ACARS
The airplanes installed with ACARS may have several functions:
1. The airplane installed with ACARS & activated FANS capability, this airplane is able to communicate ATC via ACARS (CPDLC function).
2. My company modifes ACARS software, let flight crews caculate V1/Vr/V2 via ACARS, and request & receive loadsheet, flight plan, send flight log etc..