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Re-fuelling and re-supply of LTAV and Airships while under-way is an important tool to extend the endurance and range of LTAV. The United States Navy (USN) developed and practiced various procedures to enable re-fuelling and re-supply at sea, starting with the Airship Tender USS Patoka in the 1920's, and developing those procedures until the end of the USN use of Airships in the early 1960's.
Results of the first phase of a rigid airship "D-20" creation for cargo transportation with lifting capacity up to 20 tons are considered. An airship feature is the opportunity of cargo transportation both on an outside load and inside of a vehicle hull.
The stratospheric platform airship as the communication infrastructure shall have an enough station keeping capability at a high altitude during a long term. This airship requires a very lightweight electric power system which can be operated continuously for a long term. In this case the combined system of the photovoltaics and the regenerative fuel cell is the most promising system as an onboard power plant. The development of a lightweight and highly reliable regenerative fuel cell is the most critical item for this advanced power plant.
High Altitude Platforms (HAPs) are airships or planes that will be located in the stratosphere at heights of approximately 17 - 22 km. They are gaining considerable attention at the moment as a delivery vehicle forbroadband communications and other services. The European HeliNet programme is one such project, now in its third year of study. We present a summary of results and a suggested architecture for the delivery of a cellular broadband network, the design of which is constrained by the mass and power available for the proposed Heliplat payload.
This paper presents the current status of the development of an autonomous blimp. Details are given on the hardware setup, which is currently almost operational. A flight decomposition allowing to define canonical navigation phases from takeoff to landing is proposed. For each phase a reduced model is determined and a controller is designed on the base of back-stepping techniques. This approach allows to consider the kinematic and dynamic requirement separately.
A thoroughly verified statistical model of learning with degenerative feedback is used to evaluate results of airship flight testing – the probability of mission success and its confidence limit. The main communication zest is as follows: testing with corrective action is considered as the process of a continuous vehicle’s perfection until all specification requirements are met and confirmed. The result can be used as a part of evidence for airship airworthiness certification.
In 1997, the airship research group FOGL was established at the University of Stuttgart, Germany. Among others, the remotely controlled airship Lotte was chosen as reference configuration to perform scientific investigations in the fields of aerodynamics, flight mechanics and control, aeroelasticity, structural design and solar propulsion systems. The present paper addresses theoretical and experimental aerodynamic studies on the Lotte configuration. An overview on the wind- and water-tunnel tests performed so far and a summarized description of the theoretical models developed is given.
The purpose of this paper is to analyze the dynamic stability and the controllability of the unmanned airship under development ; the KARI unmanned airship's over-all length of hull is 50m and the maximum diameter is 12.5m. For the analysis, the dynamic model of an airship was defined and aerodynamic derivatives were extracted from the wind tunnel test. The analysis results shows the efficiency of the control inputs such as control surfaces, thrust, tilting angle and differential thrust of motor at the low and high speed regime and the
Solar -hydrogen systems were analyzed regarding their usability as energy supply system for high altitude platforms. The main attention was directed to characteristics of current or near term available technology. Specific power weight of photovoltaics, electrolyser, fuel cell and gas tanks and their dependence on operation mode and power range were assessed. A pre-design of a solar-hydrogen energy system was carried out for an airship (volume 580,000 m³) withstanding wind speeds up to »130 km/h.