
[HFNPDU PERFORMANCE]
17:41:02 UTC Flight ID = CO1495 LAT 33 58 59 N LON 117 55 27 W
Performance version 138
Flight Leg 76
GS SAN FRANCISCO - CALIFORNIA
While ACARS is effective the tracking functions might be better served by a version of ADS-B
Automatic dependent surveillance-broadcast - Wikipedia, the free encyclopedia which brings as a side effect such sites as
http://www.flightradar24.com/
I was hoping some of the pilots here could comment on how/when HF ACARS is used as at least in my area it seems a minority of planes use it.