Digital Flight Control: An Approach to Efficient Design

Previous digital design experiences provide guidance and offer solutions for one of the newest digital technology applications: The commercial transport AFCS. In addition to facing well-documented problems of software control and maintainability, operational safety adds a new dimension to the requirements for software reliability. After a general discussion of the problems encountered in past digital system programs, this paper addresses the specific requirements of the commercial transport system and their implications in terms of system architecture and software development. An immproved solution to the problem of software design is offered, and its impact on traditional and future problem areas is outlined. A description of a prototype digital AFCS under development is presented. The experiences to date with this system reinforce the correctness of techniques and approaches used in its development.