60's ACARS
Shannon on HF fantastic especially when you have taken off from the middle of no where with no met info available. Even get it on the ground. METARS and TAFS. Almost as good as the old teleprinter on VC10's which was a sort of 60's technology ACARS. noisy so the skipper got really irritated when it started clanking away and woke him up at 20 West!