Capturing and Defining Interface Requirements in Commercial Aircraft Development Program

With the increasing customer expectations s and the development of civil aircraft design technology, the functions to be performed by the civil aircraft systems become more and more complex. Meanwhile, those functions will interact deeply with complex logical and physical manners to complete different missions indifferent operation scenarios. Used to describe the information, data, geometry constrains and logic between two interacting functions, interface requirements play an extremely important role in not only the aircraft architecture development process, but also the aircraft integration and verification process. Therefore, it is essential to capture and manage all the interfaces completely and properly to ensure the aircraft as well as the onboard systems to perform the expected functions under some certain operation scenarios. All onboard systems development terms will define their required and provided interface information according to the system architectures and characteristics concurrently. It is required to define an interface development process in order to take on the above challenge, which often results from ambiguous expression of interface requirements, and the difficulty in managing huge amount of data about interface requirements, and in the control frequent changes. Based on the generic aircraft development process, this paper proposes a systematic approach for capturing and defining interface requirements. The interface development and definition activities throughout the aircraft program life cycle are elaborated in details. The interface classifications and the corresponding interface types and examples are introduced. The interface topology relationship and data model is investigated and defined, which forms the basis for the interface linkage and interface management database development. A case study is carried out to demonstrate the interface requirements development approach proposed here. It is found that the structural interface development process is helpful for engineers to capture the interface together with relevant attributes, which are represented in a uniform and unambiguous format and therefore can serve as the basis for relevant stakeholders to understand the interface definition. A significant advantage of the proposed approach is that it allows systems engineers to arrange the huge amounts interface together with interface attributes according to the interface classifications and types. It also shows that the interface data topology architecture enables engineers to establish traceabilities between interface requirements, which is beneficial to change impact analysis and interface consistent check.