A Functional Requirements Development and Management Approach Applied to a Civil Aircraft Program

Abstract

The functions and requirements play an extremely important role in developing complex systems, providing a framework so that all engineers involved in a project have a common understanding of the scope and characterization of the system. Meanwhile, the functions and requirements are used to specify the system itself, as well as relevant auxiliary products and services which the stakeholders expect and desire. In this paper, a functional requirements development and management approach applied in a civil aircraft program is introduced. The operational scenario/use case definition, functional analysis, functional requirements and interfaces capture processes for a civil aircraft are presented in detail. In particular, the model-based functional analysis process and method are presented. The aircraft functional requirements hierarchy is studied and defined, taking account of the aircraft product breakdown, organization, and statement of work in order to define the requirements topology and traceability relationships. A typical aircraft functional requirements development case is taken to illustrate the functional requirements development method. Furthermore, a requirements management process is depicted throughout the aircraft program life cycle including requirements identification, validation, allocation, verification, and change control activities. A requirements management platform is developed according to the requirements management process. It shows that it is effective to perform functional requirements development based on aircraft operational scenarios (Use Cases) and aircraft program stakeholders’ needs, to improve the completeness of requirements and to ensure engineers’ common awareness of the aircraft to be developed. Furthermore, it’s necessary to perform a common requirements management process throughout the whole aircraft life cycle to ensure that the requirements can be properly validated, satisfied, implemented and verified so that stakeholders’ needs and expectations are met and that aircraft development, operation, and commercial success can be achieved.