The Advanced FMCS provides expanded functions beyond that defined in ARINC 702 to support the anticipated requirements for operation in the CNS/ATM operating environment. GNSS and RNP based navigation, air-to-ground data link for communications and surveillance, and the associated crew interface control/display definitions are included. The NextGen/SESAR concepts and their relative effects on the FMS are addressed in this document. The functional requirements also apply to a Flight Management Function (FMF) in an Integrated Modular Avionics (IMA) architecture with software partitions.