The safety and risks of civil aircraft operation depend on a lot of factors. One of them is the structural features of an aircraft. In aviation history, there are examples when “non-rational” design solution was the reason for crashes, but there are examples about successful civil aircraft that have “rational” structure and long operational time without critical incidents. So, how can a designer provide high safety of level and decrease incidents’ risks in time of a regular aircraft operation? This chapter partly can help to understand some reasons and approaches for providing “rational” aircraft structure. Design solutions can be divided into some groups by some common features and requirements. They are maintainability, serviceability, accessibility, labor effort decreasing, weather requirements, transportation, etc. All these groups depend on engineers’ structural solutions. They are interdependent and often contradictory. In other words, if one of the features will be better, another will be worse at the same time. And, a designer must remember all the time about this and try to find compromise between different requirements. The successful commercial aircraft is composed of a set of rational design solutions for these specific tasks.
Part of the book: Safety and Risk Assessment of Civil Aircraft during Operation
Modern composite materials (CM) have wide applications in airframe structures of transport category aircraft. Their application has an important place in providing the minimum mass of an aircraft structure. The successful implementation of CM in airframe structures is directly related to the creation and improvement of computational methods for assessing their strength and stiffness. The most complex task of CM application is to provide the required level of strength and stiffness of separate structural elements and a whole unit. Currently, many methods have been developed to evaluate the strength of CM structural elements. Much attention is paid to the problems of fracture mechanics of CM. Numerous different criteria for fractures of a composite product have been developed, but the question of their unambiguous selection still remains open. In this situation, in order to make a reasonable choice of this or that criterion, additional computational-experimental research in relation to a specific structure is necessary. In this chapter, some aspects of strength determination of a CM aircraft wing have been analyzed. Some aspects of such evaluation have been considered.
Part of the book: Fiber-Reinforced Composites - Recent Advances, New Perspectives and Applications [Working title]