Thesis (M.S.)--University of Florida, 2005. / Title from title page of source document. Document formatted into pages; contains 42 pages. Includes vita. Includes bibliographical references.

abstract: There are significant fuel consumption consequences for non-optimal flight operations. This study is intended to analyze and highlight areas of interest that affect fuel consumption in typical flight operations. By gathering information from actual flight operators (pilots, dispatch, performance engineers, and air traffic controllers), real performance issues can be addressed and analyzed. A series of interviews were performed with various individuals in the industry and organizations. The wide range of insight directed this study to focus on FAA regulations, airline policy, the ATC system, weather, and flight planning. The goal is to highlight where operational performance differs from design intent in order to better connect optimization with actual flight operations. After further investigation and consensus from the experienced participants, the FAA regulations do not need any serious attention until newer technologies and capabilities are implemented. The ATC system is severely out of date and is one of the largest limiting factors in current flight operations. Although participants are pessimistic about its timely implementation, the FAA's NextGen program for a future National Airspace System should help improve the efficiency of flight operations. This includes situational awareness, weather monitoring, communication, information management, optimized routing, and cleaner flight profiles like Required Navigation Performance (RNP) and Continuous Descent Approach (CDA). Working off the interview results, trade-studies were performed using an in-house flight profile simulation of a Boeing 737-300, integrating NASA legacy codes EDET and NPSS with a custom written mission performance and point-performance "Skymap" calculator. From these trade-studies, it was found that certain flight conditions affect flight operations more than others. With weather, traffic, and unforeseeable risks, flight planning is still limited by its high level of precaution. From this study, it is recommended that air carriers increase focus on defining policies like load scheduling, CG management, reduction in zero fuel weight, inclusion of performance measurement systems, and adapting to the regulations to best optimize the spirit of the requirement.. As well, air carriers should create a larger drive to implement the FAA's NextGen system and move the industry into the future. / Dissertation/Thesis / M.S. Aerospace Engineering 2014

Os simuladores de vôo têm sido uma importante ferramenta para treinamento de pilotos e análise de vôo sem ter que se desembolsar grandes quantias monetárias, economizando combustível e evitando acidentes. Conseqüentemente, a demanda por simuladores de vôo tem aumentado tanto na indústria quanto na pesquisa. Com o intuito de futuramente construir um simulador de vôo, foi desenvolvido um projeto para elaboração de um software capaz de simular uma aeronave em vôo, do ponto de vista de dinâmica de vôo. O software SIMAERO foi desenvolvido na linguagem de programação C++ e simula a dinâmica de vôo de uma aeronave. Esta simulação consiste em resolver as equações de movimento da aeronave, utilizando o modelo matemático de equações diferenciais ordinárias proposto por ETKIN & REID, et al (1996). O modelo matemático é solucionado através do método de integração numérica Runge-Kutta de 4ª ordem conforme apresentado em CONTE (1977). Como parâmetros de entrada são informadas as seguintes características da aeronave: dados geométricos, dados aerodinâmicos e derivadas de estabilidade. Os resultados das simulações são apresentados em gráficos cartesianos e gravados em arquivos. Os gráficos são úteis para que possa ser feita uma posterior análise do comportamento da aeronave. Os arquivos gravados com os resultados das simulações podem ser utilizados em alguma aplicação futura, como sinas de entrada para uma plataforma de simulação, por exemplo. Neste trabalho será descrito como o SIMAERO foi desenvolvido e ao final serão apresentados alguns resultados obtidos. / Flight simulators have been an important tool for pilots training and for flight analyses, without having to spend a high quantity of money, saving gas and prevent accidents. Because of this, the demand for flight simulators has increased both in industry and in research centers. With the objective of in future build a flight simulator, a project to develop a software that is able to simulate the dynamics of flight of a flying aircraft was developed. The SIMAERO software was developed using C++ and its principal functionality is to simulate the dynamics of flight of an aircraft. This simulation basically is the solution of the system of motion equations of the aircraft, using the mathematical model described by ETKIN & REID, et al (1996). The mathematical model is solved using the 4th order Runge-Kutta numeric integration method, as presented in CONTE (1977). For the simulation, the geometric data, the aerodynamic data, and the dimensional derivates are passed to the software as input arguments. The results of the simulations are displayed as cartesians graphics and recorded as data files. The graphics are useful for visual analyses of the aircraft behavior, and the file, with the results of the simulation, can be used as input data for ground based simulator, for example. In this work, the development of the software SIMAERO will be presented, and then some results of the simulation of one aircraft will be shown.

A área de dinâmica de aeronaves atingiu um alto nível de desenvolvimento e devido à crescente disponibilidade de computadores cada vez mais rápidos e com maior capacidade de processamento; a aplicação de técnicas numéricas de identificação nesta área também teve grande avanço. Este trabalho apresenta uma metodologia para predição de respostas de aeronaves dentro de envelopes de vôo pré-estabelecidos usando redes neurais recorrentes e uma metodologia para estimação das suas derivadas aerodinâmicas usando redes neurais feedforward. Para obter os conjuntos de dados para treinar as redes neurais, foi implementado um modelo não linear de dinâmica de vôo e simulado o comportamento de uma aeronave de combate em nove pontos de um envelope de vôo. Foram usadas as respostas simuladas correspondentes a quatro pontos para treinar a rede neural e depois disto, esta capturou satisfatoriamente a dinâmica da aeronave, identificando com grande sucesso as respostas do movimento longitudinal da aeronave por todo o envelope de vôo considerado. Após a simulação e identificação das respostas da aeronave dentro do envelope de vôo, é apresentada a resolução do problema inverso, ou seja, usando velocidades escalares e angulares da aeronave juntamente com seus dados geométricos como entradas para a rede neural feedforward, é obtido um modelo neural estimador de derivadas aerodinâmicas. Para mostrar a capacidade deste modelo neural estimador, este é aplicado na estimação das derivadas da aeronave simulada e também aplicado na estimação das derivadas aerodinâmicas da aeronave militar a jato Xavante AT-26 da Força Aérea Brasileira. Estas metodologias propostas reduzem custo de obtenção das derivadas aerodinâmicas e mostram a eficácia das redes neurais em estimar as respostas de aeronaves dentre de um envelope de vôo pré-definido. / The area of aircraft dynamics has reached a high level of development and due to the increasing availability of computers continuously faster and with bigger processing capacity, the application of numerical identification techniques in this area also had great advance. This work presents two methodologies, one for prediction of aircraft responses within a pre-established flight envelope using recurrent neural networks and another one for estimation of its aerodynamic derivatives using feedforward neural networks. To get data sets to train the neural networks, a combat aircraft flight dynamics non-linear model was implemented and simulated in nine points of the flight envelope to obtain its behavior. The simulated responses corresponding to a four points of the flight envelope were used to train the neural network and after that, it was possible to verify that this net satisfactorily captured the dynamics of the aircraft, identifying with great success the longitudinal motion responses of the aircraft at all the considered flight envelope positions. After the simulation and identification of the aircraft responses inside the flight envelope, the solution of the inverse problem is presented, i.e., using scalar and angular aircraft velocities together with its geometric data as input to the feedforward neural network, a neural estimator model of aerodynamic derivatives is obtained. In order to show the capacity of this neural estimator model, this model is applied to the estimation of the derivatives of the simulated aircraft as well as to the estimation of the aerodynamic derivatives of a brazilian air force military jet aircraft, the Xavante AT-26. These proposed methodologies reduce the cost of obtaining the aerodynamic derivatives and show the estimation effectiveness of the neural networks to estimate the responses of an aircraft inside a pre-defined flight envelope.

The development of large lightweight airframes has resulted in what used to be high frequency structural dynamics entering the low frequency range associated with an aircraft’s rigid body dynamics. This has led to the potential of adverse interactions between the aeroelastic effects and flight control, especially unwanted when incidents involving failures or extreme atmospheric disturbances occur. Moreover, the pilot’s response in such circumstances may not be reproducible in simulators and unique to the incident. The research described in this thesis describes the development of a pilot model suitable for the investigation of the effects of aeroelasticity on manual control and the study of the resulting airframe loads. After a review of the state-ofthe- art in pilot modelling an experimental approach involving desktop based pilot-in-the-loop simulation was adopted together with an optimal control based control-theoretic pilot model. The experiments allowed the investigation of manual control with a nonlinear flight control system and the derivation of parameter bounds for single-input-single-output pilot models. It was found that pilots could introduce variations of around 15 dB at the resonant frequency of the open loop pilot-vehicle-system. Sensory models suitable for the simulation of spatial disorientation effects were developed together with biomechanical models necessary to capture biodynamic feedthrough effects. A detailed derivation and method for the application of the modified optimal control pilot model, used to generate pilot control action, has also been shown in the contexts of pilot-model-in-the-loop simulations of scenarios involving an aileron failure and a gust encounter. It was found that manual control action particularly exacerbated horizontal tailplane internal loads relative to the limit loads envelope. Although comparisons with digital flight data recordings of an actual gust encounter showed a satisfactory reproduction and highlighted the adverse affects of fuselage flexibility on manual control, it also pointed towards the need for more incident data to validate such simulations.

This thesis explores the possibility of estimating the outcome of a flight ticket fare comparison search, also called flight meta search, before it has been performed, as being able to do thiscould be highly useful in improving the flight meta search technology used today. The algorithm explored in this thesis is a distance weighted k-nearest neighbour, where the distance metric is a linear equation with sixteen features of first degree extracted from the input of the search. It is found that while the approach may have potential, the distance metric used in this thesis isnot sufficient to capture the similarities needed, and the end algorithm performs only slightly better than random. At the end of this thesis a series of possible further improvements are presented, that could potentially help improve the performance of the algorithm to a level that would be more useful.

Please read the abstract in the section 00front of this document / Dissertation (MA (Research Psychology))--University of Pretoria, 2005. / Psychology / unrestricted

Today, the air transport industry has become an essential element of global society by its great contributions to the wide exchanges of cultures/people and to the rapid growth in the world economy. However, on the other hand, the adverse impacts on the environment caused by air transport, such as air pollution, noise and climate change, are drawing, increasingly, growing public concern. In order to address the steady growth in air-travel demand in the next decades through an environmentally-friendly way and realise the ACARE 2020 environmental goals, The Clean Sky programme has been launched by European Union over the period 2008 – 2013. The project research, described in this thesis and sponsored by the Clean Sky programme, aims at evaluating the feasibility of reducing the environmental impact of commercial aviation through the introduction of changes in the aircraft operational rules and procedures, as well as the application of the new-generation propfan (open rotor) engine, based on flight trajectory multidisciplinary optimisation and analysis of commercial aircraft. In order to accomplish the above research objectives, a complete methodology to achieve and realise optimum flight trajectories has been initially proposed. Then, 12 component-level models which function as simulating different disciplines, such as aircraft performance, engine performance, engine gaseous emission, and flight noise, have been developed or selected/adopted. Further, nine system-level integration and optimisation models were built. These system-level models simulate flights from Amsterdam Schiphol airport in the Netherlands to Munich airport in Germany flown by different types of aircraft through different flight phases with different optimisation objectives. Finally, detailed investigations into the flight trajectory optimisations were performed, extensive optimisation results were achieved and corresponding description, analysis and comparisons were provided. The main contributions of this work to knowledge broadly comprise the following: 1) the further development regarding the methodology of flight trajectory multidisciplinary optimisation; 2) previous work on aircraft trajectory optimisation has often considered fixed objectives over the complete flight trajectory. This research focused on representative flight phases of a flight mission with different optimisation objectives, namely, noise impact and fuel burn during the departure phase; fuel burn and flight time during en route phase; and noise impact and NOx emission during the arrival phase; 3) this research has extended the current flight trajectory optimisations to turboprop and propfan equipped aircraft. As a result, a relative complete 2D flight trajectory multidisciplinary optimisation spectrum, spanned by primary commercial aircraft types, primary flight phases and primary optimisation objectives of interest, has been built. Although encouraging progress have been achieved, this project research, as with any other research activity, is also only ‘on the way’ rather than coming to the ‘end’ point. There are still many aspects which can be improved further and there is still much new research and exploration which can be investigated further. All these have also been suggested in this thesis.

Flight across the North Atlantic is a routine process now, with thousands of flights carrying millions of passengers between Europe and North America every year quickly, safely, and affordably. By some measures it remains the busiest international flight corridor in the world and the most profitable for airlines. Yet there were no planes capable of making the flight a mere century ago. Aviation underwent a period of rapid development and expansion during the twentieth century that transformed the North Atlantic from a barrier into a central corridor in the global air network. This dissertation examines the development of civil aviation on the North Atlantic from 1919 to 1970, focusing on political, economic, and technological factors. Transatlantic flight was a focus of aviation but the earliest planes lacked the range needed to make the crossing. Technological improvements let pioneering aviators cross the ocean by 1919, proving that it was possible though difficult without further advances. Infrastructure also needed to be further developed since the North Atlantic was a hostile environment, with bad weather and limited facilities for aircraft in emergencies. Until 1945, the governments of the North Atlantic region thoroughly explored, studied, and built the infrastructure to make regular transatlantic possible. Postwar, governments supported their airlines through further infrastructural improvements, subsidies, by funding aeronautics, and by complex negotiations with foreign countries to open the skies to passenger travel. By 1970, transatlantic flight was a routine endeavour enjoyed by the masses and supported by systems invisible to the average traveler.

The control of multiple unmanned aerial vehicles (UAVs) in a swarm or cooperative team scenario has been a topic of great interest for well over a decade, growing steadily with the advancements in UAV technologies. In the academic community, a majority of the studies conducted rely on simulation to test developed control strategies, with only a few institutions known to have nurtured the infrastructure required to propel multiple UAV control studies beyond simulation and into experimental testing. With the Cal Poly UAV FLOC Project, such an infrastructure was created, paving the way for future experimentation with multiple UAV control systems. The control system architecture presented was built on concepts developed in previous work by Cal Poly faculty and graduate students. An outer-loop formation flight controller based on a virtual waypoint implementation of potential function guidance was developed for use on an embedded microcontroller. A commercially-available autopilot system, designed for fully autonomous waypoint navigation utilizing low cost hardware and open source software, was modified to include the formation flight controller and an inter-UAV communication network. A hardware-in-the-loop (HIL) simulation was set up for multiple UAV testing and was utilized to verify the functionality of the modified autopilot system. HIL simulation results demonstrated leader-follower formation convergence to 15 meters as well as formation flight with three UAVs. Several sets of flight tests were conducted, demonstrating a successful leader-follower formation, but with relative distance convergence only reaching a steady state value of approximately 35 +/- 5 meters away from the leader.