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Nomenclature xviii comprise 5 1 % of the entire vehicle weight. As MAVs get smaller, current state of the art batteries are too heavy, so they must remain tethered to the ground. One of the options which has been presented is a miniature turbinegenerator system to replace conventional batteries. A miniature turbine is a fluid powered machine that produces either electrical or mechanical power. A miniature turbine, as opposed to a micro turbine, is one manufactured using conventional fabrication techniques. For miniature turbines to be successful on MAVs the turbine and fuel must weigh less then 50 grams, produce 5 Watts of power, and take up less than 50 cm. The purpose of this work was to investigate whether a miniature turbine could serve as a power source on MAVs instead of batteries. This thesis describes the design, fabrication, and testing of a miniature turbine as well as the design of a fuel tank as a power source. 1.1 Turbine Overview The turbine described in this work was powered by compressed air during testing. However, the goal of the project is to use compressed nitrogen to drive the turbine. Nitrogen was chosen because it is inert and safe to release directly into the environment. Most of the research groups working on microturbines are using some type of combustible fuel such as liquid hydrogen. The big advantage to using a combustible fuel is the higher energy density. Liquid hydrogen has an energy density of about 4500 KJ kg"1 [Peirs, 2003] while compressed nitrogen has an energy density of about 50 KJ kg*1. However, there are a number of advantages to using a compressed gas. Combustible fuels greatly increase the size of the turbine because they require a compressor and a combustor sections, which a compressed gas turbine does not need. Another advantage of the compressed gas turbine is it exhausts cold gas, at or below room temperature, as opposed to hot gas, which is exhausted at a minimum of 300C [Epstein, 1997]. This is an important consideration when the turbine is in close proximity to electronic equipment or any materials that are sensitive to high temperatures as on MAVs. In addition, a MAV exhausting hot gas will easily be seen by infrared scans, while one driven by compressed gas will not. Liquid nitrogen will be inserted into silicon carbide fuel tanks, which are then capped and allowed to warm up to room temperature. This could potentially give a pressure of 46,000 psi in the tanks, but for safety and use with a thinner walled tube, 10,000 psi is the current goal. Once the tank is opened, a jet of nitrogen is directed at the impeller. Figure 1. 1 shows an overview of turbine down to a Micro Electrical Mechanical System (MEMS). MEMS devices are built using semiconductor fabrication techniques that severely limit the design. Axial, radial, and impulse turbines were investigated and because of its simplicity and ease to scale down to MEMS size, the impulse type was chosen. The reason simplicity was a factor in the choice of the turbine type is because the turbine will be competing with...