Integrated Design of Fluidic Flight Controls for a Flapless Aircraft

Abstract

Fluidic flight controls enable forces and moments for flight vehicle trim and maneuver to be produced without the use of conventional moving surface controls. This paper introduces a methodology for integrated design of Circulation Control (CC) and Fluidic Thrust Vectoring (FTV) as fluidic controls for roll and pitch. The approach is integrated in that drag, mass, volume and pneumatic power requirements are included as part of the overall design cost function. The fundamental flow physics of both CC and FTV is based on the use of a rectangular curved wall jet to control an outer flow, and hence the design approach for each of the controls is similar. A key design driver fluidic controls is the cost of providing a Pneumatic Power Supply (PPS). For gas turbine based systems, the pressure available is usually in excess of requirements so the design implementation is driven by the requirement to minimize mass flow. The proposed design method is applied to the design of CC and FTV flight controls for a Giant Model Aircraft (GMA) class demonstrator aircraft. It is shown that vehicle trim and maneuver requirements for flapless flight can be met with relatively modest system costs using an engine bleed based PPS apart from during landing, where low engine thrust limits thrust vectoring authority and there is limited bleed air available. Copyright © 2008 by the American Institute of Aeronautics and Astronautics, Inc.