Flight Investigation and Theory of Direct Side-Force Control

Abstract

Several side-force command modes were tested in Princeton's six-degree-of-freedom (6-DOF) variableresponse research aircraft (VRA), emphasizing the requirements of crosswind landing and lateral offset nulling. Pilot input modes included proportional and rate thumb switch, lateral stick, and foot pedal motions to command pure lateral acceleration, pure sideslip angle, and flat-turn maneuvers. Flight test results and supporting theoretical development are presented here. It is shown that a third-order dynamic model can be used to define control surface interconnects for decoupled side-force commands. Pilots' opinions regarding desirable command modes for the landing approach were shaped by their primary flying experience, although there was consensus that side-force commands that are uncoupled from conventional control inputs are preferred.