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This study aims to develop a new correlation method for prediction of in-flight wings deflections by integration of the experimental ground tests with computational fluid dynamics (CFD) analysis.

The ground test results are implemented in the curve fitting process to determine deflections at 66 specific points (SPs) on the front and rear wing torque box. By using the obtained deflections and the corresponding applied loads, an experimental deflection equation (EDE) for each point is established through the Castigliano’s theorem. The CFD aerodynamic loads of typical aircraft, which have been obtained earlier by the authors, are once again used in the current research. The total applied loads to each part are achieved via summation of inertia and aerodynamic loads. The obtained loads are transformed to the equivalent concentrated loads at the SPs. By substituting the concentrated load values in the EDEs, the SPs deflections are achieved for mentioned flight conditions. The resulted deflections and the corresponding input flight parameters, i.e. M and α, are incorporated into a linear regression method for development of the appropriate in-flight deflection equations (IFDEs). The validity of IFDEs is approved by comparing IFDEs’ deflections with the corresponding ones calculated through EDEs for different flight conditions.

As an alternative approach to the fairly expensive flight tests, the IFDEs can be used to predict the in-flight wing deflections with comparable degree of accuracy.

Prediction of actual wing deflections distributions without flight tests execution at any given flight condition.

In modeling an aircraft wing, structural idealizations are often employed in hand calculations to simplify the structural analysis. In real applications of structural design, analysis and optimization, finite element methods are used because of the complexity of the geometry, combined and complex loading conditions. The purpose of this paper is to give a comprehensive study on the effect of using different structural idealizations on the design, analysis and optimization of thin walled semi-monocoque wing structures in the preliminary design phase.

In the design part of the paper, wing structures are designed by employing two different structural idealizations that are typically used in the preliminary design phase. In the structural analysis part, finite element analysis of one of the designed wing configurations is performed using six different one and two dimensional finite element pairs which are typically used to model the sub-elements of semi-monocoque wing structures. Finally in the optimization part, wing structure is optimized for minimum weight by using finite element models which have the same six different finite element pairs used in the analysis phase.

Based on the results presented in the paper, it is concluded that with the simplified methods, preliminary sizing of the wing configurations can be performed with enough confidence as long as the simplified method based designs are also optimized iteratively, which is what is practiced in the design phase of this study.

This research aims at investigating the effect of using different one and two dimensional element pairs on the final analyzed and optimized configurations of the wing structure, and conclusions are inferred with regard to the sensitivity of the optimized wing configurations with respect to the choice of different element types in the finite element model.

ALTHOUGH the first certification or the Jetstream is to be to B.C.A.R. Section K and F.A.R. Part 23, it has always been intended that full airline standards will be maintained and ultimately certification to Section D, and Part 25 will be obtained. From the point of view of static strength these standards differ little and will have a minor effect only on the structural design. The spirit of the full airline requirements, however, is aimed at long life and fail safe philosophies, and this has been foremost in the thought behind Jetstream's structure. The design crack‐ free life is 40,000 flights (30,000 hours) with the additional aim of a fail safe primary structure. The long crack‐free life will be obtained by restricting the working and fluctuating stresses to values decided for each component by its own spectrum of load cycles. Fail safe primary structure is achieved by the duplication of members, alternative load paths, ‘catchers’, or by effective crack stoppers.

THE OBJECTIVES of this article are twofold, firstly to argue the case for variable configuration aircraft, i.e. aircraft whose planform can be adjusted in flight to give optimum performance in differing roles; and secondly, to put forward proposals for a wing suspension designed to overcome the handicaps inherent in the method so far employed in mounting the wings of variable configuration aircraft.

To provide an effective design methodology focused on loading structure of unmanned aerial vehicles with a special emphasis on MALE class platform.

Selected design methods and numerical calculations used during the development of two different class (MALE PW‐103 and HALE PW‐114) unmanned aerial vehicles have been described and discussed. The initial loading structure was set‐up coming from a steady state level flight condition.

Aeroelastic analysis showed that the wing torsional rigidity is not sufficient. To increase the critical flutter speed the wing sandwich skin has been reinforced adding extra layers of carbon fibres. This procedure is iterative by nature, because adding the new layers changes the weight and stiffness of aircraft and the critical flutter speed has to be computed again.

Analysis and design methodology is limited to surveillance and monitoring platforms, where the design objectives are long endurance, high reliability and cost effectiveness of the platform.

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 planning an unmanned platform to be well adjusted to the assumed mission, giving a lot of practical information about attachments and fittings, on‐board systems integrated with loading structure and integration of composites with metal parts in modern flying platforms.

THE aviation industry is undertaking development of the most comprehensive support programme in its history—the support programme for the supersonic transport. Boeing's SST, for example, will cost over $35 million and will cruise at 30 miles a minute at altitudes of 60,000 ft. or more. The aircraft is being designed to achieve a dispatch reliability of 99 per cent, a design life of 50,000 hours, and a utilization potential of 3,000 hours per year to meet fully its economic objectives. The kind of support programme the SST will require can only be found by examining some of the aspects of this new aeroplane.

SINCE the public debut of its progenitor, the Hawker P 1127 at the 1962 Farnborough Air Show its descendants, the Kestrel and the Harrier have continued to astonish and delight the crowds, both hardened professionals and the general public at Air Shows throughout the free world.

This paper aims to provide a shimming method based on scanned data and finite element analysis (FEA) for a wing box assembly involving non-uniform gaps. The effort of the present work is to deal with gap compensation problem using hybrid shims composed of solid and liquid forms.

First, the assembly gaps of the mating components are calculated based on the scanned surfaces. The local gap region is extracted by the seed point and region growth algorithm from the scattered point cloud. Second, with the constraints of hole margin, gap space and shim specification, the optional shimming schemes are designed by the exhaustive searching method. Finally, the three-dimensional model of the real component is reconstructed based on the reverse engineering techniques, such as section lines and sweeping. Using FEA software ABAQUS, the stress distribution and damage status of the joints under tensile load are obtained for optimal scheme selection.

With the scanned mating surfaces, the non-uniform gaps are digitally evaluated with accurate measurement and good visualization. By filling the hybrid shims in the assembly gaps, the joint structures possess similar load capacity but stronger initial stiffness compared to the custom-shimmed structures.

This method has been tested with the interface data of a wing tip, and the results have shown good efficiency and automation of the shimming process.

The proposed method can decrease the manufacturing cost of shims, shorten the shimming process cycle and improve the assembly efficiency.

The purpose of this paper is to present the process of design and prototyping of a two-seat, electric-powered, self-launching motorglider AOS-71 closely connected with the teaching process conducted by the academic staff of Warsaw University of Technology (WUT) within a unique educational ULS – Ultra Light Sailplanes programme.

The selected design methods and tools used during the development of the motorglider have been described. The computer aided design/computer aided manufacturing modules of the Siemens NX software were used to work on the structural design, tools and technical documentation. The core of the ULS educational programme is to educate aerospace engineering students by providing an opportunity for them to participate in each phase of the aircraft life cycle – from conceptual drawings through structural design and prototyping to manufacturing, testing and maintenance.

The main innovations of the AOS-71 design are: retractable ecological electric propulsion, spacious cockpit where seats are located side by side and the all-composite airframe made of 90 per cent advanced carbon epoxy composites.

The electric motorglider can be used as a multifunctional flying laboratory for flight research and student education.

The AOS-71 project and its continuation are a valuable example of involving aerospace students in each phase of the aircraft life cycle. It also contributes to the research in the field of using innovative electrical propulsion systems in aircraft designs.

Brief Details of Some of the Components and Equipment Produced by a Number of Companies in Support of the Super VC10 Programme. THE preceding articles have dealt with the raison d'être of the Super VC10, interior engineering, technical details of the combined passenger/freight version, principal differences between the Standard and Super VC10s, development of Economy class seating for B.O.A.C.'s VC10s and aircraft systems. It is the object of this final article to provide some additional information regarding Super VC10 equipment and systems in the form of the contribution made by specific firms to the Super VC10 programme.