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The purpose of this paper is to mount Gurney flaps at the trailing edges of the canards and investigate their influence on aerodynamic characteristics of a simplified canard-configuration aircraft model.

A force measurement experiment was conducted in a low-speed wind tunnel. Hence, the height and shape effects of the Gurney flaps on the canards were investigated.

Gurney flaps can increase the lift and pitching-up moment for the aircraft model tested, thereby increasing the lift when trimming the aircraft. The dominant parameter to influence aerodynamic characteristics is the height of Gurney flaps. When the flap heights are the same, the aerodynamic efficiency of the triangular Gurney flaps is higher than that of the rectangular ones. Moreover, the canard deflection efficiency will be reduced with Gurney flaps equipped, but the total aerodynamic increment is considerable.

This paper helps to solve the key technical problem of increasing take-off and landing lift coefficients, thus improving the aerodynamic performance of the canard-configuration aircraft.

This paper recommends to adopt triangular Gurney flaps with the height of 3 per cent chord length of the canard root (c) for engineering application.

The purpose of this paper is to describe the new method for optimizing the topology of the control system frame for a canard missile to create its efficient model. Determining the minimum volume of the part risked losing some of the mechanical interfaces and functionality required of the frame. The proposed method must cope with these requirements and include a validation loop of the improved solution proposed by the software. The processing of the mathematical model to a printable form must take into account manufacturing technologies limitations and appropriate curvature continuities to avoid stress concentrations.

Real examples from the aerospace industry are presented and the process of determining a prototype is described. The optimization assumed leaving the largest volume of the domain. Strength analyses were performed on both the assembly fasteners and the robust prototype. Once all boundary conditions were validated, topological optimization was performed in the ANSYS environment. The algorithm of the optimization was presented.

Obtained fatigues showed the vast potential of topology optimization, efficient method of weight reduction in specific situations. It can be considered as an innovative approach to the manufacturing of products with a structure focused on the best possible correlation of weight and strength, for example of a canard rocket.

The paper introduces precise manufacturing technology of the inner frame for the missile’s control system, which ensures sufficient properties of the material, known as EBM.

THE impending maiden flight of the de Havilland DH.12I Trident at Hatfield heralds the arrival of the second generation of turbojet‐powered airliners and the Company which designed and built the world's first jet airliner—the Comet 1— s now first in the field with a 600 m.p.h. short‐to‐medium‐range civil transport of sophisticated design. With its rear‐fuselage‐mounted engines, the Trident disposes a configuration which was adopted and proved operationally by Sud Aviation in the Caravelle airliner, and which has been a design feature of the last eight British jet transport projects. However, lest it be thought that such a configuration was the exclusive brainchild of the French company, it is relevant to recall that as long ago as 1943, de Havilland project engineers were proposing the use of rear‐mounted jet engines. In that detailed and profoundly interesting book by Mr C. Martin Sharp, somewhat modestly entitled DH—An Outline ofde Havilland History, there is a brief mention, with three‐view drawings, of an early design study for the Comet airliner. This was a short‐range aircraft of canard configuration with three Ghost engines buried in the rear fuselage.

This paper aims to analyze the influence of the changings in geometrical parameters on the aerodynamic performance of the control canard projectiles.

Because of the mentioned point, the range of projectiles increment has a considerable importance, and the design algorithm of a control canard projectile was first written. Then, were studied the effects of canard geometric parameters such as aspect ratio, taper ratio and deflectable nose on lift to drag coefficient ratio, static margin based on the slender body theory and cross section flow.

The code results show that aspect ratio increment, results in an increase in lift-to-drag ratio of the missile, but increase in canard taper ratio results in increasing of lift-to-drag ratio at 1° angle of attack, while during increasing the canard taper ratio up to 0.67 at 4° angle of attack, lift to drag first reaches to maximum and then decreases. Also, static margin decreases with canard taper ratio and aspect ratio increment. The developed results for this type of missile were compared with same experimental and computational fluid dynamic (CFD) results and appreciated agreement with other results at angles of attack between 0° and 6°.

To design a control canard missile, the effect of each geometric parameter of canard needs to be estimated. For this purpose, the suitable algorithm is used. In this paper, the effects of canard geometric parameters, such as aspect ratio, taper ratio and deflectable nose on lift-to-drag coefficient ratio and static margin, were studied with help of the slender body theory and cross-section flow.

The contribution of this paper is to predict the aerodynamic characteristics for the control canard missile. In this study, the effect of the design parameter on aerodynamic characteristics can be estimated, and the effect of geometrical characteristics has been analyzed with a suitable algorithm. Also, the best lift-to-drag coefficient for the NASA Tandem Control Missile at Mach 1.75 was selected at various angles of attack. The developed results for this type of missile were compared with same experimental and CFD results.

This paper presents first sight on the longitudinal control strategy for an aircraft in the tandem wing configuration. It is an aerodynamic strongly coupled configuration that needs a lot of detailed aerodynamic analysis which describes the mutual impact of the main parts of the aircraft. The purpose of this paper is to build the numerical model that allows to make an analysis of necessary flaps (front and rear) deflection and prepare the control strategy for this kind of aircraft.

Aircrafts’ aerodynamic characteristics were obtained using the MGAERO software which is a commercial computing fluid dynamics tool created by Analytical Methods, Inc. This software uses the Euler flow model. Results from this software were used in the static stability evaluation and trim condition analysis. The trim conditions are the outcome of the optimisation process whose goal was to find the best front and rear flap deflection to achieve the best lift to drag (L/D) ratio.

The main outcome of this investigation is the proposal of strategy for the front and rear flap deflection which ensured the maximum L/D ratio and satisfied the trim condition. Moreover, the analysis of the mutual impact of the front and rear wings and the analysis of the control surface impact on the aerodynamic characteristic of the aircraft are presented.

In terms of aerodynamic computation, MGAERO software uses an inviscid flow model. However, this research is for the conceptual stage of the design and the MGAERO software grantee satisfied accurate respect to relatively low time of computations.

The ultimate goal is to build an aircraft in a tandem wing configuration and to conduct flying tests or wind tunnel tests. The presented result is one of the milestones to achieve this goal.

The aircraft in the tandem wing configuration is an aerodynamic-coupled configuration that needs detailed analysis to find the mutual interaction between the front and rear wings. Moreover, the mutual impact of the front and rear flaps is necessary too. Obtaining these results allowed this study to build the numerical model of the aircraft in the tandem wing configuration. It allows to find the best strategy of flap deflection, which allows to obtain the maximum L/D ratio and satisfy the trim condition.

AS befitting the occasion of its Silver Jubilee, the twenty‐fifth Paris International Air Show was indeed the most comprehensive yet staged. Nearly 700,000 people visited the Show during its eleven day run, and the International Flying Display on the final day drew an estimated 300,000. Close on 400 different types of aircraft were demonstrated in the air and on the ground, and a multitude of projects were illustrated on the stands of the Indoor Exhibition varying from Mach 3 supersonic transports to one‐man helicopters.

Perhaps the most difficult objection raised by skeptics of the real options approach concerns the apparent lack of market transactions that would verify that real options have actual value. Although there are no organized exchanges with publicly disclosed prices, there are nevertheless several mechanisms for buying and selling real options. Observing these could offer important advantages in the quest for enhancing the role of real options in financial decision making:•demonstrate that real options can indeed add value•in some cases even gain a sense of the amount of value added by real options•offer expert appraisers methods for improved estimation of the value of a business when real options are part of the organizational capital

The most frequently used method for buying or selling real options occurs when a product that includes real options is sold to customers (often at a premium above the price of a comparable product that does not include real options). Real options that are part of the organizational capital of a business are part of the package in an acquisition (or minority equity position). In this chapter we examine several cases of such transactions.

In his preface the author states that ‘this text was prepared to give in a concise and orderly manner the principles of vibration analysis that may be used to handle the usual problems that arise, and, at the same time, to lay the foundation for advanced work in this area’.

RADIATION DYNAMICS, a Monsanto subsidiary, has received an order for a Super‐X 3000B industrial radiographic linear accelerator from Rolls Royce Ltd (Advanced Projects Department, Corporate Engineering). This will be the second Super X accelerator supplied to Rolls Royce by Radiation Dynamics (the first one has been in operation since 1971). The two accelerators will be essential to the Rolls Royce aero‐engine development programme through to the end of the century.

To provide an overview of design activity undertaken within the CAPECON Project supported by European Commission and devoted to development of HALE UAV being proposed for long endurance flights.

Selected research methods devoted mainly to the improvement of dynamic stability of unmanned aerial vehicles have been described and their application into design optimisation are shown. The main goal of this research was to improve an economic effectiveness, safety and a modular arrangement of on‐board systems, especially with respect to sensors being easy replaceable for different missions.

The research and design process included an aerodynamic optimisation of swept wing, stability analysis, weight balance, some on‐board redundant systems, reliability and maintability analysis, safety improvement, cost and performance optimisation. A number of design iterations were performed to achieve the required aircraft performances and characteristics. This iteration number was relatively moderate (four cycles only) due to employing a modern software and the essential role of theoretical analysis performed parallel to the design and redesign process.

Analysis and design methodology is limited to surveillance, high altitude long endurance platforms, where the design objectives are high reliability, safety and low cost of production and operation.

A very useful source of design information and patterns to follow, especially for engineering students and engineers dealing with unmanned aviation.

This paper offers practical help for designers being involved with an unmanned platform to be well optimised for high altitude long endurance mission, giving a lot of practical information about many aspects of longitudinal and lateral stability of Blended Wing Body configuration, on‐board sensors and systems integrated with loading structure.