Comprehensive Aircraft Preliminary Design Methodology Applied to the Design of MALE UAV

The Structured Design Methods such as Quality Function Deployment (QFD) and Pugh’s concept generation and selection methods have been shown in the industry to improve the problem definition and design synthesis for the new products hence resulting in the better product design. The application is however limited in the aerospace industry, because the decisions are mostly based on the intuition, simplified back-of-the-envelope calculations and few hand-drawn sketches instead of any higher-fidelity design data using Computer Aided Design and Engineering (CAD/CAE) tools. This leads to the skepticism about the findings of such design methods and reduces their wider acceptance and application in the aerospace design. The examples showing significant improvements in the product definition solely based on the computationally supported design methods are almost negligible. This paper describes work undertaken to add quantitative analysis to these methods in order to reduce such deficiencies. A comprehensive approach has been applied to integrate the mission analysis with high fidelity CAD, CFD and FEA tools that in return provide high fidelity data to enter in the QFD matrix or Pugh’s Concept generation and selection matrix. MS Excel spreadsheet coupled to high level CAD and CAE tools has integrated several aircraft design disciplines for the preliminary design phase. The objective is to demonstrate that the application of Design Methods results in better problem specification and solution synthesis when the scores and rankings are based on the CAD and the high fidelity multidisciplinary design data from aerodynamics and structures. The integration methodology is also used to illustrate the unification of two distinct design phases in the traditional design process i.e. the conceptual and preliminary design into one Preliminary design phase. It is suggested that with the integration of CAD and CAE tools, one can perform all the activities and tasks in one unified phase with reduced design cycle time as compared with two separate design phases comprising of two separate teams. The Pugh’s Method is applied to generate, analyze and select the design concepts for a Medium Altitude Long Endurance (MALE) UAV utilizing high fidelity information.