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The purpose of this study is to analyze influence of airfoil profile on lateral-directional flying quality of flying wing aircraft. The lateral-directional stability is always insufficient for aircraft with the layout due to the absence of vertical stabilizer. A flying wing aircraft with double-swept wing is used as research object in the paper.

The 3D model is established for the aircraft with flying wing layout, and parametric modeling is carried out for airfoil mean camber line of the aircraft to analyze lateral-directional stability of the aircraft with different camber line parameters. To increase computational efficiency, vortex lattice method is adopted to calculate aerodynamic coefficients and aerodynamic derivatives of the aircraft.

It is found from the research results that roll mode and spiral mode have a little effect on lateral-directional stability of the aircraft but Dutch roll mode is the critical factor affecting flying quality level of such aircraft. Even though changes of airfoil mean line parameters can greatly change assessment parameters of aircraft lateral-directional flying quality, that is kind of change cannot have a fundamental impact on level of flying quality of the aircraft. In case flat shape parameters are determined, the airfoil profile has a limited impact on Dutch roll mode.

Influences of airfoil profile on lateral-directional flying quality of aircraft with double-swept flying wing layout are revealed in the thesis and some important rules and characteristics are also summarized to lay a theoretical basis for design of airfoil and flight control system of aircraft with the layout.

DURING the past 40‐odd years or so, a number of experimental aeroplane types have been invented, visualized, designed, constructed and even flown which, in a quite unorthodox manner, had neither behind the wing nor in front of it any sort of stabilizing and/or controlling surfaces.

In the First Russian Soaring Flight Competition at Feodosia (Crimea) in 1923, a very light “all‐wing” sailplane took part. The parabola plan shape of its wing, its small span and low aspect ratio raised general interest. The designer and pilot of this Flying Wing was the Russian student of aeronautical engineering, B. J. Tscheranowsky.

Even in these days of long development periods of conventional metal structures and of huge production orders for orthodox aeroplanes the interest in the Flying Wing type and in tailless designs is by no means asleep.

IN considering the size of wings, which aero‐plane designers require to lift a given weight, the fact is very apparent that lifting surfaces have become smaller as the art of aeroplane design has advanced. Fig. 1 shows the trend of this development from pre‐war days up to now, expressed by a steady increase in wing loading (lb. per sq. ft.). How is this development likely to go on, and where will it end ?

The purpose of this paper is to provide a review of recent developments in miniaturised flying robots.

Following a brief consideration of micro‐ and nano‐aerial vehicles, the paper discusses recent US and European research into the development of miniaturised flying robots.

This paper shows that research into miniaturised flying robots is gaining pace and much is being funded by the US military. Two major strands of research are devices which mimic the flight dynamics of insects and living insect‐microtechnology hybrids (cyborgs). The technologies remain at an early stage of development but covert surveillance and intelligence gathering are key future applications.

The paper provides a technical review of the latest developments in miniaturised flying robots.

As measuring flight performance by experimental methods requires a lot of effort and cost, theoretical models can bring new perspectives to aircraft design. This paper aims to propose a model on the direct calculation of wetted area and L/D_max.

Model is based on idea that the wetted area is proportional to aircraft gross weight to the power of 2/3 (W_g^2/3). Aerodynamic underpinning of this method is based on the square–cube law and the claim that parasitic drag is related to the S_wet/S_wing. The equation proposed by Raymer was used to find the L/D_max estimate based on the calculated wetted area. The accuracy of the theoretical approach was measured by comparing the L/D_max values found in the reference literature and the L/D_max values predicted by the theoretical approach.

Proposed theoretical L/D_max estimate matches with the actual L/D_max data in different types of aircraft. Among the conventional tube-wing design, only the sailplanes have a very low S_wet/S_wing. The S_wet/S_wing of flying wings, blended wing bodies (BWBs) and large delta wings are lower than conventional tube-wing design. Lower relative wetted area (S_wet/S_wing) is the key design criterion in high L/D_max targeted designs.

The proposed model could be used in wing sizing according to the targeted L/D_max value in aircraft design. The approach can be used to estimate the effect of varying gross weight on L/D_max. In addition, the model contributes to the L/D_max estimation of unusual designs, such as variable-sweep wing, large delta wings, flying wings and BWBs. This study is valuable in that it reveals that L/D_max value can be predicted only with aspect ratio, gross weight (W_g) and wing area (S_wing) data.

A review is attempted with the objective to indicate the most promising aeronautical technology for application to future subsonic civil transport aircraft.

A methodology is put forward, according to which direct operating costs (DOC) are examined in order to identify those that can be reduced, and, then, specific technology is assessed in relation to its efficiency in reducing these DOC, operational feasibility and cost‐effectiveness.

This assessment suggests the selection of propfan and powered lift as the leading future aeronautical technology. These findings are supported by a comparison of a number of advanced technology designs.

Provides a starting point for further investigation of advanced aeronautical technology and unconventional configurations for large subsonic civil transport aircraft.

A collaborative design environment is needed for multidisciplinary design optimization (MDO) process, based on all the modules those for different design/analysis disciplines, and a systematic coupling should be made to carry out aerodynamic shape optimization (ASO), which is an important part of MDO.

Computerized environment for aircraft synthesis and integrated optimization methods (CEASIOM)-ASO is developed based on loosely coupling all the existing modules of CEASIOM by MATLAB scripts. The optimization problem is broken down into small sub-problems, which is called “sequential design approach”, allowing the engineer in the loop.

CEASIOM-ASO shows excellent design abilities on the test case of designing a blended wing body flying in transonic speed, with around 45 per cent drag reduction and all the constraints fulfilled.

Authors built a complete and systematic technique for aerodynamic wing shape optimization based on the existing computational design framework CEASIOM, from geometry parametrization, meshing to optimization.

CEASIOM-ASO provides an optimization technique with loosely coupled modules in CEASIOM design framework, allowing engineer in the loop to follow the “sequential approach” of the design, which is less “myopic” than sticking to gradient-based optimization for the whole process. Meanwhile, it is easily to be parallelized.

The purpose of this paper is to experimentally analyze the effect of wing shape of various insects of different species in a flapping micro aerial vehicle (MAV).

Six different wings are fabricated for the MAV configuration, which is restricted to the size of 15 cm length and width; all wings have different surface area and constant span length of 6 cm. The force is being measured with the help of a force-sensing resistor (FSR), and the coefficients of lift were calculated and compared.

This study shows that the wing “Tipula sp” has better value of lift than other insect wings, except for the negative angle of attacks. The wing “Aeshna multicolor” gives the better values of lift in negative angles of attack.

This paper lays the foundation for the development of flapping MAVs with the insect wings. This type of wing can be used for spying purpose in the military zone and also can be used to survey remote and dangerous places where humans cannot enter.

This paper covers all basic insect wing configurations of different species with exact mimics of the veins. As the experimental investigation was carried for different angle of attacks, velocities and flapping frequencies, this paper can be used as reference for future flapping wing MAV developers.