AIRCRAFT DESIGN IN THE 20TH CENTURY

The Impact of Changing Capability and Performance requirements on Aircraft Design in the 20th Century



The Impact of Changing Capability and Performance Requirements on Aircraft Design in the 20th Century

Introduction

The aircraft design in the 20th century process generally commences with the identification of a "what" or "desire" for something and is based on a real (or perceived) deficiency. As a result, a system requirement is defined along with the priority for introduction, the date when the system capability is required for customer use, and an estimate of the resources necessary for acquiring this new system. To ensure a good start, a comprehensive statement of the problem should be presented in specific qualitative and quantitative terms, in eNough detail to justify progressing to the new step.

As the name implies, the aircraft conceptual design phase is the aircraft design at the concept level. At this Stage, the general Design requirements are entered in a process to generate a satisfactory Configuration (Groover, 2010). The Primary tool in this stage of design is the "selection". Although there are variety of evaluation and analysis, but there are no much calculation. The past design experience plays a crucial role in the success of this phase. Hence, the members of conceptual design phase team must be the most experienced engineers of the corporation (Niu, 2005).

Figure 3.1 illustrates the major activities which are practiced in the conceptual design phase. The fundamental output of this phase is an approximate three-view of the aircraft that represents the aircraft configuration. Section 3.2 concerns with Primary function and role for each aircraft Component. The aircraft Components (e.g. Wing, Fuselage, tail, Landing gear, and engine) Configuration alternatives are addressed in Section 3.3. Aircraft classifications from variety of aspects are reviewed in Section 3.4. In Section 3.5, the principles of trade-off analysis to determine the most satisfactory configuration are introduced. Section 3.6 examines the conceptual design optimization with an emphasis on the application of the multidisciplinary design optimization technique (Rao, 2004).

Primary Functions of Aircraft Components

An aircraft comprised of several major components. It mainly includes Wing, Horizontal tail, Vertical tail, Fuselage, Propulsion system, Landing gear and control surfaces. In order to make a decision about the configuration of each aircraft component, the designer must be fully aware of the function of each component (Chong, 2008). Each aircraft component has inter-relationships with other components and interferes with the functions of other components.

Wing

The main function of the wing is to generate the aerodynamic force of lift to keep the aircraft airborne (Onwubiko, 2000). The wing tends to generate two other unwanted aerodynamic productions: an aerodynamic drag force plus an aerodynamic pitching moment. Furthermore, the wing is an essential component is providing the aircraft lateral stability which is fundamentally significant to the flight safety. In almost all aircraft, the aileron is arranged to be at the trailing edge of the outboard section. Hence, the wing is largely influential in providing the aircraft lateral ...