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The purpose of this work is to further develop the methodology for calculating the aircraft take-off mass and its main functional components for the conceptual analysis and synthesis of new projects.

The method is based on the assessment of changes in the take-off gross mass (TOGM) of the already developed project or already existing a basic version of the aircraft when making local mass changes for its modification or for the numerical researches to create a more advanced project. The method is based on the “sensitivity factors of mass” (SFM) of aircraft, which represents the ratio of TOGM to initial (local) mass changes of its main functional components. The method of analytical refined calculation of SFM for the initial mass change and the main aerodynamic characteristics is given.

In comparison with the long-known method based on weight (mass) growth factors, which were considered constant, this method takes into account the dependence from the value of the initial local mass change and its functional purpose.

This method allows the designer to calculate more strictly the final changes in the TOGM on the initial stages of conceptual design when finding new project solutions. Numerical calculations are given on the example of passenger aircraft. The dependence of SFM and TOGM and its functional masses on the value of the initial change of the structure mass are shown. This method is used in the educational process at the college of Aerospace Engineering in the Aircraft Design department.

The considered method based on SFM is simple and convenient and more accurate for conducting project research on many project parameters when analyzing and synthesizing a new project.

The purpose of this paper is to present an overview of the aircraft design problems which can be efficiently solved using a special solid finite‐element model of variable density.

Optimization algorithms based on fully‐stressed design philosophy, sensitivity coefficients, and employing material density as a design variable provide means to generate optimal topology layouts, subject to a wide range of design constraints. A novel non‐dimensional criterion is used for assessment of load‐carrying efficiency of structures and knowledge accumulation.

Variable density model, together with non‐dimensional criterion of structural efficiency, yields a new versatile approach to a structural weight estimation at early design stages. New weight equations are used. The approach is a powerful tool for addressing complex multidisciplinary design optimization (MDO) problems such as aerodynamic load prediction taking aeroelastic deformations into account and aerodynamic‐structural design optimization of unconventional aircraft configurations.

For accurate estimation of wing weight and deflections, the method should be tuned by regression analysis of existing aircraft to properly account for secondary structural weight.

The developed software tools for aeroelastic behaviour prediction and coupled aerodynamic‐structural design optimization are ready for integration into the complex MDO framework.

The variable density model is shown to have broad predictive opportunities for design problems at early stages of a product development.

The purpose of this paper is to propose a solution of the engine bypass ratio choice problem of a very light jet (VLJ) class aircraft using the multiple objective optimization (MOO) method.

The work focuses on the choice of one of the most essential parameters of the jet engine, that is its bypass ratio. The work presents the methodology of optimal designing using the multitask character of the matter which is based on the mathematical model of optimization in the concept of the set theory. To make an optimal choice of the chosen parameter, a complete computational model of an aircraftwas made (aerodynamic, power unit, performance and cost) and then the method that allows to choose the bypass ratio was selected, regardingmultiple estimating criteria of the obtained solutions. The presented method can be used at the concept design state for determining the chosen and most important technical parameters of the aircraft.

The way to design a competing aircraft is to choose its design parameters, including the power unit, by using the advanced methods of MOO. The main aim of the work was to demonstrate a method of selecting chosen parameters of the transport aircraft at the preliminary design stage. The work focuses on the choice of bypass ratio of the jet engine of the VLJ. The method could be helpful at the preliminary design stage of a new aircraft to selection of other design parameters.

The exemplary calculations were made for 50 different transport tasks to take into account different performance conditions of the aircraft. The presented method can be used at the concept design state for determining the chosen and most important technical parameters of the aircraft.

The work shows a practical possibility to implement the proposed method. The presented method could be helpful at the preliminary design stage of a new aircraft to select its design parameters. The results of the analyses are a separate point for further research and studies.

The work shows a practical possibility to implement the proposed approach for design problems at early stages of product development.

The purpose of this paper is finding the optimal geometric parameters and developing of a method for optimizing a light unmanned aerial vehicle (UAV) wing, maximizing, at the same time, its endurance with the assumed parameters of aircraft mission.

The research is based on the experience gained by the author’s contribution to the project of building medium-altitude, long-endurance class, light UAV called “Samonit”. The author was responsible for the structure design, wind tunnel tests and flight tests of the “Samonit” aircraft. Based on the experience, the author was able to develop an optimization process considering various disciplines involved in the whole aircraft design topics such as aerodynamics, flight mechanics, structural stiffness and weight, aircraft stability and maneuverability. The presented methodology has a multidisciplinary nature, as in the process of optimization both aerodynamic aspects and the influence of wing geometric parameters on the wing structure and weight and the aircraft payload were taken into account. The optimal wing configuration was obtained using the genetic algorithms.

As a result, a set of wing geometrical parameters has been obtained that allowed for achieving twice as long endurance as compared with the initial one.

Using the methodology presented in the paper, an aircraft designer can easily find the optimum wing configuration of a designed aircraft, satisfying the mission requirements in a best way.

An original procedure has been developed, based on the actual design, wind tunnel tests and numerical calculations of “Samonit” aircraft, enabling the determination of optimum wing configuration for a small unmanned aircraft.

The paper aims to present a way of engine model integration, an aircraft (multitask) and the mission into the single model that allows to study, from the level of selection of the engine cycle parameters, the feasibility of a specific mission with the assumed aerodynamic characteristics exemplified by a multitask airplane.

There were introduced dimensionless geometric and energetic criteria, binding parameters of the engine and the airplane. The following models were built: of the turbofan engine and the aircraft movements with the application of these criteria, creating a dimensionless model allowing for measuring the impact of engine design parameters on the efficiency of the mission undertaken.

The results were limited to the presentation of the impact of circuit parameters, such as engine TIT, OPR, BR on the defined criteria. The application of dimensionless criteria reduced the dimension of the task.

The presented method can be useful for engineers involved in the task of engine integration and the airplane at the preliminary design stage.

The originality of the presented solutions is reduced to provide a different, unconventional approach to the design process and not (so far) the engine itself but the entire aviation system.

A proposal of the perspective solution of the general aviation aircraft control system is presented. The objective of the proposed concept for the control system is to assist pilots with limited aviation training by: automatic stabilization of the aircraft's attitude, altitude, airspeed, and heading and decoupling of the flight controls. The structure and main functions of the control system is presented, and method of control laws synthesis is proposed. Flight control system is based on the model‐following design technique. Two kinds of flight control systems are taken into consideration. The first solution is based on the optimal full‐state feedback controller, the second one is the simplified controller, using the easy observed states for feedback loop only. The project calculation of the flight control system for PZL‐110 “Koliber” aircraft, computer simulations and preliminary flight testing results will be presented.

The purpose of this paper is to present application of multidisciplinary design optimisation (MDO) in redesign of a small composite aircraft. The redesign process was integration of the turboprop engine in a small composite aircraft. The process requires cooperation of specialists from many disciplines and definition of their tasks. For selected tasks, the authors present results of the calculation.

The authors used collaborative optimisation (CO) algorithm to solve the problem. They decomposed this complex process into a set of tasks in different engineering/research disciplines and used techniques and methods specific for each task (research/engineering discipline) to find a proper solution. The computer-aided design (CAD), computational fluid dynamics (CFD) and computational structural mechanics (CSM) commercial software were used as common tools as well as intentionally developed computer programmes were used as basic tools in some tasks, in particular, for aerodynamic optimisation, calculation of load and stability of aircraft. The exchange of data between separate tasks allowed achieving the main goal of complex design process.

Selected optimisation algorithm, CO, proved efficient for the authors’ purposes. The effectiveness of multidisciplinary optimisation depends as much on organisational parameters as it does on technical and technology parameters.

Multidisciplinary optimisation needs to be an integral part of analysis and design process. The successful optimisation results allowed to meet the requirements and to proceed to the next phase of work – preparing technical documentation for manufacturing the components necessary for integration of the airplane with the new engine.

Presented results of design process are a valuable example of how to achieve the final goal in an ongoing project.

The purpose of this paper is to understand the competitive landscape of emerging market economies (EMEs) and the implications of business models and strategies used by multinational enterprises (MNEs) to enter and operate in such landscapes. It does so by considering the aviation sector in an emerging economy – India, and by studying the strategies pursued by AirAsia India – the Indian joint venture of AirAsia Investment Limited and Tata Sons..

The paper follows a case study approach. Secondary data sources from the library, company website and newspaper articles have been used to build a case that would encourage students to discuss and analyze the competitive strategies followed by MNEs in EMEs.

Emerging markets offer attractive investment opportunities to MNEs across several industries. However, their markets for intermediate goods and services possess imperfections. Competitiveness in such markets will require going beyond country-specific and firm-specific advantages. MNEs will need to integrate location-specific advantages with internalization advantages of these market imperfections to operate successfully in the complex environments of EMEs. A one-size-fits-all approach of transposing successful strategies from home markets will fail to create value.

MNEs, such as AirAsia, will need to develop participatory skills to leverage the location-specific-advantages of EMEs and reduce their own curse of foreignness to be able to succeed in EMEs.

This paper contributes to extant literature by studying the competitive strategies pursued by a global leader in an EME. The case of the “World’s Best Low-Cost Airline” – AirAsia’s India operations seeks to go beyond the Eclectic Paradigm and the country-specific and firm-specific advantages framework, to provide a location-internalization paradigm for operating in EMEs.