Overview

Chapter 6 illustrates how to arrive at a preliminary aircraft configuration of a new project starting from scratch, with the expectancy of satisfying the market specification. To progress further, the next task is to lay out the undercarriage (also known as the landing gear) position relative to the aircraft CG, which is accurately established in Chapter 8. This chapter addresses the undercarriage quite extensively but not the detailed design; rather, it focuses on those aspects related to undercarriage layout and sizing during the conceptual study phase. More details on undercarriage design are in the cited references.

This chapter first introduces the undercarriage to serve vehicle ground handling, followed by basic definitions, terminologies, and information used in the design process and integration with an aircraft. Finally, methodologies for layout of the undercarriage and tire sizing are presented to complete the aircraft configuration generated thus far. Considerable attention is required to lay out the undercarriage position and to determine tire size and geometric details to avoid hazards during operation. This book limits the topic to the fundamentals to the extent of the requirements for positioning the undercarriage and sizing the wheels and tires. These fundamentals are shown schematically in the three-view aircraft drawings. Relevant information on wheel tires is also presented in this chapter.

The undercarriage is a complex and heavy item and, therefore, expensive to manufacture. It should be made right the first time.