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Método exergético para concepção e avaliação de desempenho de sistemas aeronáuticos.; Exergy method for conception and performance evaluation of aircraft systems.

Gandolfi, Ricardo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 06/08/2010 PT
Relevância na Pesquisa
37.18%
A tendência da indústria aeronáutica comercial é o desenvolvimento de aviões mais eficientes em termos de consumo de combustível e custos operacionais diretos. No que diz respeito ao consumo de combustível, algumas estratégias da indústria aeronáutica são o uso de uma aerodinâmica mais eficiente, materiais mais leves e motores e sistemas mais eficientes. O motor turbo jato convencional fornece potência elétrica para os sistemas de cabine (luzes, entretenimento, cozinha) e aviônicos, potência hidráulica para os sistemas de controle de vôo e potência pneumática para proteção contra formação de gelo e unidade de controle ambiental. Motores mais eficientes e diferentes tipos de arquiteturas de sistemas, como os sistemas mais elétricos, são promessas para reduzir o consumo de combustível. A fim de comparar os processos energéticos das arquiteturas de sistemas e motor numa mesma base, a exergia é o verdadeiro valor termodinâmico que deve ser utilizada como ferramenta de decisão para projeto de sistemas, motores e aeronaves, assim como parâmetro de otimização. Trabalhos de outros autores focaram apenas em redução da exergia destruída e nenhum trabalho apresentou um método harmonizador que consolide os parâmetros já existentes e crie outros parâmetros comparativos entre sistemas. Este trabalho propõe um método baseado em análise exergética para concepção e avaliação de sistemas aeronáuticos...

OMPP para projeto conceitual de aeronaves, baseado em heurísticas evolucionárias e de tomadas de decisões; OMPP for conceptual design of aircraft based on evolutionary heuristics and decision making

Abdalla, Alvaro Martins
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 30/10/2009 PT
Relevância na Pesquisa
37.07%
Este trabalho consiste no desenvolvimento de uma metodologia de otimização multidisciplinar de projeto conceitual de aeronaves. O conceito de aeronave otimizada tem como base o estudo evolutivo de características das categorias imediatas àquela que se propõe. Como estudo de caso, foi otimizada uma aeronave de treinamento militar que faça a correta transição entre as fases de treinamento básico e avançado. Para o estabelecimento dos parâmetros conceituais esse trabalho integra técnicas de entropia estatística, desdobramento da função de qualidade (QFD), aritmética fuzzy e algoritmo genético (GA) à aplicação de otimização multidisciplinar ponderada de projeto (OMPP) como metodologia de projeto conceitual de aeronaves. Essa metodologia reduz o tempo e o custo de projeto quando comparada com as técnicas tradicionais existentes.; This work is concerned with the development of a methodology for multidisciplinary optimization of the aircraft conceptual design. The aircraft conceptual design optimization was based on the evolutionary simulation of the aircraft characteristics outlined by a QFD/Fuzzy arithmetic approach where the candidates in the Pareto front are selected within categories close to the target proposed. As a test case a military trainer aircraft was designed target to perform the proper transition from basic to advanced training. The methodology for conceptual aircraft design optimization implemented in this work consisted on the integration of techniques such statistical entropy...

Atividade de montagem estrutural de aeronaves e fatores associados à capacidade para o trabalho e fadiga; Aircraft structural assembly and factors associated with work ability and fatigue

Menegon, Fabrício Augusto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 02/05/2011 PT
Relevância na Pesquisa
37.13%
Objetivo: analisar o trabalho de montagem estrutural de aeronaves e os fatores associados à capacidade para o trabalho e a fadiga, relacionados às cargas de trabalho, condições de vida e estilos de vida, entre trabalhadores da indústria aeronáutica brasileira. Método: foram avaliados 552 operadores de montagem estrutural de aeronaves. Os participantes responderam a questionários padronizados sobre: condições de vida, condições de trabalho, hábitos e estilos de vida, sono, sintomas ósteomusculares, capacidade para o trabalho (ICT) e fadiga. Foram realizadas observações das tarefas de trabalho de montagem estrutural de aeronaves para a elaboração de uma descrição do trabalho e avaliação das demandas de trabalho. Foram elaboradas descrições detalhadas das tarefas observadas e das demandas de trabalho identificadas para a composição de uma análise da situação de trabalho de montagem estrutural de aeronaves. Os dados coletados dos questionários foram submetidos a análises de regressão logística univariada e multivariada. Foram obtidos os valores das razões de chance (OR), brutos e ajustados, e seus respectivos intervalos de confiança (IC 95 por cento ). O nível de significância estabelecido para as análises foi de p<0...

Entre a vivência do conforto e do desconforto em cabines de aeronaves: uma abordagem baseada na atividade.; Living experience between comfort and discomfort in an aircraft cabin: an approach based on activity.

Ciaccia, Flavia Renata Dantas Alves Silva
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 10/12/2012 PT
Relevância na Pesquisa
37.03%
Nos últimos anos, inúmeros trabalhos têm investigado como avaliar a percepção de conforto e desconforto no transporte aéreo. A literatura mostra que o conforto é um construto de natureza subjetiva, de difícil mensuração e, por este motivo, a avaliação de aspectos de desconforto é sugerida em alguns estudos. O objetivo geral desta pesquisa foi aprimorar os métodos de análise do conforto e do desconforto vivenciado pelo passageiro ao considerar as atividades realizadas durante um voo típico, contribuindo com o projeto de poltrona e de cabine de aeronaves. Para tal, este estudo propõe um método dividido em três fases: mapeamento de pressão de posturas estáticas, mapeamento contínuo de pressão e mapeamento de posturas típicas. O intuito da primeira fase foi identificar as contribuições e limitações dos métodos e técnicas descritos na literatura por meio de um experimento utilizando mapeamento de pressão de interface entre o ocupante e a poltrona em de posturas estáticas e um questionário de avaliação da poltrona. A segunda fase analisou as atividades de repousar e ler em um simulador que representa o interior de uma aeronave, com o apoio da técnica de medição contínua de pressão de interface em conjunto com observação de pesquisadores e relato pós-experimento. Após a realização dos ensaios...

Conforto e desconforto da cor da iluminação em uma cabine de aeronave: uma análise experimental.; Comfort and discomfort associated with the color of illumination of cabin of aircraft: an experimental analysis.

Vertamatti, Egidio
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 14/01/2014 PT
Relevância na Pesquisa
37.03%
Em uma viagem de avião os passageiros ficam de 1 a 12 horas em determinada localização, na maior parte do tempo sentados, com limitações nos ajustes de seus assentos, expostos a ruídos, vibrações mecânicas, temperaturas desconfortáveis, condições que podem levá-los a um processo de estresse em função do desconforto a que estão sujeitos. Outro fator importante para a sensação de desconforto é a qualidade e a cor da iluminação do interior da aeronave. A cor de uma iluminação tem influência no estado de humor das pessoas, que pode afetar de maneira positiva ou negativa o seu estado emocional. Com o avanço tecnológico e a invenção LED (Light Emitting Diode, Diodo Emissor de Luz) pode-se criar uma iluminação no interior da cabine, com cores que podem ser alteradas facilmente e dessa maneira influenciar o estado emocional dos passageiros. O objetivo da presente pesquisa é determinar a sensação de conforto/desconforto causada pela cor da iluminação em uma cabine de aeronave. Foi realizada uma pesquisa bibliográfica para se obter dados sobre a influência das cores no estado emocional das pessoas. Também foi pesquisado o mecanismo de funcionamento do sistema visual humano e como percebemos as informações visuais. A pesquisa foi realizada com uma população representativa de passageiros de aeronaves. Fez-se um levantamento quantitativo de aspectos subjetivos da percepção da qualidade do ambiente em função da cor da iluminação...

Medições de ruído aeronáutico dentro da área II do Plano Específico de Zoneamento de Ruído do Aeroporto Salgado Filho, Porto Alegre, RS; Aircraft noise measurement within Área II of the Specific Noise Zoning Plan for Salgado Filho Airport

Nabinger, Luciano Baldino
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.21%
Este trabalho expõe e analisa resultados de medições acústicas de aeronaves; realizadas dentro da Área II do Plano Específico de Zoneamento de Ruído- PEZR. O plano restringe o uso do solo em decorrência das emissões sonoras, oriundas da movimentação das aeronaves para cada um dos 66 aeroportos brasileiros administrados pela INFRAERO. As medições acústicas foram realizadas entre segunda e sexta feira, no período diurno (entre 7 e 22 horas) registrando um total de 697 eventos sonoros aeronáuticos, gerados por 62 modelos diferentes de aeronaves. Os procedimentos de aquisição de dados atendem a ISO 3891 (Procedimentos para descrever o ruído aeronáutico percebido no solo), e o Guia de Monitoramento de Ruído Aeronáutico, Francês, elaborado pelo Serviço Técnico da Navegação Aérea- STNA. Com o uso de softwares, discriminaram-se os Eventos Aeronáuticos (passagem de aviões) do Ruído de Fundo. Assim, quantificou-se, com razoável precisão, o impacto sonoro causado por ruído aeronáutico e definiram-se os índices: L50 (Ruído de Fundo) e o índice L1 (Eventos Aeronáuticos). São apresentados os níveis de ruído (SEL, LMáx, LMín e Leq em dB (A)) e as análises espectrais (de 10 a 20.000 Hz, relacionados às curvas NCB...

16.885J / ESD.35J Aircraft Systems Engineering, Fall 2003; Aircraft Systems Engineering

Hansman, Robert John; Liebeck, Robert H; Murman, Earll M., 1942-; Haggerty, Allen C
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
EN-US
Relevância na Pesquisa
37.25%
Subject addresses a holistic systems engineering approach for aircraft development. Focuses on the conceptual phase of product definition during which all aspects relevant to a new or derivative aircraft must be considered. These include technical, economic, market, environmental, regulatory, legal, manufacturing, and societal factors. Subject centers on a realistic aircraft system case study and includes a number of lectures from industry and government. Past examples included the Very Large Transport Aircraft and a Supersonic Business Jet. Subject identifies the critical system level issues and analyzes them in depth via student team projects and individual assignments. The overall goal of the semester is to produce a business plan and aircraft level system specifications document which can serve as an independent assessment of a current candidate aircraft system. From the course home page: Course Description Aircraft are complex products comprised of many subsystems which must meet demanding customer and operational lifecycle value requirements. This course adopts a holistic view of the aircraft as a system, covering: basic systems engineering; cost and weight estimation; basic aircraft performance; safety and reliability; lifecycle topics; aircraft subsystems; risk analysis and management; and system realization. Small student teams "retrospectively analyze" an existing aircraft covering: key design drivers and decisions; aircraft attributes and subsystems; and operational experience. Finally...

Resolution of Conflicts Involving Many Aircraft via Semidefinite Programming

Frazzoli, E.; Mao, Z. H.; Oh, J. H.; Feron, E.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Relatório
EN_US
Relevância na Pesquisa
37.13%
Aircraft conflict detection and resolution is currently attracting the interest of many air transportation service providers and is concerned with the following question: Given a set of airborne aircraft and their intended trajectories, what control strategy should be followed by the pilots and the air traffic service provider to prevent the aircraft from coming too close to each other? This paper addresses this problem by presenting a distributed air-ground architecture, whereby each aircraft proposes its desired heading while a centralized air traffic control architecture resolves any conflict arising between the aircraft involved in the conflict, while minimizing the deviation between desired and conflict-free heading for each aircraft. The resolution architecture relies on a combination of convex programming and randomized searches: It is shown that a version of the planar, multi-aircraft conflict resolution problem that accounts for all possible crossing patterns among aircraft might be recast as a nonconvex, quadratically constrained quadratic program. For this type of problem, there exist efficient numerical relaxations, based on semidefinite programming, that provide lower bounds on the best achievable objective. These relaxations also lead to a random search technique to compute feasible...

Thermally induced flows and ventilation within an aircraft wing leading edge compartment

Moore, Daithí
Fonte: University of Limerick Publicador: University of Limerick
Tipo: info:eu-repo/semantics/doctoralThesis; all_ul_research; ul_published_reviewed; ul_theses_dissertations
ENG
Relevância na Pesquisa
37.07%
peer-reviewed; Modern day airliners are subjected to a wide range of environmental conditions when operational across the globe. In order to ensure reliable aircraft performance and avoid thermal failure of heat sensitive components, consideration must be given to the wide range of temperatures that the aircraft will encounter when designing aircraft internal enclosures. This thesis presents an investigation into the fluid flow and heat transfer within an aircraft wing leading edge compartment due to solar loading and the presence of an internal bleed duct. A detailed experimental investigation into the thermal distribution, bleed duct heat transfer and flow structure was performed for 1 105 < Grasho f No: < 4 105 in a representative wing leading edge enclosure constructed for this purpose. Temperature measurements were recorded along the interior surfaces along with the internal air temperature in the cavity. Particle Image Velocimetery (PIV) was used to quantify the flowfield present in the leading edge. There were three main aspects to this thesis: The first was to characterise the enclosure conditions and bleed duct heat transfer within the sealed leading edge. This was performed firstly to gain an understanding of the heat transfer characteristics within the leading edge and secondly to use as a comparison for when ventilation was introduced. It was observed that the confining effect of the enclosure was only evident at the higher Gr range investigated...

Aircraft crown compartment thermal management: the influence of internal heat dissipating elements

Butler, Colin
Fonte: University of Limerick Publicador: University of Limerick
Tipo: info:eu-repo/semantics/doctoralThesis; all_ul_research; ul_published_reviewed; ul_theses_dissertations
ENG
Relevância na Pesquisa
37.07%
peer-reviewed; The content of this thesis describes the interaction of internal heat dissipating elements with their heated enclosure with the applied case of a crown compartment in a single aisle commercial aircraft. The crown compartment is defined as the confined area between the passenger cabin and the upper external fuselage. Aircraft compartments are subject to a wide variety of boundary conditions during operation which leads to the setting up of highly complex internal thermal environments. These compartments require strict thermal management to ensure safe and reliable operation of the installed systems. The work conducted firstly examines the fundamental fluid flow and natural convection heat transfer inside a differentially heated square cavity with a centrally located heated horizontal cylinder. There is a distinct lack of information available in literature which focuses on the change in heat transfer experienced by the cylinder due to the interaction with the enclosure. An increase in the cylinder heat transfer is observed due to this interaction. Experimental thermocouple and PIV measurements confirmed the presence of a transition process whereby the flow transitions from being dominated by the temperature difference across the cavity to that dominated by the temperature difference due to the cylinder for the range 2 ×104 < Racyl < 8 ×104. A similar investigation was then conducted for the crown compartment. A study of the unpopulated case...

CFD modeling of airflows and contaminant transport in an aircraft cabin

Zhang, J.; Wang, Y.; Tian, Z.; Lu, T.F.; Awadalla, M.
Fonte: The Modelling and Simulation Society of Aust & NZ; Australia Publicador: The Modelling and Simulation Society of Aust & NZ; Australia
Tipo: Conference paper
Publicado em //2013 EN
Relevância na Pesquisa
37.13%
There are an increasing number of passengers undertaking air travels on commercial airliners throughout the world annually. During the flights, passengers are possibly exposed to different contaminants such as bacterial and CO2 from other passengers. As airliner cabins have high occupant density and flights can last from 1 to 20 hours, transport of contaminant could have serious impact on both passengers and aircraft crew. It is important to understand airflows and contaminant transport inside the aircraft cabin in order to reduce the negative impacts. Current aircraft cabin airflows can be analyzed by two different methods, experimental measurements and computer modeling. With the rapid increase in computer power, computer modeling is becoming more popular in study of aircraft cabin flows. Computational fluid dynamics (CFD) is the most used modeling approach since it is relatively inexpensive, fixable and able to obtain high level resolution results. The main scope of this research is to develop a frame work to simulate airflows and trace contaminant transport in an aircraft cabin using CFD. The predicted airflows and contaminant concentration are then used to train an Artificial Intelligent (AI) system. This trained AI system will be able to trace back the possible source of the contaminant once the transmission of contaminant happens in the aircraft cabin...

Summary of Research 2001, Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS)

Faculty of the Naval Postgraduate School, Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS)
Fonte: Office of the Associate Provost and Dean of Research, Naval Postgraduate School. Publicador: Office of the Associate Provost and Dean of Research, Naval Postgraduate School.
Tipo: Relatório
EN_US
Relevância na Pesquisa
46.83%
The views expressed in this report are those of the author and do not reflect the official policy or position of the Department of Defense or U.S. Government.; This report contains project summaries of the research projects in the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS). A list of recent publications is also included, which consists of conference presentations and publications, books, contributions to books, published journal papers, and technical reports. Thesis abstracts of students advised by faculty in the Department are also included.

UNOLS now oversees research aircraft facilities for ocean science

Bane, John M.; Bluth, Robert; Flagg, Charles; Jonsson, Haflidi; Melville, W. Kendall; Prince, Mike; Riemer, Daniel
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
37.1%
In recognition of the increasing importance and value of aircraft as observational platforms in oceanographic research, the University National Oceanographic Laboratory System (UNOLS) has established the Scientific Committee for Oceanographic Aircraft Research (SCOAR).SCOAR aims to establish procedures for research aircraft that follow the present UNOLS practices for research vessel use, with the goal of making it understandable, and easy, and thus desirable, for oceanographic scientists to utilize research aircraft more. For consistency with the operation of UNOLS ships, this will require UNOLS to designate appropriate research aircraft operating organizations to be National Oceanographic Aircraft Facilities (NOAFs), essentially like institutions that operate one or more UNOLS ships. UNOLS presently has one designated NOAF the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) at the Naval Postgraduate School, in Monterey, California.

An analysis of retaining or replacing Air Force command and control aircraft

Austin, Joe J.; Lynch, Horace R.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Formato: xiv, 97 p. : col. ill.; 28 cm.
Relevância na Pesquisa
37.15%
MBA Professional Report; This MBA Project's objective was to analyze information available to determine if the Air Force should retain or replace its command and control aircraft. To accomplish the objective, research pertaining to the Air Force's aircraft and requirements was conducted along with analyzing new aircraft available that can be modified for current and future missions. The project provides background information about the various missions command and control aircraft perform, as well as the importance of maintaining the capability. Current command and control aircraft, as well as potential aircraft that can replace the existing command and control aircraft, were researched to determine the cost and performance specifications. The current and potential aircraft were analyzed, and factors other than costs were also examined. The challenges facing the Air Force's recapitalization efforts were presented. These challenges include cost and funding priorities; schedule and production lead times; personnel; and facilities and support equipment. The completed product identifies if the Air Force should retain or replace command and control aircraft. Additional areas for further research were listed which could provide more information once more data becomes available to compare with the project findings.

Deciphering chinese strategic deception: the middle kingdom's first aircraft carrier

Kong, Eu Yen; Yu, Kuei-Lin
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Relevância na Pesquisa
37.07%
Approved for public release; distribution is unlimited; The thesis examines Chinas employment of strategic deception in the acquisition and development of its first aircraft carrier the Liaoning in 2012. By examining Chinas national goals, strategy and propensity to employ deception, this thesis aims to: 1. Explain how Chinas national goals and strategy drove it to develop an aircraft carrier. 2. Explain the aircraft carriers role in Chinas maritime strategy. 3. Explain how China employed deception in the acquisition and development of the aircraft carrier. 4. Assess the implications of Chinas use of strategic deception in developing its first aircraft carrier. 5. Assess the future role of Chinas first aircraft carrier.; Major, Republic of Singapore Navy; Lieutenant Colonel, Republic of China Marine Corps (Taiwan)

Upgradable operational availability forecasting tool for the U.S. Navy P-3 replacement aircraft

Margolis, Michael C.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xviii, 110 p. : ill. (some col.) ;
Relevância na Pesquisa
37.07%
Approved for public release; distribution in unlimited.; The P-3 Orion maritime aircraft has been the U.S. Navy's primary maritime patrol aircraft since its fleet introduction in 1962. Naval Aviation Systems Command (NAVAIR) has determined that the P-3 fleet has sufficiently aged to warrant a replacement. The replacement aircraft is currently undergoing the conceptual phase of development and it is during this period that NAVAIR is interested in evaluating the trade-off between operational availability and the associated cost to achieve this operational availability. This thesis developed a simulation tool that was used to investigate relationships that affect cost and operational availability of the new (notional) aircraft on a deployment. The simulation tool was exercised for select scenarios in order to gain insights into the value of investing funds in additional aircraft versus the value of investing funds in increased component reliability. The simulation was developed to be very flexible and extensible, enhancing its value for future analyses. Required data inputs into the simulation tool are formatted utilizing a new technology called Extensible Markup Language (XML) which facilitates use of the data in nearly all computer software packages. The model is robust in nature and can be applied to a wide variety of aircraft.; Captain...

Optimally scheduling EA-6B depot maintenance and aircraft modification kit procurement

Baker, Rosser O., Jr.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xii, 56 p.
EN_US
Relevância na Pesquisa
37.13%
Approved for public release, distribution is unlimited; The Department of the Navy maintains a fleet of 124 EA-6B aircraft, the only tactical electronic warfare aircraft in the Department of Defense inventory. Already 30 years old and not to be retired until 2015, the EA-6B requries depot maintenance services to remain combat ready. EA-6B aircraft undergo standard depot level maintenance (SDLM) about every eight years. In addition to SDLM, depots must complete 72 wing center section replacement services and over 175 major aircraft modification services by 2010. Navy regulations govern when each EA-6B is eligible for each service; these rules are flexible enough to allow more induction schedules than can be evaluated manually in a reasonable amount of time. Because each service keeps an aircraft at the depot for six to 14 months and performing multiple services together requires less time than performing services independently, services should be combined whenever possible. This thesis introduces DMAAP (Depot Maintenance And Acquisition Planner); a prototypic optimization based decision support tool to assist in scheduling EA-6B depot level maintenance services and major aircraft modification kit acquisition. DMAAP produces a Master Plan (induction schedule) providing a monthly schedule for the first six years...

An analysis of impending aircraft generational change in the RAAF

Abrahams, Asher
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Relatório
Relevância na Pesquisa
37.23%
This research paper is an analysis of impending aircraft generational change in the Royal Australian Air Force (RAAF) that analyses the capability difference between Fourth and Fifth generation fighter aircraft within the Australian context. This analysis provides a working definition of fighter aircraft generations which forms the foundation of an investigation into the potential acquisition of Fifth Generation fighter aircraft by the RAAF . The definition provides an educated foundation for the continued public discourse on fighter generations and generational change in the RAAF, a subject that is much discussed but relatively misunderstood. This paper is designed to provide those without a military background- the general public- with an easily comprehensible education piece covering this complex topic. As an analysis of impending generational change, this paper explores the concept that offensive air power is only as effective as the fighter aircraft that project it. Additionally, this paper invest igates the operational requirements for fighter aircraft in contemporary environments. Finally, this paper explores the implications of generational change on the RAAFs future, before providing an overall conclusion to this broad research topic. This paper recognises that the first generation of fighter aircraft occurred with the advent of jet engine technology at the end of the World War II...

Longitudinal dynamic modeling and control of powered parachute aircraft

Chambers, John
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
37.1%
Powered parachutes (PPC) represent a very unique class of aircraft which have thus far seen limited use beyond recreational flight. Their slow flight and large payload characteristics make them a practical platform for applications such as aerial spraying and surveillance. The portability of the units when not airborne, fast transition to flight readiness, inherent stability, and simplicity of control enhance their appeal for use as Unmanned Aerial Vehicles (UAV). The aircraft fly using only three control inputs consisting of two steering lines and a throttle for control of climb and descent. One of the more interesting characteristics that distinguish PPC from conventional aircraft is the pendulum stability which is a consequence of suspending the majority of the aircraft weight so far from the wing surface and which introduces an appreciable amount of lag into the system. Another interesting phenomenon is their speed stability which causes the aircraft to fly at a relatively constant speed whether it is climbing, descending, or flying straight-and-level. The current study seeks to examine the effects of throttle on the longitudinal dynamics of PPC, using a small-scale aircraft. A dynamic model has been derived using analytical methods and computer-simulated in MATLAB and Simulink...

Center-of-gravity estimation of an aircraft solely using traditional aircraft measurement sensors

Komendat, Andrew
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
37.07%
In this work, a novel algorithm for estimating aircraft center-of-gravity location based solely on traditional aircraft measurements is investigated. The algorithm uses known physics-based kinematic relationships between aircraft states for the estimation process and requires only traditional sensor measurements typically employed by aircraft. Three models are used in the algorithm development: one based on using attitude measurements, the second based on using air data measurements, and the third based on using navigation type measurements. Estimation of the aircraft's aerodynamic parameters is not required in the new approach. However, sensor error such as accelerometer bias effects are estimated in the algorithm process. A high performance aircraft simulation model is used to test the feasibility of the approach. In all individual and combined model simulations center-of-gravity was estimated with a high degree of accuracy. In addition, flight test data is used to verify the effectiveness of the algorithm in localizing the center-of-gravity successfully.