There are many challenges facing the aerospace industry that can be addressed with new concepts, technologies, and materials. However, current design methods make it difficult to include these new ideas early in the design of aircraft. This is especially true in the structures discipline, which often uses weight-based methods based upon statistical regressions of historical data. A way to address this is to use physics-based structural analysis and design to create more detailed structural data. Thus, the overall research objective of this dissertation is to develop a physics-based structural analysis method to incorporate new concepts, technologies, and materials into the conceptual design phase. The design space of physics-based structural design problem is characterized as highly multimodal with numerous discontinuities; thus, a large number of alternatives must be explored. Current physics-based structural design methods tend to use high fidelity modeling and analysis tools that are computationally expensive. This dissertation proposes a modeling & simulation environment based on classical structural analysis methods. Using classical structural analysis will enable increased exploration of the design space by reducing the overall run time necessary to evaluate one alternative. The use of physics-based structural optimization using classical structural analysis is tested through experimentation. First the underlying hypotheses are tested in a canonical example by comparing different optimization algorithms ability to locate a global optimum identified through design space exploration. Then the proposed method is compared to a method based on higher fidelity finite element analysis as well as a method based on weight-based empirical data to validate the overall research objective.

The principal objective of this thesis is to propose a Contrail forecasting Service for Aviation(ConSA) and a ConSA client to demonstrate the service. The subject is motivated by the fact that Contrails have a very harmful effect on the environment and it has been researched thoroughly by scientists. But still we do not have an infrastructure to include these researches in the Aviation industry. This thesis has been conducted at Airbus Defence and Space, Friedrichshafen, Germany. The first part of the thesis investigates the existence of contrails. The object of interest i.e. Contrails is caused by the passage of aeroplanes in ice-saturated areas. The algorithm which is used by the service is a part of the research conducted by Prof. Dr. Ulrich Schumann. The input dataset provided by Meteo France is a 4D weather cube. The algorithm computes a threshold temperature and ice supersaturation condition. When both of these conditions are satisfied Contrail formation is certain. In the second part we explain the architecture and solution used i.e. OGC (Open Geospatial Consortium) and LuciadLightspeed to develop Web Services to deploy contrail forecasting methods. Such an architecture fast forwards and eases the task of developer by having inbuilt methods and interfaces. The OGC web services infrastructure has defined web feature service and client interface which ease development of geoinformatics solutions.We also use certain standards like WXXM for exchange of contrail information which will be stated in this chapter. The third part is about the detailed implementation of the ConSA service and client. In this chapter we explain the service and client with uml diagrams to clarify the development concepts. The final part of the thesis explains the results of ConSA service and client, operational benefits of ConSA and concludes the thesis.

The specific purpose of this investigation is to compile selected case problems for use in teaching human relations by the case method. This investigation will include those case situations that involve many of the factors that cause differences of opinion and friction between individuals or groups. The cases selected are limited to those that actually became the subject of a grievance in the aircraft industry of the Dallas-Fort Worth area of North Texas.

D.Com. / When low cost carriers are introduced into domestic or regional scheduled air transport markets, the effects tend to be profound. In most markets where they have been introduced, lower prices have tended to lead to the stimulation of demand. As the scope of the market increases, so too does the number of entrants in the market, resulting not only in higher levels of competition but also lower prices and services. The success of the low cost model is indicated by the uptake in the air transport markets, where low cost carriers sometimes account for as much as 50% of the total air traffic movements. The presence of the low cost carriers is not necessarily a guarantee of success and the market failure rates tend to be high...

O modelo de avaliação da camada limite dinâmica e térmica foi implementado, no presente trabalho, em um código numérico para o cálculo do coeficiente de transferência de calor convectivo sobre aerofólios de uso aeronáutico com formação de gelo. Foram considerados, no modelo da camada limite turbulenta, os efeitos da rugosidade equivalente do grão de areia ks, e transição entre o regime laminar e turbulento foi avaliada por dois modelos, um abrupto e um suave. Para a transição suave foi utilizada uma função intermitência proposta por (ABU-GHANNAM; SHAW, 1980). O código desenvolvido neste trabalho foi acoplado aos módulos do código ONERA com o objetivo de simular as formas de gelo em aerofólios para diversas condições de escoamento do ar com conteúdo de água. As formas de gelo obtidas foram comparadas com dados experimentais de Shine Bond (1994) e com resultados de simulações dos códigos LEWICE, TRAJICE e ONERA (KIND, 2001). Os resultados das simulações do presente trabalho apresentaram boa semelhança com os resultados dos outros códigos. A simulação da previsão de formas de gelo do tipo Glaze, do presente trabalho e dos outros códigos, resultou em formas de gelo de espessura e volume menores que as formas experimentais. Foi verificado que uma previsão adequada do coeficiente de transferência de calor convectivo afeta a simulação das formas deste tipo de gelo. Um caso de Kind (2001) foi utilizado para avaliar os efeitos dos parâmetros da camada limite dinâmica e térmica na formação de gelo em aerofólios. Verificou-se que a posição do início da transição do regime laminar para o turbulento, o comprimento d a transição e o valor da rugosidade afetam a forma, a espessura e o volume do gelo, e que estes parâmetros podem ser utilizados para ajustes dos modelos de camada limite para melhores previsões de formas de gelo do tipo Glaze. / The model to evaluate the momentum and thermal boundary layer was implemented, in the present work, in a numerical module to calculate the convective heat transfer coecient over aeronautical airfoils with ice accretion. It was considered, in the turbulent boundary layer model, the eects of the equivalent sand grain roughness ks , and the laminar to turbulent transition was evaluated with two models, the abrupt and the smooth one. The smooth transition model used an intermittency function proposed by (ABU-GHANNAM; SHAW, 1980). The module developed in this work was integrated with the modules of the code ONERA in order to simulate the airfoil icing shapes for several air stream with water droplets condition. The ice shapes obtained was compared with experimental data of Shin e Bond (1994) and with simulation results for the codes LEWICE, TRAJICE e ONERA (KIND, 2001). The results of the simulations for the present work showed a good similarity with the other codes results. The Glaze icing shapes simulation, in the present work and in the other codes, resulted in icing shapes with thickness and volumes lesser than the experimental shapes. It was noted that a reasonable prediction of the convective heat transfer coecient aects the simulation of this type of ice shape. One case of Kind (2001) was used to evaluate the eects of the momentum and thermal boundary layer for the icing accreations in the airfoil. It was noted the onset position, the lenght of the laminar-turbulent transition, and the sand grain roughness value aects the icing shape, thickness and volume and this parameters might be used to adjust the boundary layer models in order to get better predictions of Glaze icing shapes.

Unmanned Aerial Systems (UAS) are a growing asset. Currently UAS are on the cutting edge with resources being spent developing the capabilities mostly for military use. This project is intended to create a system for non-defense customers. Specifically, the Operationally Responsive Aircraft (ORA) will appeal to academic institutions, individual consumers, future customers new to the UAS industry, as well as anybody trying to get airtime for custom sensors. The system developed in this project utilizes dual aluminum external payload bays attached to a ParkZone Radian aircraft. Each external payload bay can contain approximately 500 $\text{cm}^3$, with a height and width limit of 4.1 cm and 11.0 cm respectively. The custom sensors must weigh less than or equal to 3.2 lbs combined. The external payload bays were designed to hold an imaging payload which produces a composite map of the land surveyed. The system incorporates an Arduino Uno, SD Shield, as well as a CMOS camera and board. The processor saves individual images to an SD card. Once the aircraft has landed, the operator combines the images with Microsoft Research Image Composite Editor to create the composite map. This imaging payload has a NIIRS value of 4.0 +/- 0.4, which is equivalent to identifying a basketball court within a residential environment.

Aus der Einleitung: "Am späten Nachmittag des 14. März 1931 versammelten sich in Groß-Kühnau bei Dessau zahlreiche deutsche und amerikanische Wissenschaftler, um einem spektakulären Ereignis beizuwohnen. Geladen hatten der ehemalige Junkers- Ingenieur Johannes Winkler und dessen Mäzen, der böhmische Hutfabrikant Hugo Hückel, denen vor den Augen eines staunenden Publikums der erste Start einer Flüssigkeitsrakete in Europa glückte. Der Flugkörper, eine Konstruktion von 70 Zentimetern Höhe und 30 Zentimetern Durchmesser, hob mit dumpfem Zischen vom Erdboden ab, stieg etwa 100 Meter in die Höhe und stürzte nach einer horizontalen Drehung wieder zu Boden. Nach diesem erfolgreichen Versuch überschlugen sich die Sensationsmeldungen in der Presse, die verkündete, dass der Vorstoß in den Weltraum nur noch eine Frage der Zeit sei. Denn nach dem Zweck seiner Rakete befragt gab Hückel an, sie solle in erster Linie der „Erschließung des luftleeren und luftverdünnten Raumes in der Stratosphäre dienen“. Zur gleichen Zeit, in der Winkler und Hückel den ersten erfolgreichen Start ihrer Rakete vollführten, arbeitete ein kleiner Stab von Ingenieuren in den nicht weit entfernten Junkerswerken in Dessau an dem streng geheimen Projekt eines Stratosphären-Flugzeugs, mit dem man ebenfalls anstrebte, in größte Höhen vorzudringen. Gerüchte über dieses Flugzeug kursierten schon seit längerer Zeit, doch hatte die Presse bis dahin vergeblich versucht, darüber Informationen von Junkers zu erhalten. Als dieser nun im Frühjahr 1931 auf das gesteigerte öffentliche Interesse reagierte und erste Details über seine Neuentwicklung preisgab, prognostizierten nicht wenige das Ende der noch jungen Raketen-Träume, schien doch mit der von Junkers gebauten Maschine nicht nur der bemannte, sondern vor allem der kontrollierte und somit sichere Flug in bis dahin unbekannte Höhen nun unmittelbar bevorzustehen." [...]

Currently, it is uncertain how well a typical ground-based simulator's hexapod motion system can simulate the aggressive motion during airplane upset. To address this issue, this thesis attempts to improve simulator motion for upset recovery simulation by defining new motion fidelity criteria, implementing body frame filtering, and improving an existing adaptive motion drive algorithm. The successfully improved adaptive algorithm was used to conduct a paired comparison experiment to study the effects of trade-offs between translational and rotational motion cues on pilot subjective fidelity and upset recovery performance. Analysis of the experimental data found that pilots generally rejected motion with false lateral cues and they preferred the presence of rotational cues for moderate roll angles. Also, performance analysis suggested that roll cues helped improve lateral control. Overall, pilots preferred to have simulator motion during upset simulation and significant improvements in performance were observed when simulator motion was present.

La motivació de la tesis deriva en el interès de la indústria aeronàutica a explotar, per mitjà d'un disseny adaptat, la utilització del gir d'esquerda per protegir els reforços situats davant una esquerda que s'està propagant en la xapa d'una estructura integral. L'objectiu principal és l'avaluació i predicció del gir d'esquerda en situacions de càrrega pròximes a Mode I, proporcionant una eina de modelització i un criteri confident. L'entorn industrial sota el qual s'ha realitzat aquest treball requereix una predicció ràpida del comportament estructural proporcionant informació útil als constructors. Per aquest motiu la predicció del gir d'esquerda s'ha investigat utilitzant la teoria linear elàstica de la mecànica de la fractura (LEFM) i l'anàlisi amb elements finits (FEA).Durant aquest treball s'ha demostrat la importància i necessitat de caracteritzar el camp de tensions a la punta de l'esquerda amb el factor d'intensitat de tensió (SIF) conjuntament amb un segon paràmetre. La tensió uniforme, no singular, normal a la línea de l'esquerda i dependent en la geometria i càrrega de la proveta, es a dir la tensió T, ha estat seleccionada com a segon paràmetre per dur a terme les prediccions del gir d'esquerda.El criteri més desenvolupat per predir el gir d'esquerda en situacions pròximes a Mode I és el proposat per Buczek, Herakovich, Boone et al., anomenat WEFO en la tesis. Aquest combina el criteri de tensió principal màxima amb la tensió T i considera efectes d'anisotropia. LEFM s'ha utilitzat també en la predicció del gir d'esquerda sota càrregues quasi estàtiques controlant en tot moment la plastificació del lligament.En la investigació d'eines de modelització/simulació s'ha tingut en compte les capacitats d'aquestes en el camp de la mecànica de la fractura, de disseny, d'implementació, així com la complexitat d'ús. Tot i que hi ha un gran ventall de Softwares que compleixen els requeriments assenyalats, només aquells que es trobaven a l'abast de l'autor s'han analitzat. StressCheck ha estat escollit com a resultat de la investigació. L'avaluació de la propagació de l'esquerda en provetes compactes en tensió (CT) i en provetes amb dos elements reforçants (2SP) sota els règims de Paris i Forman ha estat satisfactòria.Un pas important ha estat la implementació de la capacitat d'extracció de la tensió T. La demostració de la fiabilitat en el seu càlcul s'ha demostrat mitjançant resultats en la literatura i càlculs analítics en provetes de doble biga en volada (DCB). Un aspecte a tenir en compte és la importància en realitzar anàlisis no linears geomètrics pel càlcul del SIF i la tensió T.Prediccions en la trajectòria de l'esquerda s'han realitzat en base amb els resultats obtinguts en l'estudi de modelització. La millor trajectòria s'ha predit per mitjà del criteri WEFO. No obstant, les diferents trajectòries obtingudes per una esquerda propagant-se en la direcció T-L o L-T no són comparables amb els resultats experimentals.Aquestes deficiències estan relacionades en la definició del punt d'inestabilitat de l'esquerda. Algunes referències posen de manifest que hi ha experiències on l'esquerda es comporta de forma estable tot i mostrar T > 0. Per un altre banda, els criteris WEF i WEFO defineixen la inestabilitat dependent d'una distancia específica del material, rc. Però la seva definició no és única i no existeix cap acord sobre el seu càlcul.L'autor proposa un criteri derivat dels criteris existents i basant-se en els assajos, simulacions i resultats obtinguts. Aquest deriva del treball de Pettit i la tensió T normalitzada, TR, proposada per Pook. La fiabilitat d'aquest criteri es demostra amb la proveta DCB. Les prediccions de la trajectòria de l'esquerda en la proveta cruciforme no són tant satisfactòries. Tot i així, s'ha d'accentuar que el criteri desenvolupat proporciona la predicció més acurada. / The motivation of this thesis started from the interest of aeronautical industry to exploit the utilization of crack turning to protect stiffeners in front of an approaching skin-crack in integral structures by a tailored design. The main objective was to assess and predict crack turning under nearly Mode I situations on structures that reproduce aeronautical conditions by providing a modelling tool and a reliable criterion. The industrial environmental in which this work has been carried out requires a fast prediction of the structural behaviour to provide useful inputs to aircraft designers. It is for this reason that the crack turning prediction was investigated by means of LEFM and FEA. During this work it has been shown the importance and necessity of a second parameter for the characterisation of the stress field at the crack tip besides the SIF. Among the different proposed second parameters, the uniform non-singular stress, normal to the crack line and dependent on the type of loading and specimen geometry, i.e. the T-stress, was selected for crack turning predictions due to both calculation simplicity and its independence of the crack tip distance. The most developed criterion for crack turning predictions near Mode I loading is the criterion proposed by Buczek, Herakovich and Boone et al., called the WEFO-criterion. This is the Maximal Principal Stress criterion implemented with the T-stress and taking into account anisotropic effects. A challenge of this thesis was to overcome the lack of prediction on crack turning provided by this last criterion.Although the validity of LEFM is restricted, it was applied for the prediction of crack turning for quasi-static loading while paying attention to possible plastification. A screening of existent commercial and non commercial tools was carried out in respect to their fracture mechanics capabilities, their design abilities, implementation as well as their complexity. Although, there are many software possibilities, only those within the reach of the author were evaluated. This resulted in the selection of the commercial tool StressCheck®. The assessment of crack propagation on compact tension and two stringer specimens governed by the Paris and Forman regimes was satisfactory compared with experimental results using the material data from simple standard specimens.An important step was the implementation of the T-stress extraction facility in the tool and the evidence of its reliability. The latter was proved by literature and analytical calculations on DCB specimens. An important finding was the importance to perform geometric non-linear analyses for computing SIF and T-stress to find values comparable with literature data and analytical calculations. Taking into account the results obtained on the modelling study, crack path predictions were performed. The best prediction by means of existing criteria was reached by the WEFO-criterion. Different crack paths were predicted for a crack propagating in T-L or L-T directions. However, these predictions were not satisfactorily reliable: the point in the crack path where crack turning should take place was not predicted adequately. Additionally, the crack paths were similar for T L and L-T directions. These deficiencies are related with the definition of the crack path instability. Some literature results have shown that in some experiences the crack behaved in a stable manner even if T > 0. Moreover, WEF and WEFO criteria define crack instability to be related with a material specific distance, rc, but, there is no agreement about its definition. Based on tests, simulation results and observations noted during this work, a compilation criterion was proposed. This is based on the work of Pettit and the normalised T-stress, TR, proposed by Pook. Its reliability was successfully proved on the DCB. The crack path predictions on the CFS were not as satisfactory. But even at its worst the developed criterion was the most accurate.

This thesis will analyze the Z-wing configuration. The Z-wing configuration is basically an airplane that has one of the wings placed at the forward section of the fuselage and the other wing placed on the other side far aft at the fuselage. This configuration creates a lot of different and unwanted forces and moments due to a differential in lift and drag between both the wings and the main objective with this thesis is to get a Z-wing to fly straight and level flight without these strange and unwanted forces and moments over it. Therefore the contribution of the wings different parameters to different moments and forces have been mapped out. Parameters such as the angle of incidence, wing span, dihedral, placement of wings etc. All the calculations done regarding the aerodynamic forces on the Z-wing have been performed in the Tornado, which is a program that runs in MATLAB and uses Vortex Lattice Method for its calculations. The outcome was that a steady level flight was possible. The configuration does have a lot of disadvantages. It will be very difficult to control in pitch, yaw and roll, although a backwards sweep of the front wing and a backwards sweep of the aft wing made roll control much better.