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The purpose of this paper is to investigate the feasibility of using rapid prototyping (RP) technologies (stereolithography (SLA), fused deposition modeling (FDM), and three‐dimensional printing (3DP)) for fabrication of the core of a composite sandwich structure.

Control cores of a flat geometry were fabricated from epoxy using SLA and from acrylonitrile butadiene styrene (ABS) plastic using FDM. Corrugated geometry cores were fabricated using SLA, FDM, and 3DP. Carbon‐epoxy composite sandwich structures were fabricated from all cores using a wet‐hand layup process with vacuum cure. The performance of each core was measured using a bend test to determine bending stiffness and failure load.

Based upon bending stiffness and failure load, composite sandwich structures utilizing epoxy cores fabricated via SLA outperformed composite sandwich structures utilizing plaster powder and ABS plastic cores. Composite sandwich structures with corrugated ABS plastic cores outperformed those with flat ABS plastic cores by a margin well beyond that predicted by theory in both bending stiffness and failure load.

The marked improvement in stiffness and failure load of the composite sandwich structures with corrugated ABS plastic cores over those with flat ABS cores is not explained by the theoretical improvement due to an increased area moment of inertia and increased surface area. Additional research in the failure mechanism is warranted.

The ability to easily create complex core geometries will allow for the ability to place enhanced structural features in the regions of high stress.

This paper demonstrates that cores fabricated via RP technology and containing enhanced structural features are suitable for carbon‐epoxy composite sandwich structures.

PLANNING and tooling for the smaller type of aircraft presents certain problems not encountered elsewhere. The main difficulty is that the confined space in which operators have to work when the aircraft is complete reduces the number of operators who can be employed at any time. Therefore, it is necessary to fit as much as possible of the systems and other equipment in the breakdown stage of the small aircraft, whereas, on the large aircraft more men can work inside the fuselage and this problem is not nearly so acute.

SIX years ago Sir W. G. Armstrong Whitworth Aircraft Ltd. began to take a serious interest in the design and development of tailless aircraft and today two types arc undergoing research flight testing.

The Origins of the Argosy and its Progressive Development from the AW.66 through to the Hawker Siddeley Series 222 Argosy including a Description of the Various Freight Handling Systems Devised for Use with the Aircraft and Concluding with a Review of Operational Experience. ALTHOUGH it was some years later that the name Argosy was given to the aircraft, the project began in 1955 when Sir W. G. Armstrong‐Whitworth Aircraft were invited to tender for a Medium Transport Aircraft to meet OR.323. This requirement called for an aircraft capable of carrying a payload of 10,000 lb. over a stage length of 1,500 nautical miles, with operation from 2,000 yds. runways at I.S.A.C.+30 deg. C. It had a freight hold over 42 ft. long, 9 ft. wide and 8 ft. high with a built‐in ramp/door at the rear for loading and supplies dropping. Inward opening paratroop doors were fitted on each side of the rear fuselage and there was an outward opening freight‐cum‐passenger door on the port side of the front fuselage. In this proposal the company considered various approaches for the tail configuration, a twin‐tail boom layout, a single tail boom layout and a twin‐tail boom layout with the booms projecting from the rear of the fuselage. This last layout was the one selected for submission as it gave more freedom for the loading ramp and a stiff tail support. Fig. 1 shows a model of the aircraft, powered with two Napier Eland engines and known as the AW.66.

This paper aims to study the effect of corrugated skins on the aerodynamic performance of the cambered NACA 0012 airfoils at different corrugations parameters, maximum cambers, Reynolds numbers and maximum camber locations.

In this work, numerical approach is concerned, and results are obtained based on the finite volume approach. To characterize the effect of corrugated skins, the NACA 0012-corrugated airfoil section is chosen as the base airfoil, and different cambered corrugated airfoil sections are obtained by inclusion the camber to the base airfoil. In this research, the corrugation shape is a sinusoidal wave and corrugated skins are in the aft 30 per cent of airfoil chord. To investigate the effect of corrugations on the cambered sections, the drag coefficient and averaged lift curve slope for the corrugated airfoils are compared to those of the corresponding smooth sections.

Results indicate that the effect of increase in the maximum camber and also Reynolds number on the relative zero-incidence drag coefficient is of little importance at low corrugation amplitudes, whereas at high corrugation, amplitude results in different behaviors. It is found that as the maximum camber increases, the deterioration in the relative curve slope introduced by corrugated skins is reduced, and reduction in this deterioration is significant for high corrugation amplitudes airfoils. It is shown that an increase in the maximum camber location has nearly no effect on the relative zero-incidence drag coefficient and also relative lift curve slope.

The outcome of the present research provides the clues for better understanding of the effect of different corrugations parameters on the aerodynamic performance of the unmanned air vehicles to have as high aerodynamic performance as possible in different mission profiles of such vehicles.

THE flight trials programme of the Skyvan is based on achieving a Group C (temperate category) Certificate of Airworthiness, within a period of six months after the production aircraft's first flight. To achieve this goal full use has been made of the prototype aircraft both in its original piston engine form and in the developed form with Astazou turboprop engines fitted. The original prototype Skyvan (the version fitted with Continental piston engines and designated the Mk. I) flew during the period January to May 1963. It was then modified by fitting Astazou turboprop engines, re‐designated the Skyvan IA and flew again in October 1963; it is still flying and continuing with development trials associated with the clearance of the production aircraft. The production aircraft to be known as the Skyvan Mk. II will be fitted with the more powerful Astazou X engines and will operate at a higher all‐up weight than is possible on the Skyvan I. It is scheduled to fly in the last quarter of 1965 and certification is expected in early 1966.

THE Short SD3‐30 is a wide‐bodied Feederliner optimised for commuter and regional air services. The aircraft has been designed to accommodate up to 30 passengers with baggage plus 3 crew or 7500 lb of freight (3400 kg) and thus conforms with the new Part 298 Regulation of the United States Civil Aeronautics Board. Its operating economics are optimum over sectors of 100 to 300 nautical miles (185 km to 555 km). A large forward loading door capable of accepting ‘D’ size containers is available which facilitates use of the aircraft in mixed passenger/freight configurations. The aircraft will be fully certificated to US Federal Aviation Regulations Part 25 and to British Civil Airworthiness Requirements Group A category.

An Account of the Design Philosophy Pursued for the Principal Load‐Carrying Structures and the Materials Employed. THE attention commonly devoted to the structural problems of large aircraft might lead one to suppose that small aircraft offer little scope for constructive thought. However, a brief consideration of size effects and the factors behind the structural philosophy adopted on the Skyvan show this to be far from true.

Brief Details of Materials, Components and Equipment Produced by a Number of Companies in Support of the Belfast Programme Including Details of the Arrangements for Power Plant Maintenance and Overhaul. AS has already been stressed in the earlier article on Structural Design of the Turbo‐Skyvan, Redux adhesive, made by Bonded Structures Ltd., is used extensively in the construction of the aircraft. Both the fuselage and the wing skins are made up by bonding a corrugated inner skin to an outer skin—this method producing an extremely strong and light structure.

The current research conducts a comprehensive review on FishBAC (fishbone active camber morphing wing surfaces) for researchers and scientists and sheds light on challenges and opportunities of FishBAC development.

This is a review article and this study reviews previous research on FishBAC.

The current FishBAC applications could be upgraded into more efficient designs in materials, design and mechanisms with more perspectives involved. Then, this promising branch of morphing surface design could be integrated with rotor blades, unmanned aerial vehicle wings, general aviation aircraft surfaces and so on.

This is a review article.

The contributions of the study are summarized as follows: to provide an overview of FishBAC research; to compare various approaches and trends in FishBAC designs; to address the research gap in the roadmap for FishBAC design; and to discuss the challenges and opportunities of FishBAC development.

To the best of the authors’ knowledge, this is the first review on a promising morphing method and an alternative for conventional flaps and ailerons.