The purpose of this European Standard is to establish uniform requirements for design and development of software architecture for modular avionics systems as defined per ASAAC.1.1 Software Architecture OverviewThe ASAAC Software Architecture is based on a three-layer stack as shown by a simplified Figure 2.Each layer is described in terms of it dependency/independency on both the aircraft system and the underlying hardware.1.2 Software Architectural ComponentsFigure 3 provides an overview of the software architectural components and software interfaces.1.2.1 Functional ApplicationsThe term """"Functional Applications"""" relates to all functions that handl