The application of the wings with a high aspect ratio for future-oriented transport category aircraft is being considered. Such a solution makes it possible to increase fuel efficiency by reducing induced drag. This goal is achieved by increasing the wingspan, when the wings made of composite materials are used. The wings of an increased span complicate the arrangement of the aircraft in the existing infrastructure of airports. To eliminate this drawback, the application of folding wingtips was considered. The effect of such a folding device on the mass of the airplane was estimated. The approach to estimating the mass of composite structures with folding wingtips has been proposed. A conceptual assessment of the Boeing 737 and A-320 aircraft with higher aspect ratio composite wings was performed.

Nowadays there are a lot of startups about creation of UAVs for civil application. Most of them are based on electric (batteries) or traditional fuel (oil-based) technologies. From other side, requirements of ICAO about reducing environmental impact of civil aviation are pushing aviation companies to develop green technologies. Some of them are based on hydrogen fuel application. Application of hydrogen can reduce the environmental impact of aviation. The aim of this chapter is to analyze possible trends of civil unmanned aircraft application and to evaluate the possibility and efficiency of hydrogen fuel application for such drones. It was demonstrated that the implementation of hydrogen technology in civil drones presents significant challenges that necessitate comprehensive examination. The two technologies, when considered separately, offer a plethora of advantages. However, when combined, they can potentially lead to undesirable outcomes. On the one hand, they can contribute to an improvement in the environmental impact. On the other hand, they possess unique characteristics that interact with one another. It has been demonstrated that the integration of hydrogen fuel can result in an 8% increase in the mass of the drone, which subsequently reduces its overall efficiency.

The purpose of this research is to improve the approach for evaluating of new design solutions based on sensitivity analysis of takeoff mass (SFM) to initial changes in the basic project. The approach is based on the changes assessment in maximum takeoff mass of a developed project or an already existed basic variant of an aircraft with local design (project) changes, including the aerodynamic ones, that ensure the developing of a more advanced aircraft. In comparison with the existed known approaches based on the mass growth factors, which were considered constant, the proposed approach takes into account more exactly the dependence of the takeoff mass on the initial local change in mass in terms of their functional purpose, as well as the aerodynamic characteristics. This approach allows the designer to calculate more precisely the final maximum takeoff mass changes in the early (preliminary) stages of conceptual design when looking for new design solutions. On numerical examples, carried out on the examples of transport category airplanes, a significant dependence of the wing aspect ratio influence on fuel efficiency is shown. The considered approach using SFM with semi-analytical aerodynamic analysis combination is simple, reliable and convenient in the analysis and synthesis of a new project for the design process based on the base variant.

Fuel efficiency is one of the most important parameters for the estimation of efficiency of passenger transport category airplanes. The level of fuel efficiency depends on some parameters. The objective of airline profitability depends directly on its aircraft operating economics and upon its compliance with international requirements for safety and ecology. This paper examines the fuel efficiency of a range of Russian, American and European passenger aircraft, and statistical data considering their era of design and production as well as the volume of their transport operations is presented and analyzed. It is shown that the improvement of fuel efficiency is crucial in their operation. Informational models for fuel efficiency for flight and hourly capacity are given. By using fuel efficiency parameters, analytical models based on a comparison of regional jets with passenger capacities of up to 110 people are solved, and, based on this research, some findings on their effectiveness are presented.

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.

In modern time the aircraft variants creation is main trend in the aviation industry. One the aspect of the aircraft safety is its safety take-off [1]. The aircraft parameters like relative take-off weight and thrust-to-weight ratio can determine many its performance include take-off. Their influence on decision speed during take-off of modified transport category airplanes are explored. The analytic model is simple and high efficiency way for the first approach of airplane`s safety analyses. The problem is solved by analytics modelling airplane motion on runway during take-off. Quantitative estimation of influence of the airplane weight and thrust-to-weight ratio variation on decision speed of continued or aborted take-off with critical engine failure is given on the base of example of heavy cargo airplane. The application of this way for the airplanes safety analysis is important for each types of aircraft. Estimation model is given in dimensionless parameters and so is applicable for any type of transport category airplanes.