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When a thick structure is, on the contrary, subjected to moisture absorption, a fairly long time may be needed to reach full saturation. It is, therefore, important to understand and predict the areas of complex composite structures that are more prone to saturation. The material knock-down factors (proportional to the moisture content) may be applied only to these zones, in order to obtain a less pessimistic structural response prediction. The purpose of this paper is to investigate an FE diffusion model that was used to validate the absorption testing results of thick carbon epoxy laminates.

The experimental results were validated by using a diffusion model in Abaqus FE code.

The absorption results of three 15 mm thick carbon epoxy laminates are presented and reproduced via a mass diffusion model. The laminates were conditioned at 70°C and 85 per cent relative humidity in a moisture chamber. Areas more prone to saturation have been predicted by the FE model and the moisture content in the non-saturated areas has been calculated.

The practical implications of the absorption model are discussed on an example of an aero-engine fan blade-like structure.

Validation of thick panels’ absorption data is an important point of novelty of this paper, given the lack of experimental and modelling validation in the open literature.

Dowty Rotol and GE Aircraft Engines signed an agreement to collaborate in a joint programme covering the design, development, and manufacture of composite fan blades for the GE36 Unducted Fan (UDF) engine.

THE Rolls‐Royce RB.211 turbofan engine in various ratings is on firm offer for the proposed large three‐engined transport aircraft such as the McDonnell Douglas DC‐10 and the Lockheed 1011 now being designed in the United States. First certificated engines will be available in December 1970, at a basic price of around $½ million varying according to the rating chosen. The engine is also offered for 200‐seat twin engine transports. A typical specification is as follows:

A transient dynamic finite element procedure is presented for failure analysis of centrally‐impacted laminated composite pretwisted rotating plates. A nine‐noded, three‐dimensional degenerated composite shell element is developed and used for the present finite element formulation. Effects of transverse shear deformation and rotary inertia are included. The strength‐of‐material type failure criteria are adopted and the “total ply discount” approach is used as the stiffness reduction model. The dynamic equilibrium equation is derived by applying Lagrange’s equation of motion and the investigation is carried out for moderate rotational speeds for which the Coriolis effect is negligible. The modified Hertzian contact law is utilized to compute the contact force between the impactor and the laminated plate. Impact failure analyses of pretwisted rotating plates are performed to investigate the effects of angle of twist, rotational speed and laminate configuration.

Fan blades made of layers of graphite/epoxy coated with titanium reportedly enable the GE90 gas turbine engine from General Electric Aircraft Engines, Cincinnati, Ohio, to deliver more power while using less fuel and reducing pollution. The GE90 will power the new Boeing 777 widebody aircraft.

This paper seeks to describe an innovative new technology for digitizing the shapes of 3D objects quickly and accurately, which uses accordion fringe interferometry (AFI).

Laser beams cast fringe patterns on objects, a digital camera captures images and software constructs point clouds of data. A software package then analyzes the point cloud to extract information such as dimensions or variations in shape for subsequent operations.

The AFI approach has already been applied to a number of applications such as: inspection of jet engine airfoils, repair of composite structures and inspection of very delicate objects.

Point cloud digital shape scanning will find an ever increasing number of applications which will benefit from this fast, accurate and non‐contact three‐dimensional digitizing technology.

Users now have a totally new means for capturing dense, three‐dimensional data.

The first four British Aerospace Hawk Mk65 advanced jet trainers delivered to the Royal Saudi Air Force arrived in Saudi Arabia on October 13 after a 3,000nm ferry flight from British Aerospace's Dunsfold aerodrome in Surrey. The aircraft made only one overnight refuelling stop in Athens on their way to Saudi Arabia. They will be used by the Royal Saudi Air Force for advanced aircrew training as part of a syllabus which includes basic training on the Pilatus PC‐9 turboprop trainer.

Jet engine maker Pratt & Whitney has a record number of nine engine flight tests under way, for powerplant models ranging in trust from 26,500lbs to more than 84,000lbs.

Reports from AMK Berlin indicate that over 280,000 visitors attended ILA92 Airshow in Berlin. The first airshow to take place at Berlin‐Schönefeld Airport for the last 64 years.