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THE Farnborough 1966 Show was at first glance much the same mixture as before, but the second glance was the more revealing. The participation in the flying display of European aircraft by no means swamped the air, even if the Italian verve took the acrobatic honours, but the theme of collaboration with other countries was to be found on practically every stand inside the exhibition tent. It was obvious that the smaller firms not directly involved in production agreements with other nations were very export conscious. The pacemaker of all this collaboration was of course the Concorde, only to be seen in model form, but rapidly taking shape at Toulouse and Filton, and many of the equipment manufacturers had Concorde hardware on display. Beagle announced the Pup, Britten‐Norman produced the production Islander, and Handley Page showed the Jetstream mock‐up. After many years of neglect, the industry is now taking an interest in the general aviation market. The P.1127 (R.A.F.) made its first appearance. The paradox of the P.1127 is that it is almost a part of Farnborough history, yet there is no other V/S.T.O.L. aircraft in the world that has but a fraction of the operating experience it has gained. Farnborough this year gave the impression of being more a serious trade show, and less a public spectacle. Sir Richard Smeeton, Director of the Society of British Aerospace Companies, reported that the exhibiting firms had received more serious business enquiries this year than ever before, and he forecast that 1968 would be a vintage year, which would see the appearance of the HS.801, the Concorde and Jaguar in the Farnborough skies. It is not possible to cover every exhibit shown at the Farnborough Show, but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

The purpose of this paper is to study how cryogenic CO₂ cooling during the welding process affects corrosion behaviour of friction stir welding (FSW) AA7010‐T7651.

Friction stir welded AA7010‐T7651 was produced with a rotation speed of 288 rpm and a travel speed of 58 mm/min. The liquid CO₂ was sprayed onto the weld centre line immediately after the toolpiece. The microstructures of welds in different regions were observed using Field Emission Gun Scanning Electron Microscope (FEG‐SEM). The effect on the corrosion susceptibility was investigated using a gel visualisation test and potentiodynamic polarisation measurements using a micro‐electrochemical technique.

The main corrosion region for both FSWs AA7010‐T7651 produced with and without cryogenic CO₂ cooling is in the HAZ region, which exhibited intergranular attack. Cryogenic cooling does not show any influence on anodic reactivity of the weld region (both nugget and HAZ) compared to uncooled weld metal. However, the width of the reactive HAZ is reduced after cooling, as compared to the uncooled weld. The cooled welds show higher cathodic reactivity in the nugget region than does the nugget region of uncooled welds.

There has been no previous work to investigate the effect of cryogenic CO₂ cooling on the corrosion behaviour of FSW AA7010‐T7651. The paper relates the microstructures of both uncooled and cooled welds to their anodic and cathodic reactivities using a micro‐electrochemical technique.

The paper aims to elaborate the method and algorithm of analysis of induction motor working in cryogenic temperature.

This paper presents the design and investigation of performance characteristics of three‐phase high voltage squirrel‐cage submerged motor. The motor is intended to work at cryogenic temperature −161°C in liquefied natural gas (LNG). The time‐stepping finite element method of transients analysis in induction motor working in cryogenic temperature has been presented. The nonlinearity of the magnetic circuit, the movement of the rotor and skewed slots have been taken into account.

The study finds that presented method and elaborated software are used to determine the steady state and dynamic performance of the high voltage squirrel‐cage submerged motor. The results of simulations and measurements of constructed model motor have been presented.

The problem has been considered as the 2D one. In order to take into account the skewed slots of the rotor the multi‐slice finite element method has been used.

Investigation presented in the paper has been performed in order to study the influence of the temperature on motor characteristics and to verify design calculations. No‐load current, starting torque and short‐circuit current during short‐circuit test, obtained on the basis of measurements and received from calculations, are in good concordance.

The paper proposes a method to determine the steady state and dynamic performance of the high voltage squirrel‐cage submerged motor working in cryogenic temperature.

KEK Ltd., Hurdsfield Industrial Estate, Macclesfield, Cheshire SK10 2ND, announce an extension to their cryogenic grinding facility with the installation of a 2000 litre nitrogen tank (approximately 3 times the size of the previous facility).

The purpose of this paper is to develop a new bio‐plotter using a rapid freeze prototyping (RFP) technique and to investigate its potential applications in fabricating tissue scaffolds.

The development of cryogenic bio‐plotters including design steps of hardware as well as software is addressed. Effects of structural parameters and process parameters on the properties of tissue scaffolds are demonstrated through simulation and experimental results.

The paper finds that the RFP method is suitable to fabricate macro‐ and micro‐porous scaffolds, especially for temperature‐sensitive polymers. In addition, through simulation and experiment results, it also shows that macro‐ and micro‐porous properties could be manipulated by structural parameters and process parameters, respectively.

This paper shows that the chamber temperature is an important process parameter that can provide the means to control the micro‐porous structure of the scaffold. However, if the temperature is set too high, the fiber is frozen so rapidly that it cannot be fused with other fibers of the previous layer. On the other hand, if the temperature is too low, the fiber is not solidified fast enough. So, the chamber temperature, together with extruding pressure and nozzle velocity, must be optimized, which will be further investigated in future work.

The RFP technique is successfully proposed to construct 3D tissue scaffolds. In addition, a new cryogenic bio‐plotter is designed and developed, in which general algorithms of rapid prototyping method are presented and implemented, facilitating the fabrication of tissue scaffolds with various cross‐hatching patterns in a RFP process.

Two new products of considerable significance are to be unveiled at Paris by Elliott‐Automation Ltd., in addition to a full range of their other products. A display on the B.o.T. stand will highlight their achievements in the field of flight control for automatic landing (AIRCRAFT ENGINEERING, September 1966, p. 49). The Concorde autopilot will be featured on their own stand, with the latest autopilot control panel for the pre‐production aircraft which embodies nightly sophisticated push‐button switching on show. Another exhibit will be the Starling state 5 attitude control system for the Skylark sounding rocket.

THE Twenty‐fourth S.B.A.C. Flying Display and Exhibition to be held at Farnborough during the week Monday,September 7, to Sunday, September 13, promises to be the most interesting ever held. This is in part due to the decision taken in 1962 not to hold an S.B.A.C. Show in the summer of 1963, and partly the result of the effort now being concentrated upon the Concord supersonic airliner project, the TSR‐2 supersonic strike and reconnaissance bomber, the Hawker Siddeley P. 1154 V/STOL fighter, two new research aircraft and a whole range of new transport aircraft. Apart from the models and displays which will be mounted by the major airframe and engine manufacturers demonstrating their own involvement with these projects and programmes, the stands of the Associate Members of the Society of British Aerospace Companies will abound with examples of materials, techniques and equipment which these companies are producing in support of the latest programmes—notably TSR.2 and Concord.