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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.

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.

In this work, sailplane symmetrical motion equations including pitch motion controlled by elevator angle are presented. The following effects are especially taken into consideration: i) tail damping due to pitch motion; ii) air density variation according to altitude; iii) presence of vertical and horizontal atmospheric air motions, and iv) non-linearity of CL ′ a curve near stall angle. The mathematical modeling includes the construction of an objective function for competition flight optimization. Making use of the concept of state variables, the minimum time trajectory problem is formulated as an optimal control problem with state constraints. Using simplified control laws and a mathematical programming algorithm, suboptimal trajectories are obtained for the sailplane PIK-20B.

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 describes the design of an International Formula One (IF1) racing airplane wing. The first step consists in the simulation of the airplane flying on the race track to obtain details about the condition in which the wing needs to be designed and optimized. The paper describes the details and formulation used to perform this simulation using parametric flight paths and a point model dynamic model. A scheme analytically obtains the control laws for the simulation with Frenet-Serret frames over the parametric flight path. Two different airplanes, with different power levels, are simulated on a typical IF1 race track to determine the range of lift coefficient in which the wing must be designed. Based on this lift coefficient range, a set of four new airfoils are designed based on the NLF0414-F airfoil. Their usage over the wing span is determined, using nonlinear lifting line method to assure that during races the wing operates inside the laminar drag bucket.