A replacement for ACARS?
Jim, ACARS has noting to do with things like this (nice site) can do. So I do not understand what you mean with replacing this for ACARS.
BTW and again: this site does not give any information about ICAO-flight id's as far as I can see. Also not a, where in this days many many flight id's are in the "ICAO-language", usefull tool I think...
In my opinion
this one is much better. (Unfortunately out of order this day until sofar.)
Thank you anyway for your tip!