Coordinated flight control along a complex flight-path

In order to design robust feedback control systems we must be able to accurately measure the states of the system we desire to control. Though a number of issues remain to be resolved, global positioning system sensors and miniature inertial and rate sensing instruments together with conventional air-data systems will soon provide inexpensive integrated measurement systems for aircraft that will provide accurate measures of linear and angular positions and velocities as well as air speed, angle-of-attack, and side-slip. The availability of measurements of these states provides the opportunity to design new integrated flight control systems that are capable of properly controlling aircraft along complex coordinated flight paths. The National Aeronautics and Space Administration (NASA) and the Federal Aviation Administration (FAA) are proposing a research, development, and deployment effort called the Small Aircraft Transportation System (SATS) that envisions a large fleet of small aircraft flying autonomously in non-towered, non-radar airspace in near all-weather conditions. In this paper we present an analysis of the characteristics for a flight path modeling system that will support the operation of such an integrated navigation and flight control system. For one system we derive the algorithms to compute the required state values. This leads to a new analytical definition of coordinated motion by which we are able to compute the required attitude and angular velocity to properly follow the prescribed flight path. The output of the flight path modeling system (desired value of linear and angular position and velocity, angle of attack, sideslip angle, and thrust) can be used in either an integrated navigation and control automation system or to drive displays (highway-in-the-sky) to provide pilots with integrated navigation and attitude control cues