A system architecture represents the logical and functional view of an aircraft system. It complements the physical and geometric description provided by genericSystems by defining the connections between instantiated components and their interfaces to other systems.

In accordance with the CPACS top-down approach, a system architecture may initially be specified only by its systemType. The systemType can be used to classify the architecture by a predefined ATA chapter or by the keyword generic.

The optional controlDevices can be used to describe operating states by assigning abstract control parameters. The optional connections define the source and target of interactions within the architecture. These references may point to components or sub-components, or alternatively to external elements (ambient | passengers), ATA chapters, or other system architectures.