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The performance and flight characteristics of an aircraft are markedly affected by the aerodynamic design, which can be done making use of various tools such as wind tunnel tests and computer simulations. Despite the fact that wind tunnel testing permits great trustworthiness of results, they are still slow and costly procedures. On the other hand, computational methods allow for faster and lower budget analysis. For the conception and the initial phase of an aircraft design, where it is necessary to evaluate a great variety of wings and lifting surfaces configurations, it is desirable to have a method able to determine the main aerodynamic characteristics, such as drag and lift, quickly. In more advanced phases of the design the interest is in obtaining results which shows a more detailed flow around the aircraft.

This paper presents the design process of an UAV (Unmanned Aerial Vehicle) for general civil purposes. The aircraft was designed to serve as test platform for the autonomous flight controller developed by the SIDEVAAN project (System Development for Autonomous Aerial Vehicle) of the Federal University of Minas Gerais. Procedures used for aircraft conception and manufacturing are described. Aerodynamics, stability and control, performance and loads calculations are presented including particular design methods applied specifically to light aircrafts. Details concerning computational procedures used are included and constructive solutions during the manufacture process are presented.

The present paper presents a method for the numerical determination of control laws for aircrafts needed for optimization of a pre-established maneuver, applied to a take-off under requirements of FAR-Part 23. The methodology is based on the minimization of penalty functions through of mathematical programming algorithms with numerical integration of the aircraft equations of motion. With the optimum control law it is possible to elaborate efficient strategies for automatic flight control and for orientation of piloted flights. Numerical aspects of the application of this procedure are discussed, these being important for their adequate performance. Results are obtained for the optimization of the take-off distance of a tail-wheel airplane and are compared with the take-off distance obtained by manual control.

Recently, the development of Unmanned Air Vehicle (UAV) has been an important activity in Brazilian Aerospace Research Centers and Universities. The major of these enforcements has been focused in the development of medium size UAV's for aerial reconnaissance. Particularly, the CEA-UFMG, start an effort in order to develop a small size UAV (SUAV) able to execute aerial reconnaissance of small areas. This work present the most important phases of the development process of this SUAV. For the construction of computational models for the flight dynamic simulation and the calculation of aerodynamics characteristics of aerial platform several in-house developed codes was used. With these computational tools became possible to design the guidance and automatic control strategies. Initially the strategies were developed for each motion in separated, and finally they are grouped for test ant tune in the 6DOF simulator. Details of embedded hardware and software are presented.

Advances in aircraft crashworthiness can be achieved by the development of crashworthy composite fuselage concepts. To attend the design requirements that will be established by the next generation of general aviation aircraft, the present work presents an innovative composite fuselage section concept that besides its added crashworthiness features represents a great potential for weight and manufacturing costs reduction.

To attend the next generation of aircraft, which will demand higher levels of crashworthiness performance and occupant safety, the development and validation of reliable simulation tools is a very important task. Through efficient use of finite element simulation technologies, development costs and certification tests can be reduced, while meeting aircraft safety and crashworthiness requirements. The present work presents an overview of aircraft crash and occupant simulation, highlights selected topics of the finite element crash technology, review recent applications, and identify future challenges of the technology.

This paper present the instrumentation procedure used in order to determine the performance, stability and control characteristics of the light aircraft CEA-205 CB-9 Curumim. The instrumentation used is: i) autonomous acquisition system using micro controllers; ii) solid state inertial platform; iii) pitot probe; iv) attack and sideslip angle indicators; v) potentiometer on control system; vi) load cell on control system; vii) propeller tachometer; viii) barometer; ix) thermometer and x) GPS. Assembly and calibration detail procedures are presented with some results obtained on typical maneuvers. This work, in development on the Center for Aeronautical Studies of Federal University of Minas Gerais (CEA/UFMG) and on the Department of Aeronautical Engineering of Naples University (DPA), intend to assembly a system in order to perform low cost flight tests on light aircrafts.

This paper presents the computer implementation process of the Panel Method for aerodynamic analysis of three dimensional bodies with or without lift. The computer implementation consists in the creation of pre and post processing environments and a solver for the solution of the problem in external flow potential over three dimensional bodies with and without lift. For cases in which there’s no lift, a constant distribution of sources over the body (fusaleges, farings, etc.) is used, their intensities calculated in order to guarantee impermeability of the body. For cases in which there is lift, a constant distribution of sources and doublets are used on the body (wings, tails, etc.). The intensity of the sources is solved in the same manner as cases with no lift. Intensity of doublets is solved in order to satisfy the equality condition regarding pressure on the under and upper side of the trailing edge (Kutta Condition) of the body without lift.

One of the critical tasks of aircraft design is the definition of mass of aircraft's main items, and the aircraft mass distribution. Depending on the type of aircraft (e.g. commercial, general aviation, highly-maneuverable) different types of mass distribution data or trend curves are available; and in general these curves are based on the existing aircraft. But some lack of data is noticeable in terms of solar aircraft, i.e. the available information in terms of mass trends does not fulfill the needs of the designers of this type of aircraft. Considering this perspective, the main motivation of this study is to provide some information, in terms of mass trends and mass analysis for sun-powered aircraft, which could fill part of the gap, and stimulate other efforts in the same direction. Through this work, studies of mass breakdown of different examples of sun-powered aircraft are presented.