Abstract:
The Handling Qualities (HQ) Simulator is a software developed to study the Handling
Qualities of a Fixed Wing aircraft based on the aerodynamic coefficients and flight
conditions. This software would indicate if the aircraft would be stable, unstable or
neutrally stable under these conditions. In this HQ Simulator, one can input the vital
aerodynamic coefficients of a newly designed aircraft (or an existing aircraft) and the
software will indicate if the aircraft is going to be stable or unstable depending on specific
pilot input. HQ Simulator has two main parts, first part calculates Longitudinal handling
qualities and the second part calculates Lateral & Directional handling qualities. The
longitudinal handling qualities part of the simulator shows the change of angle of attack,
pitch rate and pitch angle in real time and the lateral & directional handling qualities part
of the simulator shows change of sideslip angle, roll rate and yaw rate in real time.
Additionally, the software is designed to display a simulation of that aircraft using an open
source flight simulator called FlightGear. Presently, three standard types of simulated pilot
inputs can be given to the aircraft using the software, namely Doublet, Pulse and Step input.
The amplitude, duration and starting time of the inputs can also be specified by the user.
For this study, the aerodynamic coefficients of General Dynamics F16 Fighting Falcon are
given as default in the simulator. The user can change the aircraft parameters easily. The
user can also select other aircraft using a dropdown menu. To validate the results of the
Handling Qualities simulator, another software was developed which takes the governing
6DOF (Six Degrees of Freedom) Longitudinal and Lateral-Directional equations of motion
and calculates the modal parameters of the response. This will greatly help the user to
classify the type of the aircraft and the level of flying effort required with respect to the
Handling Qualities Rating (HQR) given by using Cooper Harper Scale. Designers of Auto
stabilizers, Autopilots and Fly by Wire systems can use this simulator to study the effect of
their systems before they are installed on the aircraft. Thereby helping in saving crucial
man-hours, flight test effort and human life.
