Global warming caused by combustion of fossil fuels is a hot topic in today’s society and the world is constantly trying to makes steps towards a brighter tomorrow with stricter environmental laws and research of alternative fuels. A great propulsion system is however not great solely of it being environmental friendly, it must also achieve other requirements. A comparison using different propulsion systems and different fuel types has been made and evaluated in four different categories; power; range; cost and environmental impact. The process of scientifically compare systems using given attributes is a big part of the study and is hoped to yield inspiration to the reader to apply to their own application, not necessarily using the same categories. The result has been assembled in a matrix and depending on what category one prefers the most, different results are presented. A clear observation is a lack of range for all of the systems using electricity due to the low energy density compared to fossil fuels. Hydrogen fuel cells and ICE are however constrained by the volume required to store hydrogen but applications can surely be found where the great gravimetric energy-density can be utilized at its full potential. The future of alternative fuels and propulsion systems are looking great checking the improvements of technology on electrical components such as batteries, fuel cells and solar cells the last 10 years. The improvements not only affecting performance such as increased energy-density and power but also cost, making them more desired by the common man.

The perfect wing is a dream that many airplane manufactures have been striving to achieve since the beginning of the airplane. The goals are usually the same for everyone; - Increase lift - Reduce drag - Minimize weight A combination of these goals lead to a decrease in fuel consumption, which in turn reduces pollution in our atmosphere with the added bonus of an increase in economic revenue. One way to improve performance is to modify the tip of the wing structure, which has become a common sight on today’s airplanes. With the help of computational programs, the effects on drag due to wingtip devices can be previewed.

Rapporten innefattar en teoretisk analys av ett vindkraftsverks propeller. Syftet har varit att underlätta tillverkandet av en propeller, med hänsyn till bladens vridning och en varierande vindhastighet. Det tänkta vindkraftverkets ingående parametrar finns att studera i Bilaga 1 – Ingående parametrar. Utifrån dessa parametrar kunde en maximal effektkoefficient på 0.51 uppnås, vilket skulle motsvara en effekt på 417 kW som i sin tur motsvarar en försörjning av ungefär 40 hushåll. Analysen omfattar även pitchreglering, som syftar till att behålla hög effektivitet hos vindkraftverket, även om vindhastigheten varierar.

This paper is explaining the important design phases of dimensioning an unmanned conventional aircraft from scratch and will also design one according to a few chosen requirements. The design phases discussed will be all from wing dimensioning to stability and spin recovery, aircraft performance requirements and how to select a motor which overcomes these. As well as the optimal rate of climb for improved efficiency is discussed. In the end an aircraft which manages the set requirements and is stable in pitch managing spin recovery with no problem will have been dimensioned.

It is sometimes easily assumed that an experimental measurement will closely mimic the results from an associated theoretical model. The purpose of this project is to determine how close to a theoretical model - involving the component buildup method and the quadratic drag polar assumption - a Piper Archer II will perform in an actual test flight. During the test flight, the Archer II showed a similar correlation between air speed and performance as the model. The actual performance numbers were, however, consistently lower than their theoretical counterpart.

Programmet som skapats ger generella approximationer över hur en flygplanspropeller skall dimensioneras. Det kan uppstå skillnader mellan det praktiska och teoretiska värdena hos propellern. Den vingprofil som dimensionerats är FX67-K-170. Ett optimalt tillstånd har beräknats för denna propeller. Propellerverkningsgraden kan vara så högt som 91 % med en relativ hastighet mellan vind och farkost på 86 m/s och med ett varvtal på 1200 rpm. Avanceringstalet beräknas då till 1,44. Torderingen är som störst vid början av den verkande delen av propellern med en pitchvinkel på 92 grader och ut på spetsen, 31 grader.

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Dubai International Airport has set as an aim to become the leading connecting hub between Europa and Asia. As to be cope with the stresses being put on the airspace in terms of holding times, fuel efficiency and environmental impacts, an analysis has been made concerning the future technology in air traffic management: Time based Operations. This project has revealed that it is possible to maintain the current mean capacity of 29 aircraft/ hour while flying an optimal vertical descent profile. However, exceeding that capacity is not possible with the methods used in this project. The conclusion is that the only forward is Dynamic Controlled of Arrival, together with the reorganization of the entire airspace of Dubai.

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The objective of this internship was to study the physical properties of a thermal protection used for a space probe to be launched for a mission to Mars. The protection is composed of two main components. The topmost part is a cork derivative that deteriorates via ablation and pyrolysis in order to reduce the amount of heat transferred to the vehicle's main body. The junction between the ablative layer and the spaceship is ensured by a sandwich material composed of two carbon skins separated by a grid of Aluminium honeycomb cells. In a first part, numerical models of variable complexity were created to simulate the properties of the sandwich material (thermal conductivity, specific thermal capacity). The models' results were then compared to experimental measurements to upgrade Astrium's databases concerning similar products with new values for the physical properties of the studied materials. The results obtained by both the model and the experiments were found to be in accordance, which justies the validity of the simulation, and the choices made for the values of physical properties. In addition, a thorough consideration of the in　uence of phenomena neglected was performed to justify the stability of the numerical computations. In a second time, a staggered coupled simulation was developed to study the physical behaviour of the ablative protection. A thermal simulation considered the ablation, pyrolysis and thermal conduction. A mechanical simulation considered the swelling induced by the heating of the cork material. The results (temperature, swelling, density) from infra-red experiments and plasma jet testing were compared to the prediction of the coupled simulation. Although a substantial discrepancy remained between experimental and numerical results, the mere fact that a working program emulating at the same time ablation and swelling gave results physically coherent was already a positive advance in this domain.