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The purpose of this paper is to give a brief introduction of helical spring locked washer along with extensive literatures survey on role of helical spring locked washer in bolted joint analysis. It is very small component of bolted joint assembly, but it play vital role in holding the assembly components together. Helical shape of it produces spring effect in the assembly which is used for keeping the assembly in tension and that is lock the assembly under dynamic loading due to vibrations to avoid the accident.

The critical literatures survey identifies role of helical spring locked washer in different areas such as design optimization, mechanism of loosening-resistant components, bolted joint analysis, finite element-based modeling, analysis and simulation. The related literatures show contribution of helical spring washers in evaluation of anti-loosening performance of assemblies as compare to other types of washers.

It proposed that design optimization of helical spring locked washer is needed as it improves the performance in the form of load-deflection characteristics, load bearing capacity and provides the best locking force for optimize functionality.

The originality or value of this paper is to finding research gaps in literatures by dividing literatures into seven different research areas and concentrating the only on role of helical spring locked washer in bolted joint analysis.

Racal Avionics announce its latest navigation computer, the ‘Keyboard RNS252’, designed to meet the navigation requirements of both helicopters and fixed wing aircraft for the future.

BMW 801A/1 The engine is a radial, air‐cooled, fourteen‐cylindcr, double‐bank motor of 42 litres capacity, 6–5/1 compression ratio and 156 mm. bore and stroke.

In the scries of British Standards which is being prepared covering electroplated coatings, the British Standards Institution has just published this document dealing specifically with protective coatings on electroplated articles. It docs not cover coatings on sheet, strip or wire.

THE Gipsy engine is manufactured by the de Havilland Aircraft Co., Ltd., Stag Lane Aerodrome, Edgware, Middle‐sex, and is the result of many years' experience of the designers in the demands of civil aviation for an engine giving a high standard of efficiency and reliability, combined with exceptional economy, easy interchangeability and accessibility of parts for both maintenance and repair.

Civil Specification Memorandum No. 22 1. This Memorandum cancels the following Civil Specification Memoranda:—

A LONG chain of processes is involved in the gradual building up and combining of all the innumerable parts that go to make the complete aeroplane. It starts with the gathering together of the individual parts to form sub‐components, which are then joined in sub‐assemblies to be brought together to form main components, which are at last collected at the final‐assembly line to be merged into one whole—the aeroplane. Delay at any one of these intermediate stages will cause a hold‐up all the way back, but most serious of all is a “bottle‐neck” at the final‐assembly line. It is of the greatest importance that the time to be occupied at each of the assembly stages should be carefully planned, estimated and checked, but however smooth a flow may be provided the whole effort will be wasted if main component assemblies are to pile up waiting for space in the anal assembly shop. The more reliance that is placed, in the modern manner, on sub‐contractors and “outside” firms for production of parts, sub‐components, sub‐assemblies and, in some astances, main components, the more serious the consequences of his final hold‐up. It is a frequent cause of bewilderment to the mind to hear of men employed at the works of sub‐contractors ing “stood off” at a time when clearly the maximum possible output of completed machines is desirable. This is, of course, due ry frequently to congestion at some later stage in the process of sembling, and the later the stage at which this occurs the more widespread will be the resulting confusion and delay. If there is a stoppage in the flow along the final‐assembly line it may be that a considerable number of firms are affected and forced temporarily to stop production until the stoppage is cleared.

THE rules for the 1935 Deutsch de la Meurthe Cup Race remained almost identical with those of 1933 and 1934. Briefly, the contest was open to all types of land “aerodynes”; the only limitation being that the total capacity of the engine (or engines) remained under 8 litres (488·20 cu. in.). In other directions, designers were left with an absolutely free hand—the usual Certificate of Airworthiness even being dispensed with. To avoid the participation of machines of doubtful characteristics, each competitor had to qualify between April 2 and May 2 by passing successfully the following tests: a flight of 500 km. (311 miles) in a closed circuit at a speed exceeding 300 k.p.h. (186·5 m.p.h.)—against 250 k.p.h. (155·5 m.p.h.) last year. In addition, take‐off and landing had to be performed in less than 500 metres (1,640 ft.) over a “screen” 1 metre (3·28 ft.) high—against 550 metres (1,801 ft.) last year. Actually, the “screen” took the form of two parallel ropes set at the required height and separated by an interval of 50 metres (164 ft.), so as to ensure correct execution of the test. The wind velocity had to be under 6 metres per second (19·7 f.p.s.) during the take‐off and landing tests.

AIRCRAFT INSTRUMENTS THE instruments used in aircraft are of a highly specialised nature. They have to stand up to very severe conditions in service. They are subjected to continual vibration during the whole time the engine is running, and to severe shocks in landing and when taxying on the ground. They are expected to function no matter what the position of the aircraft, and to stand reduced air pressures due to altitude, as well as a range of temperature altogether unusual in the case of instruments used for any other purpose. It is well to emphasise these peculiar conditions as they are not always fully appreciated.

Robots are not the only answer to assembly of parts in batch quantities. A so called dedicated machine can assemble a variety of parts by grouping them into families. Brian Rooks recently saw such a machine at the Trent Works, of Vaughan Associates and now presents his report.