An ultralight aircraft based airborne geophysical system was developed and operated by the Council for Geoscience during the period 1997-2004. The aim of this project was to collect geophysical data at lower cost and higher resolution than was possible using conventional airborne systems. This dissertation describes the development of the radiometric systems used in the ultralight airborne survey project. During the course of the study, a number of obstacles to the successful collection and processing of radiometric data with the ultralight-mounted systems were encountered. These are described and solutions proposed. To facilitate the development hardware systems and processing methods, a Monte Carlo simulation method was developed to produce spectra containing realistic signal and noise components. This method was applied to the selection of detector materials and the specification of detector sizes as well as being used to simulate large spectral data sets for the development and testing of processing and calibration procedures. Radiometric data follow a Poisson Distribution, with the signal to noise ratio being dependent on the count rate recorded, which, in turn, depends on the size of the detector used. The ultralight aircraft were capable of carrying a detector one eighth the size of that used in conventional systems. To allow for the use of the smaller detector, the noise adjusted singular value decomposition (NASVD) processing technique was employed. While this technique is commonly applied in noise-reduction, the original application, namely the determination and mapping of spectral components was also utilised. iii During the course of the study no suitable calibration facilities were available inside South Africa. This necessitated the development of a spectral stripping method, utilising a technique generally applied to much higher resolution spectral data collected under laboratory conditions. Simulation studies and practical application showed that this method performs well, in some cases outperforming the conventional stripping method. The method is also applicable to the study of anthropogenic radionuclides, where suitable calibration facilities are generally unavailable. An alternative to the conventional method of altitude correction was also applied to the radiometric data collected with the ultralight-mounted systems. Using simulated data, a spectrometer based on a bismuth germanate (BGO) detector was designed and constructed. This material is significantly denser than the more usual thallium activated sodium iodide used for detector fabrication and has a higher effective atomic number, giving it a greater photopeak efficiency. However the poor light production of this scintillation material results in a poorer energy resolution than a conventional detector. Initial tests using small BGO detectors were promising and a larger detector was acquired and tested. Unfortunately the poor energy resolution and high cost of BGO detectors led to the conclusion that they did not offer the advantages initially hoped for. Nevertheless a number of successful surveys were flown using the BGO detector. Ultralight-mounted systems were found to be ideal for small surveys where high spatial resolution is required. The ultralight systems were successfully applied to the detection of radioactive pollution on a number of sites in the Witwatersrand and related gold fields and one site where anthropogenic radionuclide contamination was present. In some cases, the data could be compared to data collected using a conventional airborne radiometric system. Here the ultralight- mounted systems were found to perform satisfactorily, albeit with a poorer signal to noise ratio except where adverse flying conditions necessitated flying at high altitude. The strengths, weaknesses and potential applications of ultralight-mounted airborne radiometric systems are discussed.

Thesis (LL.M.). / Written for the Faculty of Law. Title from title page of PDF (viewed 2009/06/17). Includes bibliographical references.

Thesis (M.S.)--Ohio University, November, 2006. / Title from PDF t.p. Includes bibliographical references.

This work describes digitalization and creation of ultralight aircraft 3D model in order to create accurate moulds for fuselage lamination. Right choice of technology is based on background research. Designed procedures are described in detail as well as used equipment, hardware and software. Objective of this project is application of available methods of digitalization to create 3D aircraft model and its usage for accurate mould design.

The aim of this diploma thesis is to design a new high-wing aircraft for the company TL ultralight using the structural elements from another models from their portfolio. The design is created with an emphasis on crew comfort and cabin ergonomics. The first part of the thesis focuses on the description of the basic requirements for the aircraft and its classification in aviation regulations. It also contains a research part of competing types and currently produced type, which the proposed aircraft should replace in the company's portfolio. Then follows the characteristics of the individual parts of the airframe, the specification of the parts, which will be used from another types from portfolio, and parts which will be completely designed. Great emphasis is placed on the layout of the interior and its design and ergonomic. The proposed aircraft then demonstrates theoretical calculations of basic performances and a preliminary mass analysis. In the end, the benefits of the newly designed aircraft are evaluated with respect to the competing types.

This thesis deals with the control system of two-seater aircraft corresponding to CS-23 Level 2. First load calculations of each control surface are performed using the proses described in previous CS-23 regulation. This load is calculated trought the steering mechanism to control elements in cockpit. The resulting forces on the control elements are compared with the requi-rements in CS-23. Because the steering forces meets requirements is not necessary to propose changes in steering kinematics. However, there are further suggested ways of adjusting the control in case the external load would increase during further development of the airplane. At the end, the strength calculation of entire mechanism is preformed.

This diploma thesis deals with digital data processing during the design of a mould of ultralight airplane airframe. The final digital model meets the demands on manufacturability by using CNC machining. The realization, in compliance with the reverse engineering approach, was conceived in four phases, which had to be solved step by step in order to preserve the continuity of the process. The phases correspond to the main chapters of the practical part of the thesis. The first part is focused on 3D digitalization of airplane fuselage by using an optic scanner ATOS and photogrammetric system Tritop. The result of this part is digital data of fuselage geometry in form of polygon grid. Next part deals with software reconstruction of collected data – by optimizing polygon grid in order to provide suitable base for surface modeling. The third part, the most time demanding, handles the creation of airplane fuselage surface model. Geometry has to satisfy requirements for smoothness and tangential or curvative connection of surfaces, including other requirements resulting from model usage. The final part of the thesis documents the procedure of deriving a mould from the aircraft fuselage geometry.

This thesis addresses the design of ultralight aircraft as a one regulation UL-2 and basic aerodynamics characteristics of the individual parts of the airplane. Furthermore, we discuss the production process and the production itself tail and static strenght tests.

This diploma thesis describes the design of retractable landing gear for the NG-4 ultralight aircraft. Its main part consists of general principle of gear retraction, kinematics analysis, load calculation and structural analysis, material selection and means of controlling by pilot. The thesis contents marginally the typology of aircraft landing gears and their evolution.

The diploma thesis involves the design of certification static strength tests for the newly developed aircraft of the TL-Ultralight company. At the beginning of the work, the theory of aircraft testing is generally discussed with emphasis on static strength tests. Furthermore, an analysis of the requirements of the Czech regulation UL 2 and the German LTF-UL, which represent the certification basis for this aircraft, is performed. The requirements of regulations on the construction of the aircraft (or its individual parts) and the requirements for strength tests are discussed in detail. Based on the regulation and the provided calculation protocols, individual test cases and test plans of the wing, tail surfaces, engine bed, and chassis are calculated and prepared. In the end, the calculation of the rocker system and the basic design of jigs are performed.