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"This work provides the reader with a comprehensive historical survey--including technical specifications, drawings, and photographs--of each type of fixed-wing aircraft used by U.S. military forces over an 86-year period to carry out the airlift mission"--Provided by publisher

Based on current plans, the never-ending saga of the planned European (joint? harmonised? coordinated?) procurement of a new military transport aircraft should finally produce some substantial results by the end of the year. However, you'd better not bet your money on it, because while there is indeed a general consensus on the need for such an aircraft, there also is a similarly general shortage of money, plus the usual panorama of lack of common views and diverging national interests. This situation is creating the preconditions for an "FTA showdown" over the next few months. (Military Technology/SWP)

This paper focuses on the experimental characterization of the vortex structures that develop in the aft fuselage region and in the wake of a simplified geometry of a military transport aircraft. It comes within the framework of the military applications of airflow influence on airdrop operations. This work relies on particle image velocimetry measurements combined with a vortex-tracking approach. Complex vortex dynamics is revealed, in terms of vortex positions, intensities, sizes, shapes and fluctuation levels, for both closed and opened cargo-door and ramp airdrop configurations.

The controllability of military transport aircraft deteriorates at heavy single piece landing. To solve this problem and a specific methodology for pilotage of the pre-emption, and automation tools are being developed. Preliminary study ofpilotage technique and authomatic control algorythm demand a reliable mathematical model of aircraft dynamics at cargo item drop. Such model should take into account significant change in the position of the aircraft center of mass and aircraft inertia tensor. Simplified models were based on modeling the movement of the center of mass and rotation around the center of mass of the aircraft. Such models do not take into account the inertial forces and moments of moving a cargo item. This circumstance does not allow to obtain reliable results in the simulation. The article presents the description of the complete mathematical model of the movement of military transport aircraft in landing of a cargo item. Examines the complex material system of solids and a detailed description of the properties of its components. The equations of motion of the aircraft as a system carrier (aircraft without a cargo item) and wear (of moving a cargo item) bodies to reflect the changes in the inertia tensor. The functioning of the power plant, steering actuators, flight control system, an exhaust chute, the sensors of the primary information are taken into account. The equations of motion for systems of bodies projected on the aircraft reference plane are being recorded. This approach takes into account changes of the inertia tensor and the position of the main central axes of inertia in the process of landing of a cargo item. It allows us to simulate the condition of the aircraft at all speeds of the pitch, normal overload, and masses of single piece and placement, as evidenced by the high convergence of modeling results with data from flight tests. ; При десантировании тяжелых моногрузов ухудшается управляемость военно-транспортного самолета. Для решения этой проблемы применяется специальная методика пилотирования с упреждением, разрабатываются средства автоматизации. Для предварительной проработки методики пилотирования и для синтеза алгоритма автоматического управления необходимо иметь достоверную математическую модель динамики самолета при десантировании моногруза. Такая модель должна учитывать значительное изменение положения центра масс и тензора инерции самолета. В этой связи при использовании упрощенных моделей движения центра масс и вращения вокруг центра масс самолета не учитываются инерционные силы и моменты от перемещающегося моногруза, действующие на него, что не позволяет получать достоверные результаты при моделировании. В статье представлено описание математической модели движения военно-транспортного самолета при десантировании моногруза как сложной материальной системы твердых тел с подробным описанием свойств ее компонентов. Представлены уравнения движения самолета как системы несущего (самолет без моногруза) и носимого (перемещающегося моногруза) тел с учетом изменения тензора инерции. Учитывается функционирование силовой установки, рулевых приводов, системы управления самолета, вытяжного парашюта, датчиков первичной информации. Применяется форма записи уравнений движения системы тел в проекциях на оси связанной с самолетом системы координат. Такой подход учитывает изменения тензора инерции и положения главных центральных осей инерции в процессе десантирования моногруза. Это позволяет достоверно моделировать состояние самолета при любых значениях скорости тангажа, нормальной перегрузки, а также массах моногрузов и вариантах их размещения, что подтверждается высокой сходимостью результатов моделирования с данными летных испытаний.

Purpose The growth in air mobility, rising fuel prices and ambitious targets in emission reduction are some of the driving factors behind research towards more efficient aircraft. The purpose of this paper is to assess the application of a blended wing body (BWB) aircraft configuration with turbo-electric distributed propulsion in the military sector and to highlight the potential benefits that could be achieved for long-range and heavy payload applications. Design/methodology/approach Mission performance has been simulated using a point-mass approach and an engine performance code (TURBOMATCH) for the propulsion system. Payload-range charts were created to compare the performance of a BWB aircraft with various different fuels against the existing Boeing 777-200LR as a baseline. Findings When using kerosene, an increase in payload of 42 per cent was achieved but the use of liquefied natural gas enabled a 50 per cent payload increase over a design range of 7,500 NM. When liquid hydrogen (LH2) is used, the range may be limited to about 3,000 NM by the volume available for this low-density fuel, but the payload at this range could be increased by 137 per cent to 127,000 kg. Originality/value The results presented to estimate the extent to which the efficiency of military operations could be improved by making fewer trips to transport high-density and irregular cargo items and indicate how well the proposed alternatives would compare with present military aircraft. There are no existing NATO aircraft with such extended payload and range capacities. This paper, therefore, explores the potential of BWB aircraft with turbo-electric distributed propulsion as effective military transports.