2 ND EUROPEAN CONFERENCE FOR AEROSPACE SCIENCES (EUCASS) Copyright 2007 by B. Dolega and A. Tomczyk. Published by the EUCASS association with permission. B. Dolega and A. Tomczyk Rzeszow University of Technology, Control and Avionics Department W. Pola 2, 35-959 Rzeszow, Poland In this paper, a proposition of the perspective solution of the general aviation aircraft control system is presented. The main idea of the project is to use the specialized indirect (Fly/by/Wire) control system. This control system should shape handling qualities of an aircraft in such a way that control becomes easy and safe. Such a system may be considered to be pilot’s electronic assistant as it integrates simplified handling flight controls and autopilot functions, and reduces the complexity of interactions among aircraft attitudes, power settings, and rate of motion, and in conclusion limits the possibility of loss of control. The flight control system was implemented for PZL / 110 "Koliber" aircraft. Preliminary laboratory tests and flight testing of this conception shows its pilot/friendly qualifications, e.g. it can assist pilots with limited aviation training. General aviation aircrafts ought to be available to a large group of people. A lot of them haven’t high experience in pilotage, they dream about aircraft which is easy in piloting, economic and safe. For these pilots pilotage should be similar to 3D car driving 21 . Another group of the general aviation pilots highly value the planes which enable freedom in the decision how to proceed, instead of following rather fixed procedures (e.g. IFR). Advances in modern flight control system 6 provide specified behaviour of the aircraft set by the pilot. Flying qualities could be adopted to the pilot requirements. Indirect Flight (Fly/by/wire) control technology from few years has been used in other type of aircraft 15 to satisfy similar requirements. Through many years, high integrity design and difficult validation through a certification process make this method very expensive and unprofitable in general aviation. Avionics advancements make this control technology usable in general aviation today 7,10,11,16 . Avionics and Control System Department of Rzeszow University of Technology from few years made researches of fly by wire control system for general aviation aircrafts. Flight tests of this system proved 20 the brief for the design of this system. The basic idea of the project is to employ an indirect (Fly/by/Wire) software/based flight control system 18 characterized by high degree of automatization, leading to an almost “unmanned” general aviation aircraft. “Unmanned” does not mean eliminating humans from the control process, but changing their role in the system. We are sure, that this way is the future of general aviation 7 but using this method also indicates requirements to achieve the high reliability. It was one of the main goal of our last researches. In the event of major failures, especially in flight control system, an approach to reconfiguring this system as fault effects protection method is typically applied. The reconfiguration approach relies on the structural and parametric changes when faults are detected and identified. Synthesis of the fault detection and identification methods connected with reconfiguration needed a lot of theoretical and semi/practical researches. The practical implementation of reconfiguration in the fly/by/wire control system conducted in our Department was strongly connected with all presented requirements 3 . The most important is taking into consideration in the reconfiguration tasks the pilot/aircraft reasoning. ! Control system is a very important in flying safety. When structure of this system is simplex (single inputs/ single logic solver/ single outputs) a single fault results in the loss of protection and/or unnecessary shutdown. The effects of their failures are catastrophic. The redundant structure (multiple inputs/ multiple processors/ multiple outputs) make the system tolerant for the single failures. It is made by the reconfiguration process. The second, very important for control system designer fact is its airborne status. Faults appearing cannot interrupt the mission or can