Methods for Conceptual Flight Control System Design

Abstract

The traditional approach in aircraft conceptual design sizing for stability and control employs the so called “Tail Volume” method, which basically establishes static stability of the design via empirical handbook methods. The methodology dispenses with any formal definition of the Flight Control System architecture and topology, and, does not afford visibility of critical sizing scenarios to the designer. This situation creates a measure of uncertainty when attempts are made to model the flight physics problem, thus thwarting opportunities in performing an advanced assessment of flight handling qualities. This paper reviews the work-in-progress status of an innovative software package aimed at the conceptual design phase called Flight Control System Designer Toolkit (FCSDT) that permits Flight Control Systems architecture definition for primary and failure modes, facilitates generation of control laws, assists the designer in apportioning control allocation schedules, and finally, analyse the stability and control of aircraft models. Results regarding flight control system architecture design are based on a control surface layout obtained from the Boeing 747 technical manual. Stability and control assessments were based on aerodynamic data generated by the aerodynamic model builder interface to Digital DATCOM provided by the European funded Framework 6 Program based on the Boeing 747 geometry.