A Variable Stability Flight Simulator is being developed in the School of Aerospace, Mechanical and Mechatronic Engineering at the University of Sydney, Australia. The device is being developed both as a teaching tool for use in flight mechanics courses in the department and as a research tool. It is reasonable to state that learning is enhanced through the experience of concepts outside of the classroom environment. It is intended that the device will be integrated into the department�s teaching program in aircraft flight mechanics. Initial studies centred around a PC based flight simulation developed at the Cranfield College of Aeronautics in the United Kingdom. This system utilises a distributed architecture with several computers connected via Ethernet. It also employs a Primary Image three channel visual system. The system has been further enhanced by the addition of a Link flight simulator provided by the Royal Australian Air Force (RAAF). The RAAF had been using the simulator as a training tool for some years until it had become surplus to requirements. Most of the work in the project has centred around re-engineering this simulator into a viable research/education tool. The Cranfield system has been incorporated into the Link simulator�s hardware to provide a fixed base simulation. The majority of the work described in this thesis revolved around the re-engineering of the flight control loading and motion systems. Previously these items were controlled by analogue circuitry with minimal digital interfaces to the main simulation software. The systems have been re-designed to replace much of the single model analogue circuitry with re-configurable digital control software. Doing so allows changes to be made to the systems in real time through a software interface. The software resides on a common computer that extensively interfaces with the rest of the simulation. To support the hardware involved and to provide for system operation and safety, an extensive Supervisory system has also been implemented. This system along with the motion and control loading software has been implemented in the Matlab / Real-Time Workshop environment. This gives the capability of making real-time changes to any part of the overall simulation. A variable stability module (vsm) is under development. The addition of this module will allow changes to be made to the simulation itself in real-time. The simulator is now functional with the motion and control loading systems operating as designed. Tuning of both systems has been done subjectively by the author. An initial objective analysis of the motion system has been undertaken in an attempt to verify the fidelity of the motion cues generated. A significant outcome of this project has been to create a safe, easily maintainable, re-configurable flight simulator from a large, complex, legacy system. The facility now forms a significant research and teaching tool in areas such as flight mechanics, propulsion, aircraft handling qualities and human factors.

A Variable Stability Flight Simulator is being developed in the School of Aerospace, Mechanical and Mechatronic Engineering at the University of Sydney, Australia. The device is being developed both as a teaching tool for use in flight mechanics courses in the department and as a research tool. It is reasonable to state that learning is enhanced through the experience of concepts outside of the classroom environment. It is intended that the device will be integrated into the department�s teaching program in aircraft flight mechanics. Initial studies centred around a PC based flight simulation developed at the Cranfield College of Aeronautics in the United Kingdom. This system utilises a distributed architecture with several computers connected via Ethernet. It also employs a Primary Image three channel visual system. The system has been further enhanced by the addition of a Link flight simulator provided by the Royal Australian Air Force (RAAF). The RAAF had been using the simulator as a training tool for some years until it had become surplus to requirements. Most of the work in the project has centred around re-engineering this simulator into a viable research/education tool. The Cranfield system has been incorporated into the Link simulator�s hardware to provide a fixed base simulation. The majority of the work described in this thesis revolved around the re-engineering of the flight control loading and motion systems. Previously these items were controlled by analogue circuitry with minimal digital interfaces to the main simulation software. The systems have been re-designed to replace much of the single model analogue circuitry with re-configurable digital control software. Doing so allows changes to be made to the systems in real time through a software interface. The software resides on a common computer that extensively interfaces with the rest of the simulation. To support the hardware involved and to provide for system operation and safety, an extensive Supervisory system has also been implemented. This system along with the motion and control loading software has been implemented in the Matlab / Real-Time Workshop environment. This gives the capability of making real-time changes to any part of the overall simulation. A variable stability module (vsm) is under development. The addition of this module will allow changes to be made to the simulation itself in real-time. The simulator is now functional with the motion and control loading systems operating as designed. Tuning of both systems has been done subjectively by the author. An initial objective analysis of the motion system has been undertaken in an attempt to verify the fidelity of the motion cues generated. A significant outcome of this project has been to create a safe, easily maintainable, re-configurable flight simulator from a large, complex, legacy system. The facility now forms a significant research and teaching tool in areas such as flight mechanics, propulsion, aircraft handling qualities and human factors.

Simulation, whether in-flight or ground-based, is an invaluable tool for testing and evaluating aircraft. Classically, a simulation model is specific to a single particular airframe, only able to model those flying characteristics. Vast information can be gained from a simulation that is able to model a wide range of aircraft, through a comparison of the performance of these aircraft. Such a variable stability simulation model was created based on 46 stability parameters, including natural frequencies, damping ratios, time constants, and gains. The simulation was obtained using transfer functions representing the aircraft state responses to control inputs. These transfer functions were converted into state space systems used to create the linear equations for the model. The model was first developed as a desktop simulation and then converted for use with the Virginia Tech's 2F122A flight simulator. This conversion required a simple dynamic inversion of the body axis force and moment terms. To reduce the error in these terms, a model following scheme was incorporated. A series of canned inputs and real-time pilot-in-the-loop tests were flown to evaluate the variable stability model. Results in this paper have demonstrated the successful creation of a variable stability simulation model. / Master of Science