This document contains the Minimum Aviation System Performance 
Standards (MASPS) for communications utilizing High Frequency 
Data Link systems for the air-ground communications sub-network 
in an Aeronautical Telecommunications Network (ATN) 
environment. The FANS 1/A data link environment is also 
addressed.  Where systems are global in nature, the system may 
have international applications that are taken into 
consideration. Compliance with these standards is recommended 
as one means of assuring that the system and each subsystem 
will perform its intended function(s) satisfactorily.