An Integrated Aircraft Design and Performance Prediction Tool-Design, Validation, and Demonstration

Abstract

When starting on an aircraft design process, it could prove powerful to be able to employ a design tool which has the ability to predict an aircraft’s aerodynamic, longitudinal static stability, and flight performance characteristics without paying the large time penalty typically associated with these efforts. An integrated aircraft design code, iFly, was created in order to serve as a design tool which presents data to compare different aircraft with varying airfoils, engines, aerodynamic devices, planform features, and dimensions with respect to their aerodynamic coefficients, longitudinal static stability characteristics, and basic flight performance qualities while completing a simple flight mission. Executing the user-friendly graphic user interface, the user has the ability to define and generate numerous aircraft of varying configuration and size to run analysis on and compare results. The ability of iFly to perform a multi-aircraft analysis based on a set of user-defined iteration parameters of chosen aircraft dimensions, allows for the user to select a configuration that has been optimized with regards to its specific mission requirements and objectives. After the user has defined the aircraft geometry and features, iFly predicts aerodynamic coefficients for the particular configuration using an advanced potential flow code. Once these coefficients are generated, the aircraft configuration is ‘flown’ through a user-defined basic flight mission, and the subsequent performance parameters are collected. Predicted aerodynamic and flight performances that are generated using iFly agree well with experimental data from several small-scale Unmanned Ariel Vehicles (UAVs), and a potential flow code XFLR5. In addition, the potential of iFly is demonstrated with the design process of Saint Louis University’s Advanced Class and Micro Class entries to the 2011 Society of Automotive Engineers’ Aero Design Competition. The code validation of iFly and the example of the SAE Aero Design aircraft, demonstrate the possibility of the code to greatly reduce the time cost of the aircraft design process by providing reliable aerodynamic and performance data.