An approach to aircraft subsystems design and integration

Aircraft Vehicle Management System (VMS) and subsystem design requirements emphasizing significant improvements in performance, maintainability, reliability and life cycle cost over existing subsystems, demand the implementation of design and analysis tools which aid the aircraft VMS and subsystem designer in the process to optimize individual subsystem designs within the constraints of the overall aircraft configuration optimization. Modern design processes incorporating a combination of new and existing software programs are being implemented at Rockwell International and other airframe manufacturers to provide designers with capabilities leading to significant productivity improvements. This paper describes the design philosophy and methodology and the preliminary mechanization of the "top down" design process for aircraft subsystems. The software incorporates expert system technology and provides extensive design databases in the form of rules based on expert designer experience, existing design libraries derived from actual designs an "lessons learned" files. The software tool uses commercially available expert system "shells" for rule-based and case-based methods to minimize the development and maintenance cost. Interfaces to existing analysis and synthesis software programs are provided to take advantage of previous developments. The program also provides a direct interface to available Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) tools, thereby minimizing the cost and complexity associated with concurrent engineering and the transition from conceptual to preliminary design phases.