Current Issue : January - March Volume : 2016 Issue Number : 1 Articles : 5 Articles
An efficient empirical approach was developed to accurately represent the blast shock wave loading resulting from the launch of a\nmissile from a military aircraft to be used in numerical analyses. Based on experimental test series of missile launches in laboratory\nenvironment and from a helicopter, equations were derived to predict the time- and position-dependent overpressure.The method\nwas finally applied and validated in a structural analysis of a helicopter tail boom under missile launch shock wave loading....
The purpose of this paper is devoted to developing a chaotic artificial bee colony algorithm (CABC) for the system identification\nof a small-scale unmanned helicopter state-space model in hover condition. In order to avoid the premature of traditional artificial\nbee colony algorithm (ABC), which is stuck in local optimum and can not reach the global optimum, a novel chaotic operator with\nthe characteristics of ergodicity and irregularity was introduced to enhance its performance.With input-output data collected from\nactual flight experiments, the identification results showed the superiority of CABC over the ABC and the genetic algorithm (GA).\nSimulations are presented to demonstrate the effectiveness of our proposed algorithm and the accuracy of the identified helicopter\nmodel....
The airline industry has been marked by numerous incidents. One of the first, who accompanied the start of\noperation of the first airliners with jet engines, was directly related to the portholes. Indeed, the banal form of the\nwindows was the source of stress concentrations, which combined with the appearance of micro cracks, caused the\nexplosion in flight of the unit. Since that time, all aircraft openings receive special attention in order to control and\nreduce their impact on the aircraft structure. In this paper we focus on the representation and quantification of stress\nconcentrations at the windows of a regional jet flying at 40000 feet. To do this, we use a numerical method, similar\nto what is done at major aircraft manufacturers. The Patran/Nastran software will be used the finite element software\nto complete our goals....
This study has been given prominence and confirmed by extensive documentation while recent visualizations\nobserved in a wind tunnel have revealed that rectilinear vortex flows from different angles interacting with one another\nabove warheads. My experimental research has indicated the many and very specific series, by visualizations of\nwisps of smoke trails, of vortex structures of a preferential nature above a warhead where Ã?²=68.6Ã?°. The positioning\nof those structures has thus been determined with regard to the application of very general criteria governing the\nstability of vortex flows. What have also been exposed are the specific aspects of vortex flows together with some\ncomments concerning the bursting of vortices above the warhead. The purpose of this study is to optimize the\nconnection between marine, air and land forms such as sails, the wings of aircraft, cars and trains ââ?¬â?? and the stability\nof fluid flows around such forms....
In 2002 Australia became the first nation to promulgate certification standards for the commercial use of drones\nor Unmanned Aircraft Systems (UAS). Since that time the Australian Civil Aviation Safety Authority (CASA) has\nplayed a key role both domestically and internationally through the International Civil Aviation Organization (ICAO) in\nassisting to develop technical guidance materials that will enable contracting states to develop UAS regulations. An\narduous component of this task is the fact that all existing aircraft are capable of being unmanned. Moreover, given\nthe unbounded nature of aircraft operations, UAS regulations necessarily require international harmonisation. But\nthe objective of developing universal UAS standards is still far from being finalised while the accelerating pace of\nUAS technological development continues to challenge traditional regulatory regimes and legal systems throughout\nthe world. This paper considers the broader legal issues associated with civilian UAS operations and their integration\ninto unsegregated civilian airspace. In particular the Australian UAS regulatory experience is examined with some\nunique constitutional limitations identified in relation to the application of the so-called ââ?¬Ë?commingling theoryââ?¬â?¢. It is\ncontended that such limitations may render void existing UAS regulation in certain situations ââ?¬â?? many of which are\nlikely to have adverse privacy implications. This paper strongly asserts that if the commercial benefits attendant to\nUAS operations is to be fully realised then their risks to society must be controlled through domestic legislation that\nis harmonised with internationally agreed standards....
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