scope:

Communications supporting the Air Traffic Service (ATS) and Aeronautical Operational Control (AOC) may be provided by one or more satellite system, each of which has particular operating characteristics. Change 1 to DO-270 - Minimum Aviation System Performance Standards (MASPS) for the Aeronautical Mobile-Satellite (R) Service (AMS(R)S) as Used in Aeronautical Data Links provides a system specific description of the Iridium Satellite communication system configuration including Ground Sub-networks; Iridium Satellite Subnetworks, of which the Aircraft Earth Station (AES) is one part; and Aircraft Sub-networks. The minimum system performance standards in Change 1 address only the Satellite Sub-network.