777 Flight Controls validation process

In 1990, Boeing launched the twin-engine Model 777 airplane program to satisfy the needs of airlines in terms of payload and range and to fill a market segment between the Model 747 and 767 airplanes. The 777 airplane is the first Boeing commercial transport airplane to use a full fly-by-wire Flight Control System. The Primary Flight Control System (PFCS) provides manual airplane control and envelope protection in all axes using conventional pilot controls and control surfaces. Stability augmentation is provided in the pitch and yaw axes. The Autopilot and Flight Director System (AFDS) provides steering guidance for manual flight as well as automatic control of the airplane from takeoff to landing roll-out. The autopilot function of the AFDS provides low weather minimum operation down to CAT IIIB minimums. This paper will summarize the 777 Flight Controls validation process for the Primary Flight Control System and Autopilot Flight Director System. The validation process includes the development of the systems requirements to be validated, the methods by which validation is accomplished, the allocation of requirements to the most appropriate validation method, the means by which traceability of this process is maintained, the problem tracking system feedback to the process, and the organizational management of the process. The end result is assurance that the Flight Control System requirements are correct, and the system meets the requirements levied by the airline customers, the certification agencies, and Boeing.